From a1af3c27d4b15fa1de5f829f8f9e4ecb20c2eff6 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 12:37:32 +0100
Subject: [PATCH 01/13] refactor: extract almost.Equal() to new package

To avoid a circular reference between promql and promqltest.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/engine_test.go |  3 ++-
 promql/quantile.go    |  3 ++-
 promql/test.go        | 33 ++++-----------------------------
 util/almost/almost.go | 41 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 49 insertions(+), 31 deletions(-)
 create mode 100644 util/almost/almost.go

diff --git a/promql/engine_test.go b/promql/engine_test.go
index 0202c15ae..36f36807a 100644
--- a/promql/engine_test.go
+++ b/promql/engine_test.go
@@ -35,6 +35,7 @@ import (
 	"github.com/prometheus/prometheus/promql/parser/posrange"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/tsdbutil"
+	"github.com/prometheus/prometheus/util/almost"
 	"github.com/prometheus/prometheus/util/annotations"
 	"github.com/prometheus/prometheus/util/stats"
 	"github.com/prometheus/prometheus/util/teststorage"
@@ -3873,7 +3874,7 @@ func TestNativeHistogram_HistogramQuantile(t *testing.T) {
 
 						require.Len(t, vector, 1)
 						require.Nil(t, vector[0].H)
-						require.True(t, almostEqual(sc.value, vector[0].F, defaultEpsilon))
+						require.True(t, almost.Equal(sc.value, vector[0].F, defaultEpsilon))
 					})
 				}
 				idx++
diff --git a/promql/quantile.go b/promql/quantile.go
index 6a225afb1..d4bc9ee6e 100644
--- a/promql/quantile.go
+++ b/promql/quantile.go
@@ -20,6 +20,7 @@ import (
 
 	"github.com/prometheus/prometheus/model/histogram"
 	"github.com/prometheus/prometheus/model/labels"
+	"github.com/prometheus/prometheus/util/almost"
 )
 
 // smallDeltaTolerance is the threshold for relative deltas between classic
@@ -397,7 +398,7 @@ func ensureMonotonicAndIgnoreSmallDeltas(buckets buckets, tolerance float64) (bo
 			// No correction needed if the counts are identical between buckets.
 			continue
 		}
-		if almostEqual(prev, curr, tolerance) {
+		if almost.Equal(prev, curr, tolerance) {
 			// Silently correct numerically insignificant differences from floating
 			// point precision errors, regardless of direction.
 			// Do not update the 'prev' value as we are ignoring the difference.
diff --git a/promql/test.go b/promql/test.go
index 1cdfe8d31..b982c33c3 100644
--- a/promql/test.go
+++ b/promql/test.go
@@ -19,7 +19,6 @@ import (
 	"errors"
 	"fmt"
 	"io/fs"
-	"math"
 	"strconv"
 	"strings"
 	"testing"
@@ -36,13 +35,12 @@ import (
 	"github.com/prometheus/prometheus/promql/parser"
 	"github.com/prometheus/prometheus/promql/parser/posrange"
 	"github.com/prometheus/prometheus/storage"
+	"github.com/prometheus/prometheus/util/almost"
 	"github.com/prometheus/prometheus/util/teststorage"
 	"github.com/prometheus/prometheus/util/testutil"
 )
 
 var (
-	minNormal = math.Float64frombits(0x0010000000000000) // The smallest positive normal value of type float64.
-
 	patSpace       = regexp.MustCompile("[\t ]+")
 	patLoad        = regexp.MustCompile(`^load\s+(.+?)$`)
 	patEvalInstant = regexp.MustCompile(`^eval(?:_(fail|ordered))?\s+instant\s+(?:at\s+(.+?))?\s+(.+)$`)
@@ -551,7 +549,7 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 					return fmt.Errorf("expected float value at index %v for %s to have timestamp %v, but it had timestamp %v (result has %s)", i, ev.metrics[hash], expected.T, actual.T, formatSeriesResult(s))
 				}
 
-				if !almostEqual(actual.F, expected.F, defaultEpsilon) {
+				if !almost.Equal(actual.F, expected.F, defaultEpsilon) {
 					return fmt.Errorf("expected float value at index %v (t=%v) for %s to be %v, but got %v (result has %s)", i, actual.T, ev.metrics[hash], expected.F, actual.F, formatSeriesResult(s))
 				}
 			}
@@ -601,7 +599,7 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 			if expH != nil && !expH.Compact(0).Equals(v.H) {
 				return fmt.Errorf("expected %v for %s but got %s", HistogramTestExpression(expH), v.Metric, HistogramTestExpression(v.H))
 			}
-			if !almostEqual(exp0.Value, v.F, defaultEpsilon) {
+			if !almost.Equal(exp0.Value, v.F, defaultEpsilon) {
 				return fmt.Errorf("expected %v for %s but got %v", exp0.Value, v.Metric, v.F)
 			}
 
@@ -621,7 +619,7 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 		if exp0.Histogram != nil {
 			return fmt.Errorf("expected Histogram %v but got scalar %s", exp0.Histogram.TestExpression(), val.String())
 		}
-		if !almostEqual(exp0.Value, val.V, defaultEpsilon) {
+		if !almost.Equal(exp0.Value, val.V, defaultEpsilon) {
 			return fmt.Errorf("expected Scalar %v but got %v", val.V, exp0.Value)
 		}
 
@@ -894,29 +892,6 @@ func (t *test) clear() {
 	t.context, t.cancelCtx = context.WithCancel(context.Background())
 }
 
-// almostEqual returns true if a and b differ by less than their sum
-// multiplied by epsilon.
-func almostEqual(a, b, epsilon float64) bool {
-	// NaN has no equality but for testing we still want to know whether both values
-	// are NaN.
-	if math.IsNaN(a) && math.IsNaN(b) {
-		return true
-	}
-
-	// Cf. http://floating-point-gui.de/errors/comparison/
-	if a == b {
-		return true
-	}
-
-	absSum := math.Abs(a) + math.Abs(b)
-	diff := math.Abs(a - b)
-
-	if a == 0 || b == 0 || absSum < minNormal {
-		return diff < epsilon*minNormal
-	}
-	return diff/math.Min(absSum, math.MaxFloat64) < epsilon
-}
-
 func parseNumber(s string) (float64, error) {
 	n, err := strconv.ParseInt(s, 0, 64)
 	f := float64(n)
diff --git a/util/almost/almost.go b/util/almost/almost.go
new file mode 100644
index 000000000..34f1290a5
--- /dev/null
+++ b/util/almost/almost.go
@@ -0,0 +1,41 @@
+// Copyright 2024 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package almost
+
+import "math"
+
+var minNormal = math.Float64frombits(0x0010000000000000) // The smallest positive normal value of type float64.
+
+// Equal returns true if a and b differ by less than their sum
+// multiplied by epsilon.
+func Equal(a, b, epsilon float64) bool {
+	// NaN has no equality but for testing we still want to know whether both values
+	// are NaN.
+	if math.IsNaN(a) && math.IsNaN(b) {
+		return true
+	}
+
+	// Cf. http://floating-point-gui.de/errors/comparison/
+	if a == b {
+		return true
+	}
+
+	absSum := math.Abs(a) + math.Abs(b)
+	diff := math.Abs(a - b)
+
+	if a == 0 || b == 0 || absSum < minNormal {
+		return diff < epsilon*minNormal
+	}
+	return diff/math.Min(absSum, math.MaxFloat64) < epsilon
+}

From 2b0c87b1b6ee494c75448f23e6465c8cf20acda0 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Wed, 8 May 2024 11:47:03 +0100
Subject: [PATCH 02/13] test: turn TestKahanSum into scripted test

This saves having a function solely to call kahanSumInc.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/functions.go            | 9 ---------
 promql/functions_test.go       | 7 -------
 promql/testdata/functions.test | 8 ++++++++
 3 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/promql/functions.go b/promql/functions.go
index 2e15a1467..9b3be2287 100644
--- a/promql/functions.go
+++ b/promql/functions.go
@@ -948,15 +948,6 @@ func funcTimestamp(vals []parser.Value, args parser.Expressions, enh *EvalNodeHe
 	return enh.Out, nil
 }
 
-func kahanSum(samples []float64) float64 {
-	var sum, c float64
-
-	for _, v := range samples {
-		sum, c = kahanSumInc(v, sum, c)
-	}
-	return sum + c
-}
-
 func kahanSumInc(inc, sum, c float64) (newSum, newC float64) {
 	t := sum + inc
 	// Using Neumaier improvement, swap if next term larger than sum.
diff --git a/promql/functions_test.go b/promql/functions_test.go
index 6d5c3784e..08e4900f5 100644
--- a/promql/functions_test.go
+++ b/promql/functions_test.go
@@ -15,7 +15,6 @@ package promql
 
 import (
 	"context"
-	"math"
 	"testing"
 	"time"
 
@@ -80,9 +79,3 @@ func TestFunctionList(t *testing.T) {
 		require.True(t, ok, "function %s exists in parser package, but not in promql package", i)
 	}
 }
-
-func TestKahanSum(t *testing.T) {
-	vals := []float64{1.0, math.Pow(10, 100), 1.0, -1 * math.Pow(10, 100)}
-	expected := 2.0
-	require.Equal(t, expected, kahanSum(vals))
-}
diff --git a/promql/testdata/functions.test b/promql/testdata/functions.test
index e01c75a7f..2c198374a 100644
--- a/promql/testdata/functions.test
+++ b/promql/testdata/functions.test
@@ -764,6 +764,14 @@ eval instant at 1m avg_over_time(metric10[1m])
 eval instant at 1m sum_over_time(metric10[1m])/count_over_time(metric10[1m])
   {} 0
 
+# Test if very big intermediate values cause loss of detail.
+clear
+load 10s
+  metric 1 1e100 1 -1e100
+
+eval instant at 1m sum_over_time(metric[1m])
+  {} 2
+
 # Tests for stddev_over_time and stdvar_over_time.
 clear
 load 10s

From a6e427660aa7e6b360049f8bf6990c3bdb80a9aa Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Sat, 4 May 2024 14:22:28 +0100
Subject: [PATCH 03/13] test: check for @-modifier without using engine
 internals

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/test.go | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/promql/test.go b/promql/test.go
index b982c33c3..2cfcfce6f 100644
--- a/promql/test.go
+++ b/promql/test.go
@@ -676,8 +676,7 @@ func atModifierTestCases(exprStr string, evalTime time.Time) ([]atModifierTestCa
 	// If there is a subquery, then the selectors inside it don't get the @ timestamp.
 	// If any selector already has the @ timestamp set, then it is untouched.
 	parser.Inspect(expr, func(node parser.Node, path []parser.Node) error {
-		_, _, subqTs := subqueryTimes(path)
-		if subqTs != nil {
+		if hasAtModifier(path) {
 			// There is a subquery with timestamp in the path,
 			// hence don't change any timestamps further.
 			return nil
@@ -727,6 +726,17 @@ func atModifierTestCases(exprStr string, evalTime time.Time) ([]atModifierTestCa
 	return testCases, nil
 }
 
+func hasAtModifier(path []parser.Node) bool {
+	for _, node := range path {
+		if n, ok := node.(*parser.SubqueryExpr); ok {
+			if n.Timestamp != nil {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 // exec processes a single step of the test.
 func (t *test) exec(tc testCommand, engine QueryEngine) error {
 	switch cmd := tc.(type) {

From 11b27d5d229d7ee815bd7cfc77c6682b1f3eed0c Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 10:44:53 +0100
Subject: [PATCH 04/13] test: move test files into new promqltest package

So that promql package does not bring in test-only dependencies.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/{ => promqltest}/test.go                         | 0
 promql/{ => promqltest}/testdata/aggregators.test       | 0
 promql/{ => promqltest}/testdata/at_modifier.test       | 0
 promql/{ => promqltest}/testdata/collision.test         | 0
 promql/{ => promqltest}/testdata/functions.test         | 0
 promql/{ => promqltest}/testdata/histograms.test        | 0
 promql/{ => promqltest}/testdata/literals.test          | 0
 promql/{ => promqltest}/testdata/native_histograms.test | 0
 promql/{ => promqltest}/testdata/operators.test         | 0
 promql/{ => promqltest}/testdata/selectors.test         | 0
 promql/{ => promqltest}/testdata/staleness.test         | 0
 promql/{ => promqltest}/testdata/subquery.test          | 0
 promql/{ => promqltest}/testdata/trig_functions.test    | 0
 13 files changed, 0 insertions(+), 0 deletions(-)
 rename promql/{ => promqltest}/test.go (100%)
 rename promql/{ => promqltest}/testdata/aggregators.test (100%)
 rename promql/{ => promqltest}/testdata/at_modifier.test (100%)
 rename promql/{ => promqltest}/testdata/collision.test (100%)
 rename promql/{ => promqltest}/testdata/functions.test (100%)
 rename promql/{ => promqltest}/testdata/histograms.test (100%)
 rename promql/{ => promqltest}/testdata/literals.test (100%)
 rename promql/{ => promqltest}/testdata/native_histograms.test (100%)
 rename promql/{ => promqltest}/testdata/operators.test (100%)
 rename promql/{ => promqltest}/testdata/selectors.test (100%)
 rename promql/{ => promqltest}/testdata/staleness.test (100%)
 rename promql/{ => promqltest}/testdata/subquery.test (100%)
 rename promql/{ => promqltest}/testdata/trig_functions.test (100%)

diff --git a/promql/test.go b/promql/promqltest/test.go
similarity index 100%
rename from promql/test.go
rename to promql/promqltest/test.go
diff --git a/promql/testdata/aggregators.test b/promql/promqltest/testdata/aggregators.test
similarity index 100%
rename from promql/testdata/aggregators.test
rename to promql/promqltest/testdata/aggregators.test
diff --git a/promql/testdata/at_modifier.test b/promql/promqltest/testdata/at_modifier.test
similarity index 100%
rename from promql/testdata/at_modifier.test
rename to promql/promqltest/testdata/at_modifier.test
diff --git a/promql/testdata/collision.test b/promql/promqltest/testdata/collision.test
similarity index 100%
rename from promql/testdata/collision.test
rename to promql/promqltest/testdata/collision.test
diff --git a/promql/testdata/functions.test b/promql/promqltest/testdata/functions.test
similarity index 100%
rename from promql/testdata/functions.test
rename to promql/promqltest/testdata/functions.test
diff --git a/promql/testdata/histograms.test b/promql/promqltest/testdata/histograms.test
similarity index 100%
rename from promql/testdata/histograms.test
rename to promql/promqltest/testdata/histograms.test
diff --git a/promql/testdata/literals.test b/promql/promqltest/testdata/literals.test
similarity index 100%
rename from promql/testdata/literals.test
rename to promql/promqltest/testdata/literals.test
diff --git a/promql/testdata/native_histograms.test b/promql/promqltest/testdata/native_histograms.test
similarity index 100%
rename from promql/testdata/native_histograms.test
rename to promql/promqltest/testdata/native_histograms.test
diff --git a/promql/testdata/operators.test b/promql/promqltest/testdata/operators.test
similarity index 100%
rename from promql/testdata/operators.test
rename to promql/promqltest/testdata/operators.test
diff --git a/promql/testdata/selectors.test b/promql/promqltest/testdata/selectors.test
similarity index 100%
rename from promql/testdata/selectors.test
rename to promql/promqltest/testdata/selectors.test
diff --git a/promql/testdata/staleness.test b/promql/promqltest/testdata/staleness.test
similarity index 100%
rename from promql/testdata/staleness.test
rename to promql/promqltest/testdata/staleness.test
diff --git a/promql/testdata/subquery.test b/promql/promqltest/testdata/subquery.test
similarity index 100%
rename from promql/testdata/subquery.test
rename to promql/promqltest/testdata/subquery.test
diff --git a/promql/testdata/trig_functions.test b/promql/promqltest/testdata/trig_functions.test
similarity index 100%
rename from promql/testdata/trig_functions.test
rename to promql/promqltest/testdata/trig_functions.test

From ccf73266f03a7de3fbd7d150ee80ee9521ba17a1 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 13:02:59 +0100
Subject: [PATCH 05/13] test: move promqltest tests together with the
 implementation

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/{ => promqltest}/test_test.go | 67 ++++++++++++++--------------
 1 file changed, 34 insertions(+), 33 deletions(-)
 rename promql/{ => promqltest}/test_test.go (91%)

diff --git a/promql/test_test.go b/promql/promqltest/test_test.go
similarity index 91%
rename from promql/test_test.go
rename to promql/promqltest/test_test.go
index a5b24ac69..bad3e2f3b 100644
--- a/promql/test_test.go
+++ b/promql/promqltest/test_test.go
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package promql
+package promqltest
 
 import (
 	"math"
@@ -21,14 +21,15 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/prometheus/prometheus/model/labels"
+	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/tsdb/chunkenc"
 )
 
 func TestLazyLoader_WithSamplesTill(t *testing.T) {
 	type testCase struct {
 		ts             time.Time
-		series         []Series // Each series is checked separately. Need not mention all series here.
-		checkOnlyError bool     // If this is true, series is not checked.
+		series         []promql.Series // Each series is checked separately. Need not mention all series here.
+		checkOnlyError bool            // If this is true, series is not checked.
 	}
 
 	cases := []struct {
@@ -44,10 +45,10 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 			testCases: []testCase{
 				{
 					ts: time.Unix(40, 0),
-					series: []Series{
+					series: []promql.Series{
 						{
 							Metric: labels.FromStrings("__name__", "metric1"),
-							Floats: []FPoint{
+							Floats: []promql.FPoint{
 								{0, 1}, {10000, 2}, {20000, 3}, {30000, 4}, {40000, 5},
 							},
 						},
@@ -55,10 +56,10 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 				},
 				{
 					ts: time.Unix(10, 0),
-					series: []Series{
+					series: []promql.Series{
 						{
 							Metric: labels.FromStrings("__name__", "metric1"),
-							Floats: []FPoint{
+							Floats: []promql.FPoint{
 								{0, 1}, {10000, 2}, {20000, 3}, {30000, 4}, {40000, 5},
 							},
 						},
@@ -66,10 +67,10 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 				},
 				{
 					ts: time.Unix(60, 0),
-					series: []Series{
+					series: []promql.Series{
 						{
 							Metric: labels.FromStrings("__name__", "metric1"),
-							Floats: []FPoint{
+							Floats: []promql.FPoint{
 								{0, 1}, {10000, 2}, {20000, 3}, {30000, 4}, {40000, 5}, {50000, 6}, {60000, 7},
 							},
 						},
@@ -86,16 +87,16 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 			testCases: []testCase{
 				{ // Adds all samples of metric1.
 					ts: time.Unix(70, 0),
-					series: []Series{
+					series: []promql.Series{
 						{
 							Metric: labels.FromStrings("__name__", "metric1"),
-							Floats: []FPoint{
+							Floats: []promql.FPoint{
 								{0, 1}, {10000, 1}, {20000, 1}, {30000, 1}, {40000, 1}, {50000, 1},
 							},
 						},
 						{
 							Metric: labels.FromStrings("__name__", "metric2"),
-							Floats: []FPoint{
+							Floats: []promql.FPoint{
 								{0, 1}, {10000, 2}, {20000, 3}, {30000, 4}, {40000, 5}, {50000, 6}, {60000, 7}, {70000, 8},
 							},
 						},
@@ -140,13 +141,13 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 					require.False(t, ss.Next(), "Expecting only 1 series")
 
 					// Convert `storage.Series` to `promql.Series`.
-					got := Series{
+					got := promql.Series{
 						Metric: storageSeries.Labels(),
 					}
 					it := storageSeries.Iterator(nil)
 					for it.Next() == chunkenc.ValFloat {
 						t, v := it.At()
-						got.Floats = append(got.Floats, FPoint{T: t, F: v})
+						got.Floats = append(got.Floats, promql.FPoint{T: t, F: v})
 					}
 					require.NoError(t, it.Err())
 
@@ -450,7 +451,7 @@ eval range from 0 to 5m step 5m testmetric
 
 	for name, testCase := range testCases {
 		t.Run(name, func(t *testing.T) {
-			err := runTest(t, testCase.input, newTestEngine())
+			err := runTest(t, testCase.input, NewTestEngine())
 
 			if testCase.expectedError == "" {
 				require.NoError(t, err)
@@ -463,42 +464,42 @@ eval range from 0 to 5m step 5m testmetric
 
 func TestAssertMatrixSorted(t *testing.T) {
 	testCases := map[string]struct {
-		matrix        Matrix
+		matrix        promql.Matrix
 		expectedError string
 	}{
 		"empty matrix": {
-			matrix: Matrix{},
+			matrix: promql.Matrix{},
 		},
 		"matrix with one series": {
-			matrix: Matrix{
-				Series{Metric: labels.FromStrings("the_label", "value_1")},
+			matrix: promql.Matrix{
+				promql.Series{Metric: labels.FromStrings("the_label", "value_1")},
 			},
 		},
 		"matrix with two series, series in sorted order": {
-			matrix: Matrix{
-				Series{Metric: labels.FromStrings("the_label", "value_1")},
-				Series{Metric: labels.FromStrings("the_label", "value_2")},
+			matrix: promql.Matrix{
+				promql.Series{Metric: labels.FromStrings("the_label", "value_1")},
+				promql.Series{Metric: labels.FromStrings("the_label", "value_2")},
 			},
 		},
 		"matrix with two series, series in reverse order": {
-			matrix: Matrix{
-				Series{Metric: labels.FromStrings("the_label", "value_2")},
-				Series{Metric: labels.FromStrings("the_label", "value_1")},
+			matrix: promql.Matrix{
+				promql.Series{Metric: labels.FromStrings("the_label", "value_2")},
+				promql.Series{Metric: labels.FromStrings("the_label", "value_1")},
 			},
 			expectedError: `matrix results should always be sorted by labels, but matrix is not sorted: series at index 1 with labels {the_label="value_1"} sorts before series at index 0 with labels {the_label="value_2"}`,
 		},
 		"matrix with three series, series in sorted order": {
-			matrix: Matrix{
-				Series{Metric: labels.FromStrings("the_label", "value_1")},
-				Series{Metric: labels.FromStrings("the_label", "value_2")},
-				Series{Metric: labels.FromStrings("the_label", "value_3")},
+			matrix: promql.Matrix{
+				promql.Series{Metric: labels.FromStrings("the_label", "value_1")},
+				promql.Series{Metric: labels.FromStrings("the_label", "value_2")},
+				promql.Series{Metric: labels.FromStrings("the_label", "value_3")},
 			},
 		},
 		"matrix with three series, series not in sorted order": {
-			matrix: Matrix{
-				Series{Metric: labels.FromStrings("the_label", "value_1")},
-				Series{Metric: labels.FromStrings("the_label", "value_3")},
-				Series{Metric: labels.FromStrings("the_label", "value_2")},
+			matrix: promql.Matrix{
+				promql.Series{Metric: labels.FromStrings("the_label", "value_1")},
+				promql.Series{Metric: labels.FromStrings("the_label", "value_3")},
+				promql.Series{Metric: labels.FromStrings("the_label", "value_2")},
 			},
 			expectedError: `matrix results should always be sorted by labels, but matrix is not sorted: series at index 2 with labels {the_label="value_2"} sorts before series at index 1 with labels {the_label="value_3"}`,
 		},

From 9aa321d67236ab43c1c9ca69577fd361b87e2405 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 13:40:14 +0100
Subject: [PATCH 06/13] test: make field initializers explicit

Lint started complaining after I moved the file.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/promqltest/test_test.go | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/promql/promqltest/test_test.go b/promql/promqltest/test_test.go
index bad3e2f3b..d28f556f2 100644
--- a/promql/promqltest/test_test.go
+++ b/promql/promqltest/test_test.go
@@ -49,7 +49,7 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 						{
 							Metric: labels.FromStrings("__name__", "metric1"),
 							Floats: []promql.FPoint{
-								{0, 1}, {10000, 2}, {20000, 3}, {30000, 4}, {40000, 5},
+								{T: 0, F: 1}, {T: 10000, F: 2}, {T: 20000, F: 3}, {T: 30000, F: 4}, {T: 40000, F: 5},
 							},
 						},
 					},
@@ -60,7 +60,7 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 						{
 							Metric: labels.FromStrings("__name__", "metric1"),
 							Floats: []promql.FPoint{
-								{0, 1}, {10000, 2}, {20000, 3}, {30000, 4}, {40000, 5},
+								{T: 0, F: 1}, {T: 10000, F: 2}, {T: 20000, F: 3}, {T: 30000, F: 4}, {T: 40000, F: 5},
 							},
 						},
 					},
@@ -71,7 +71,7 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 						{
 							Metric: labels.FromStrings("__name__", "metric1"),
 							Floats: []promql.FPoint{
-								{0, 1}, {10000, 2}, {20000, 3}, {30000, 4}, {40000, 5}, {50000, 6}, {60000, 7},
+								{T: 0, F: 1}, {T: 10000, F: 2}, {T: 20000, F: 3}, {T: 30000, F: 4}, {T: 40000, F: 5}, {T: 50000, F: 6}, {T: 60000, F: 7},
 							},
 						},
 					},
@@ -91,13 +91,13 @@ func TestLazyLoader_WithSamplesTill(t *testing.T) {
 						{
 							Metric: labels.FromStrings("__name__", "metric1"),
 							Floats: []promql.FPoint{
-								{0, 1}, {10000, 1}, {20000, 1}, {30000, 1}, {40000, 1}, {50000, 1},
+								{T: 0, F: 1}, {T: 10000, F: 1}, {T: 20000, F: 1}, {T: 30000, F: 1}, {T: 40000, F: 1}, {T: 50000, F: 1},
 							},
 						},
 						{
 							Metric: labels.FromStrings("__name__", "metric2"),
 							Floats: []promql.FPoint{
-								{0, 1}, {10000, 2}, {20000, 3}, {30000, 4}, {40000, 5}, {50000, 6}, {60000, 7}, {70000, 8},
+								{T: 0, F: 1}, {T: 10000, F: 2}, {T: 20000, F: 3}, {T: 30000, F: 4}, {T: 40000, F: 5}, {T: 50000, F: 6}, {T: 60000, F: 7}, {T: 70000, F: 8},
 							},
 						},
 					},

From b3c15d2246e9652f08c2b6030b82f8aaa943849e Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 10:47:45 +0100
Subject: [PATCH 07/13] test: clean up promqltest package references

So it nearly compiles.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/promqltest/test.go | 81 +++++++++++++++++++++++----------------
 1 file changed, 48 insertions(+), 33 deletions(-)

diff --git a/promql/promqltest/test.go b/promql/promqltest/test.go
index 2cfcfce6f..eab26ad57 100644
--- a/promql/promqltest/test.go
+++ b/promql/promqltest/test.go
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package promql
+package promqltest
 
 import (
 	"context"
@@ -32,6 +32,7 @@ import (
 	"github.com/prometheus/prometheus/model/histogram"
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/model/timestamp"
+	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
 	"github.com/prometheus/prometheus/promql/parser/posrange"
 	"github.com/prometheus/prometheus/storage"
@@ -71,7 +72,7 @@ func LoadedStorage(t testutil.T, input string) *teststorage.TestStorage {
 }
 
 // RunBuiltinTests runs an acceptance test suite against the provided engine.
-func RunBuiltinTests(t *testing.T, engine QueryEngine) {
+func RunBuiltinTests(t *testing.T, engine promql.QueryEngine) {
 	t.Cleanup(func() { parser.EnableExperimentalFunctions = false })
 	parser.EnableExperimentalFunctions = true
 
@@ -88,11 +89,11 @@ func RunBuiltinTests(t *testing.T, engine QueryEngine) {
 }
 
 // RunTest parses and runs the test against the provided engine.
-func RunTest(t testutil.T, input string, engine QueryEngine) {
+func RunTest(t testutil.T, input string, engine promql.QueryEngine) {
 	require.NoError(t, runTest(t, input, engine))
 }
 
-func runTest(t testutil.T, input string, engine QueryEngine) error {
+func runTest(t testutil.T, input string, engine promql.QueryEngine) error {
 	test, err := newTest(t, input)
 
 	// Why do this before checking err? newTest() can create the test storage and then return an error,
@@ -366,7 +367,7 @@ func (*evalCmd) testCmd()  {}
 type loadCmd struct {
 	gap       time.Duration
 	metrics   map[uint64]labels.Labels
-	defs      map[uint64][]Sample
+	defs      map[uint64][]promql.Sample
 	exemplars map[uint64][]exemplar.Exemplar
 }
 
@@ -374,7 +375,7 @@ func newLoadCmd(gap time.Duration) *loadCmd {
 	return &loadCmd{
 		gap:       gap,
 		metrics:   map[uint64]labels.Labels{},
-		defs:      map[uint64][]Sample{},
+		defs:      map[uint64][]promql.Sample{},
 		exemplars: map[uint64][]exemplar.Exemplar{},
 	}
 }
@@ -387,11 +388,11 @@ func (cmd loadCmd) String() string {
 func (cmd *loadCmd) set(m labels.Labels, vals ...parser.SequenceValue) {
 	h := m.Hash()
 
-	samples := make([]Sample, 0, len(vals))
+	samples := make([]promql.Sample, 0, len(vals))
 	ts := testStartTime
 	for _, v := range vals {
 		if !v.Omitted {
-			samples = append(samples, Sample{
+			samples = append(samples, promql.Sample{
 				T: ts.UnixNano() / int64(time.Millisecond/time.Nanosecond),
 				F: v.Value,
 				H: v.Histogram,
@@ -417,7 +418,7 @@ func (cmd *loadCmd) append(a storage.Appender) error {
 	return nil
 }
 
-func appendSample(a storage.Appender, s Sample, m labels.Labels) error {
+func appendSample(a storage.Appender, s promql.Sample, m labels.Labels) error {
 	if s.H != nil {
 		if _, err := a.AppendHistogram(0, m, s.T, nil, s.H); err != nil {
 			return err
@@ -501,7 +502,7 @@ func (ev *evalCmd) expectMetric(pos int, m labels.Labels, vals ...parser.Sequenc
 // compareResult compares the result value with the defined expectation.
 func (ev *evalCmd) compareResult(result parser.Value) error {
 	switch val := result.(type) {
-	case Matrix:
+	case promql.Matrix:
 		if ev.ordered {
 			return fmt.Errorf("expected ordered result, but query returned a matrix")
 		}
@@ -519,8 +520,8 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 			seen[hash] = true
 			exp := ev.expected[hash]
 
-			var expectedFloats []FPoint
-			var expectedHistograms []HPoint
+			var expectedFloats []promql.FPoint
+			var expectedHistograms []promql.HPoint
 
 			for i, e := range exp.vals {
 				ts := ev.start.Add(time.Duration(i) * ev.step)
@@ -532,9 +533,9 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 				t := ts.UnixNano() / int64(time.Millisecond/time.Nanosecond)
 
 				if e.Histogram != nil {
-					expectedHistograms = append(expectedHistograms, HPoint{T: t, H: e.Histogram})
+					expectedHistograms = append(expectedHistograms, promql.HPoint{T: t, H: e.Histogram})
 				} else if !e.Omitted {
-					expectedFloats = append(expectedFloats, FPoint{T: t, F: e.Value})
+					expectedFloats = append(expectedFloats, promql.FPoint{T: t, F: e.Value})
 				}
 			}
 
@@ -573,7 +574,7 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 			}
 		}
 
-	case Vector:
+	case promql.Vector:
 		seen := map[uint64]bool{}
 		for pos, v := range val {
 			fp := v.Metric.Hash()
@@ -611,7 +612,7 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 			}
 		}
 
-	case Scalar:
+	case promql.Scalar:
 		if len(ev.expected) != 1 {
 			return fmt.Errorf("expected vector result, but got scalar %s", val.String())
 		}
@@ -629,7 +630,7 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 	return nil
 }
 
-func formatSeriesResult(s Series) string {
+func formatSeriesResult(s promql.Series) string {
 	floatPlural := "s"
 	histogramPlural := "s"
 
@@ -698,7 +699,7 @@ func atModifierTestCases(exprStr string, evalTime time.Time) ([]atModifierTestCa
 			}
 
 		case *parser.Call:
-			_, ok := AtModifierUnsafeFunctions[n.Func.Name]
+			_, ok := promql.AtModifierUnsafeFunctions[n.Func.Name]
 			containsNonStepInvariant = containsNonStepInvariant || ok
 		}
 		return nil
@@ -738,7 +739,7 @@ func hasAtModifier(path []parser.Node) bool {
 }
 
 // exec processes a single step of the test.
-func (t *test) exec(tc testCommand, engine QueryEngine) error {
+func (t *test) exec(tc testCommand, engine promql.QueryEngine) error {
 	switch cmd := tc.(type) {
 	case *clearCmd:
 		t.clear()
@@ -763,7 +764,7 @@ func (t *test) exec(tc testCommand, engine QueryEngine) error {
 	return nil
 }
 
-func (t *test) execEval(cmd *evalCmd, engine QueryEngine) error {
+func (t *test) execEval(cmd *evalCmd, engine promql.QueryEngine) error {
 	if cmd.isRange {
 		return t.execRangeEval(cmd, engine)
 	}
@@ -771,7 +772,7 @@ func (t *test) execEval(cmd *evalCmd, engine QueryEngine) error {
 	return t.execInstantEval(cmd, engine)
 }
 
-func (t *test) execRangeEval(cmd *evalCmd, engine QueryEngine) error {
+func (t *test) execRangeEval(cmd *evalCmd, engine promql.QueryEngine) error {
 	q, err := engine.NewRangeQuery(t.context, t.storage, nil, cmd.expr, cmd.start, cmd.end, cmd.step)
 	if err != nil {
 		return fmt.Errorf("error creating range query for %q (line %d): %w", cmd.expr, cmd.line, err)
@@ -796,7 +797,7 @@ func (t *test) execRangeEval(cmd *evalCmd, engine QueryEngine) error {
 	return nil
 }
 
-func (t *test) execInstantEval(cmd *evalCmd, engine QueryEngine) error {
+func (t *test) execInstantEval(cmd *evalCmd, engine promql.QueryEngine) error {
 	queries, err := atModifierTestCases(cmd.expr, cmd.start)
 	if err != nil {
 		return err
@@ -838,29 +839,29 @@ func (t *test) execInstantEval(cmd *evalCmd, engine QueryEngine) error {
 			// Range queries are always sorted by labels, so skip this test case that expects results in a particular order.
 			continue
 		}
-		mat := rangeRes.Value.(Matrix)
+		mat := rangeRes.Value.(promql.Matrix)
 		if err := assertMatrixSorted(mat); err != nil {
 			return err
 		}
 
-		vec := make(Vector, 0, len(mat))
+		vec := make(promql.Vector, 0, len(mat))
 		for _, series := range mat {
 			// We expect either Floats or Histograms.
 			for _, point := range series.Floats {
 				if point.T == timeMilliseconds(iq.evalTime) {
-					vec = append(vec, Sample{Metric: series.Metric, T: point.T, F: point.F})
+					vec = append(vec, promql.Sample{Metric: series.Metric, T: point.T, F: point.F})
 					break
 				}
 			}
 			for _, point := range series.Histograms {
 				if point.T == timeMilliseconds(iq.evalTime) {
-					vec = append(vec, Sample{Metric: series.Metric, T: point.T, H: point.H})
+					vec = append(vec, promql.Sample{Metric: series.Metric, T: point.T, H: point.H})
 					break
 				}
 			}
 		}
-		if _, ok := res.Value.(Scalar); ok {
-			err = cmd.compareResult(Scalar{V: vec[0].F})
+		if _, ok := res.Value.(promql.Scalar); ok {
+			err = cmd.compareResult(promql.Scalar{V: vec[0].F})
 		} else {
 			err = cmd.compareResult(vec)
 		}
@@ -872,7 +873,7 @@ func (t *test) execInstantEval(cmd *evalCmd, engine QueryEngine) error {
 	return nil
 }
 
-func assertMatrixSorted(m Matrix) error {
+func assertMatrixSorted(m promql.Matrix) error {
 	if len(m) <= 1 {
 		return nil
 	}
@@ -922,7 +923,7 @@ type LazyLoader struct {
 	storage          storage.Storage
 	SubqueryInterval time.Duration
 
-	queryEngine *Engine
+	queryEngine *promql.Engine
 	context     context.Context
 	cancelCtx   context.CancelFunc
 
@@ -989,7 +990,7 @@ func (ll *LazyLoader) clear() error {
 		return err
 	}
 
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:                   nil,
 		Reg:                      nil,
 		MaxSamples:               10000,
@@ -999,7 +1000,7 @@ func (ll *LazyLoader) clear() error {
 		EnableNegativeOffset:     ll.opts.EnableNegativeOffset,
 	}
 
-	ll.queryEngine = NewEngine(opts)
+	ll.queryEngine = promql.NewEngine(opts)
 	ll.context, ll.cancelCtx = context.WithCancel(context.Background())
 	return nil
 }
@@ -1033,7 +1034,7 @@ func (ll *LazyLoader) WithSamplesTill(ts time.Time, fn func(error)) {
 }
 
 // QueryEngine returns the LazyLoader's query engine.
-func (ll *LazyLoader) QueryEngine() *Engine {
+func (ll *LazyLoader) QueryEngine() *promql.Engine {
 	return ll.queryEngine
 }
 
@@ -1059,3 +1060,17 @@ func (ll *LazyLoader) Close() error {
 	ll.cancelCtx()
 	return ll.storage.Close()
 }
+
+func makeInt64Pointer(val int64) *int64 {
+	valp := new(int64)
+	*valp = val
+	return valp
+}
+
+func timeMilliseconds(t time.Time) int64 {
+	return t.UnixNano() / int64(time.Millisecond/time.Nanosecond)
+}
+
+func durationMilliseconds(d time.Duration) int64 {
+	return int64(d / (time.Millisecond / time.Nanosecond))
+}

From babfcfdd910ef2d3e829ae05bac766c1c4e3952b Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 13:13:23 +0100
Subject: [PATCH 08/13] refactor: Move NewTestEngine into promqltest

And export `DefaultMaxSamplesPerQuery` so callers can replicate previous
behaviour.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/engine_test.go          |  2 +-
 promql/promql_test.go          | 12 ++----------
 promql/promqltest/test.go      | 17 ++++++++++++++++-
 promql/promqltest/test_test.go |  2 +-
 4 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/promql/engine_test.go b/promql/engine_test.go
index 36f36807a..1c2722a1d 100644
--- a/promql/engine_test.go
+++ b/promql/engine_test.go
@@ -4999,7 +4999,7 @@ metric 0 1 2
 			if c.engineLookback != 0 {
 				engine.lookbackDelta = c.engineLookback
 			}
-			opts := NewPrometheusQueryOpts(false, c.queryLookback)
+			opts := promql.NewPrometheusQueryOpts(false, c.queryLookback)
 			qry, err := engine.NewInstantQuery(context.Background(), storage, opts, query, c.ts)
 			require.NoError(t, err)
 
diff --git a/promql/promql_test.go b/promql/promql_test.go
index 05821b1c1..87ec2cd4e 100644
--- a/promql/promql_test.go
+++ b/promql/promql_test.go
@@ -22,20 +22,12 @@ import (
 	"github.com/stretchr/testify/require"
 	"golang.org/x/sync/errgroup"
 
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/util/teststorage"
 )
 
 func newTestEngine() *Engine {
-	return NewEngine(EngineOpts{
-		Logger:                   nil,
-		Reg:                      nil,
-		MaxSamples:               10000,
-		Timeout:                  100 * time.Second,
-		NoStepSubqueryIntervalFn: func(int64) int64 { return durationMilliseconds(1 * time.Minute) },
-		EnableAtModifier:         true,
-		EnableNegativeOffset:     true,
-		EnablePerStepStats:       true,
-	})
+	return promqltest.NewTestEngine(false, 0, promqltest.DefaultMaxSamplesPerQuery)
 }
 
 func TestEvaluations(t *testing.T) {
diff --git a/promql/promqltest/test.go b/promql/promqltest/test.go
index eab26ad57..1b2ce78af 100644
--- a/promql/promqltest/test.go
+++ b/promql/promqltest/test.go
@@ -49,7 +49,8 @@ var (
 )
 
 const (
-	defaultEpsilon = 0.000001 // Relative error allowed for sample values.
+	defaultEpsilon            = 0.000001 // Relative error allowed for sample values.
+	DefaultMaxSamplesPerQuery = 10000
 )
 
 var testStartTime = time.Unix(0, 0).UTC()
@@ -71,6 +72,20 @@ func LoadedStorage(t testutil.T, input string) *teststorage.TestStorage {
 	return test.storage
 }
 
+func NewTestEngine(enablePerStepStats bool, lookbackDelta time.Duration, maxSamples int) *promql.Engine {
+	return promql.NewEngine(promql.EngineOpts{
+		Logger:                   nil,
+		Reg:                      nil,
+		MaxSamples:               DefaultMaxSamplesPerQuery,
+		Timeout:                  100 * time.Second,
+		NoStepSubqueryIntervalFn: func(int64) int64 { return durationMilliseconds(1 * time.Minute) },
+		EnableAtModifier:         true,
+		EnableNegativeOffset:     true,
+		EnablePerStepStats:       enablePerStepStats,
+		LookbackDelta:            lookbackDelta,
+	})
+}
+
 // RunBuiltinTests runs an acceptance test suite against the provided engine.
 func RunBuiltinTests(t *testing.T, engine promql.QueryEngine) {
 	t.Cleanup(func() { parser.EnableExperimentalFunctions = false })
diff --git a/promql/promqltest/test_test.go b/promql/promqltest/test_test.go
index d28f556f2..f6fe38707 100644
--- a/promql/promqltest/test_test.go
+++ b/promql/promqltest/test_test.go
@@ -451,7 +451,7 @@ eval range from 0 to 5m step 5m testmetric
 
 	for name, testCase := range testCases {
 		t.Run(name, func(t *testing.T) {
-			err := runTest(t, testCase.input, NewTestEngine())
+			err := runTest(t, testCase.input, NewTestEngine(false, 0, DefaultMaxSamplesPerQuery))
 
 			if testCase.expectedError == "" {
 				require.NoError(t, err)

From e7c77f7b4097eb4ddcde99aed2a9296870b79052 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 12:38:27 +0100
Subject: [PATCH 09/13] promql: export NewTestQuery

So that tests can call it from another package.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/engine.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/promql/engine.go b/promql/engine.go
index b8a8ea095..08c787d5c 100644
--- a/promql/engine.go
+++ b/promql/engine.go
@@ -573,7 +573,8 @@ func (ng *Engine) validateOpts(expr parser.Expr) error {
 	return validationErr
 }
 
-func (ng *Engine) newTestQuery(f func(context.Context) error) Query {
+// NewTestQuery: inject special behaviour into Query for testing.
+func (ng *Engine) NewTestQuery(f func(context.Context) error) Query {
 	qry := &query{
 		q:           "test statement",
 		stmt:        parser.TestStmt(f),

From 8fd96241ab04d829e198ad2f6f67e33f3bf5b564 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 10:48:24 +0100
Subject: [PATCH 10/13] test: add promqltest package references

To packages outside of promql.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 cmd/promtool/main.go                |  4 ++--
 cmd/promtool/tsdb_test.go           |  6 +++---
 cmd/promtool/unittest.go            | 13 +++++++------
 cmd/promtool/unittest_test.go       | 12 ++++++------
 rules/alerting_test.go              | 17 +++++++++--------
 rules/manager_test.go               |  9 +++++----
 rules/recording_test.go             |  5 +++--
 storage/remote/read_handler_test.go |  8 ++++----
 web/api/v1/api_test.go              | 11 ++++++-----
 web/federate_test.go                |  3 ++-
 10 files changed, 47 insertions(+), 41 deletions(-)

diff --git a/cmd/promtool/main.go b/cmd/promtool/main.go
index a62ae4fbf..c0484adcc 100644
--- a/cmd/promtool/main.go
+++ b/cmd/promtool/main.go
@@ -56,8 +56,8 @@ import (
 	"github.com/prometheus/prometheus/model/rulefmt"
 	"github.com/prometheus/prometheus/notifier"
 	_ "github.com/prometheus/prometheus/plugins" // Register plugins.
-	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/scrape"
 	"github.com/prometheus/prometheus/util/documentcli"
 )
@@ -377,7 +377,7 @@ func main() {
 
 	case testRulesCmd.FullCommand():
 		os.Exit(RulesUnitTest(
-			promql.LazyLoaderOpts{
+			promqltest.LazyLoaderOpts{
 				EnableAtModifier:     true,
 				EnableNegativeOffset: true,
 			},
diff --git a/cmd/promtool/tsdb_test.go b/cmd/promtool/tsdb_test.go
index 36a65d73e..70e887765 100644
--- a/cmd/promtool/tsdb_test.go
+++ b/cmd/promtool/tsdb_test.go
@@ -26,7 +26,7 @@ import (
 
 	"github.com/stretchr/testify/require"
 
-	"github.com/prometheus/prometheus/promql"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/tsdb"
 )
 
@@ -88,7 +88,7 @@ func normalizeNewLine(b []byte) []byte {
 }
 
 func TestTSDBDump(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			metric{foo="bar", baz="abc"} 1 2 3 4 5
 			heavy_metric{foo="bar"} 5 4 3 2 1
@@ -158,7 +158,7 @@ func TestTSDBDump(t *testing.T) {
 }
 
 func TestTSDBDumpOpenMetrics(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			my_counter{foo="bar", baz="abc"} 1 2 3 4 5
 			my_gauge{bar="foo", abc="baz"} 9 8 0 4 7
diff --git a/cmd/promtool/unittest.go b/cmd/promtool/unittest.go
index 6d6683a93..27d5dd98b 100644
--- a/cmd/promtool/unittest.go
+++ b/cmd/promtool/unittest.go
@@ -36,13 +36,14 @@ import (
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/rules"
 	"github.com/prometheus/prometheus/storage"
 )
 
 // RulesUnitTest does unit testing of rules based on the unit testing files provided.
 // More info about the file format can be found in the docs.
-func RulesUnitTest(queryOpts promql.LazyLoaderOpts, runStrings []string, diffFlag bool, files ...string) int {
+func RulesUnitTest(queryOpts promqltest.LazyLoaderOpts, runStrings []string, diffFlag bool, files ...string) int {
 	failed := false
 
 	var run *regexp.Regexp
@@ -69,7 +70,7 @@ func RulesUnitTest(queryOpts promql.LazyLoaderOpts, runStrings []string, diffFla
 	return successExitCode
 }
 
-func ruleUnitTest(filename string, queryOpts promql.LazyLoaderOpts, run *regexp.Regexp, diffFlag bool) []error {
+func ruleUnitTest(filename string, queryOpts promqltest.LazyLoaderOpts, run *regexp.Regexp, diffFlag bool) []error {
 	fmt.Println("Unit Testing: ", filename)
 
 	b, err := os.ReadFile(filename)
@@ -175,9 +176,9 @@ type testGroup struct {
 }
 
 // test performs the unit tests.
-func (tg *testGroup) test(evalInterval time.Duration, groupOrderMap map[string]int, queryOpts promql.LazyLoaderOpts, diffFlag bool, ruleFiles ...string) (outErr []error) {
+func (tg *testGroup) test(evalInterval time.Duration, groupOrderMap map[string]int, queryOpts promqltest.LazyLoaderOpts, diffFlag bool, ruleFiles ...string) (outErr []error) {
 	// Setup testing suite.
-	suite, err := promql.NewLazyLoader(tg.seriesLoadingString(), queryOpts)
+	suite, err := promqltest.NewLazyLoader(tg.seriesLoadingString(), queryOpts)
 	if err != nil {
 		return []error{err}
 	}
@@ -413,7 +414,7 @@ Outer:
 			gotSamples = append(gotSamples, parsedSample{
 				Labels:    s.Metric.Copy(),
 				Value:     s.F,
-				Histogram: promql.HistogramTestExpression(s.H),
+				Histogram: promqltest.HistogramTestExpression(s.H),
 			})
 		}
 
@@ -443,7 +444,7 @@ Outer:
 			expSamples = append(expSamples, parsedSample{
 				Labels:    lb,
 				Value:     s.Value,
-				Histogram: promql.HistogramTestExpression(hist),
+				Histogram: promqltest.HistogramTestExpression(hist),
 			})
 		}
 
diff --git a/cmd/promtool/unittest_test.go b/cmd/promtool/unittest_test.go
index 971ddb40c..2dbd5a4e5 100644
--- a/cmd/promtool/unittest_test.go
+++ b/cmd/promtool/unittest_test.go
@@ -18,7 +18,7 @@ import (
 
 	"github.com/stretchr/testify/require"
 
-	"github.com/prometheus/prometheus/promql"
+	"github.com/prometheus/prometheus/promql/promqltest"
 )
 
 func TestRulesUnitTest(t *testing.T) {
@@ -28,7 +28,7 @@ func TestRulesUnitTest(t *testing.T) {
 	tests := []struct {
 		name      string
 		args      args
-		queryOpts promql.LazyLoaderOpts
+		queryOpts promqltest.LazyLoaderOpts
 		want      int
 	}{
 		{
@@ -92,7 +92,7 @@ func TestRulesUnitTest(t *testing.T) {
 			args: args{
 				files: []string{"./testdata/at-modifier-test.yml"},
 			},
-			queryOpts: promql.LazyLoaderOpts{
+			queryOpts: promqltest.LazyLoaderOpts{
 				EnableAtModifier: true,
 			},
 			want: 0,
@@ -109,7 +109,7 @@ func TestRulesUnitTest(t *testing.T) {
 			args: args{
 				files: []string{"./testdata/negative-offset-test.yml"},
 			},
-			queryOpts: promql.LazyLoaderOpts{
+			queryOpts: promqltest.LazyLoaderOpts{
 				EnableNegativeOffset: true,
 			},
 			want: 0,
@@ -119,7 +119,7 @@ func TestRulesUnitTest(t *testing.T) {
 			args: args{
 				files: []string{"./testdata/no-test-group-interval.yml"},
 			},
-			queryOpts: promql.LazyLoaderOpts{
+			queryOpts: promqltest.LazyLoaderOpts{
 				EnableNegativeOffset: true,
 			},
 			want: 0,
@@ -142,7 +142,7 @@ func TestRulesUnitTestRun(t *testing.T) {
 	tests := []struct {
 		name      string
 		args      args
-		queryOpts promql.LazyLoaderOpts
+		queryOpts promqltest.LazyLoaderOpts
 		want      int
 	}{
 		{
diff --git a/rules/alerting_test.go b/rules/alerting_test.go
index 5fae3edd1..a9315b47e 100644
--- a/rules/alerting_test.go
+++ b/rules/alerting_test.go
@@ -30,6 +30,7 @@ import (
 	"github.com/prometheus/prometheus/notifier"
 	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/util/teststorage"
 	"github.com/prometheus/prometheus/util/testutil"
@@ -148,7 +149,7 @@ func TestAlertingRuleTemplateWithHistogram(t *testing.T) {
 }
 
 func TestAlertingRuleLabelsUpdate(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			http_requests{job="app-server", instance="0"}	75 85 70 70 stale
 	`)
@@ -252,7 +253,7 @@ func TestAlertingRuleLabelsUpdate(t *testing.T) {
 }
 
 func TestAlertingRuleExternalLabelsInTemplate(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			http_requests{job="app-server", instance="0"}	75 85 70 70
 	`)
@@ -345,7 +346,7 @@ func TestAlertingRuleExternalLabelsInTemplate(t *testing.T) {
 }
 
 func TestAlertingRuleExternalURLInTemplate(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			http_requests{job="app-server", instance="0"}	75 85 70 70
 	`)
@@ -438,7 +439,7 @@ func TestAlertingRuleExternalURLInTemplate(t *testing.T) {
 }
 
 func TestAlertingRuleEmptyLabelFromTemplate(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			http_requests{job="app-server", instance="0"}	75 85 70 70
 	`)
@@ -492,7 +493,7 @@ func TestAlertingRuleEmptyLabelFromTemplate(t *testing.T) {
 }
 
 func TestAlertingRuleQueryInTemplate(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			http_requests{job="app-server", instance="0"}	70 85 70 70
 	`)
@@ -601,7 +602,7 @@ func TestAlertingRuleDuplicate(t *testing.T) {
 }
 
 func TestAlertingRuleLimit(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			metric{label="1"} 1
 			metric{label="2"} 1
@@ -783,7 +784,7 @@ func TestSendAlertsDontAffectActiveAlerts(t *testing.T) {
 }
 
 func TestKeepFiringFor(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			http_requests{job="app-server", instance="0"}	75 85 70 70 10x5
 	`)
@@ -893,7 +894,7 @@ func TestKeepFiringFor(t *testing.T) {
 }
 
 func TestPendingAndKeepFiringFor(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			http_requests{job="app-server", instance="0"}	75 10x10
 	`)
diff --git a/rules/manager_test.go b/rules/manager_test.go
index 07159145f..665b1379a 100644
--- a/rules/manager_test.go
+++ b/rules/manager_test.go
@@ -38,6 +38,7 @@ import (
 	"github.com/prometheus/prometheus/model/value"
 	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/chunkenc"
 	"github.com/prometheus/prometheus/tsdb/tsdbutil"
@@ -50,7 +51,7 @@ func TestMain(m *testing.M) {
 }
 
 func TestAlertingRule(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 5m
 			http_requests{job="app-server", instance="0", group="canary", severity="overwrite-me"}	75 85  95 105 105  95  85
 			http_requests{job="app-server", instance="1", group="canary", severity="overwrite-me"}	80 90 100 110 120 130 140
@@ -190,7 +191,7 @@ func TestAlertingRule(t *testing.T) {
 }
 
 func TestForStateAddSamples(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 5m
 			http_requests{job="app-server", instance="0", group="canary", severity="overwrite-me"}	75 85  95 105 105  95  85
 			http_requests{job="app-server", instance="1", group="canary", severity="overwrite-me"}	80 90 100 110 120 130 140
@@ -347,7 +348,7 @@ func sortAlerts(items []*Alert) {
 }
 
 func TestForStateRestore(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 5m
 		http_requests{job="app-server", instance="0", group="canary", severity="overwrite-me"}	75  85 50 0 0 25 0 0 40 0 120
 		http_requests{job="app-server", instance="1", group="canary", severity="overwrite-me"}	125 90 60 0 0 25 0 0 40 0 130
@@ -1229,7 +1230,7 @@ func TestRuleHealthUpdates(t *testing.T) {
 }
 
 func TestRuleGroupEvalIterationFunc(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 5m
 		http_requests{instance="0"}	75  85 50 0 0 25 0 0 40 0 120
 	`)
diff --git a/rules/recording_test.go b/rules/recording_test.go
index 24b7d6539..49f37b1ac 100644
--- a/rules/recording_test.go
+++ b/rules/recording_test.go
@@ -24,6 +24,7 @@ import (
 	"github.com/prometheus/prometheus/model/timestamp"
 	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/util/teststorage"
 	"github.com/prometheus/prometheus/util/testutil"
 )
@@ -111,7 +112,7 @@ var ruleEvalTestScenarios = []struct {
 }
 
 func setUpRuleEvalTest(t require.TestingT) *teststorage.TestStorage {
-	return promql.LoadedStorage(t, `
+	return promqltest.LoadedStorage(t, `
 		load 1m
 			metric{label_a="1",label_b="3"} 1
 			metric{label_a="2",label_b="4"} 10
@@ -178,7 +179,7 @@ func TestRuleEvalDuplicate(t *testing.T) {
 }
 
 func TestRecordingRuleLimit(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			metric{label="1"} 1
 			metric{label="2"} 1
diff --git a/storage/remote/read_handler_test.go b/storage/remote/read_handler_test.go
index e8e0ecb8d..452b29221 100644
--- a/storage/remote/read_handler_test.go
+++ b/storage/remote/read_handler_test.go
@@ -30,14 +30,14 @@ import (
 	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/prompb"
-	"github.com/prometheus/prometheus/promql"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/tsdbutil"
 	"github.com/prometheus/prometheus/util/teststorage"
 )
 
 func TestSampledReadEndpoint(t *testing.T) {
-	store := promql.LoadedStorage(t, `
+	store := promqltest.LoadedStorage(t, `
 		load 1m
 			test_metric1{foo="bar",baz="qux"} 1
 	`)
@@ -132,7 +132,7 @@ func TestSampledReadEndpoint(t *testing.T) {
 }
 
 func BenchmarkStreamReadEndpoint(b *testing.B) {
-	store := promql.LoadedStorage(b, `
+	store := promqltest.LoadedStorage(b, `
 	load 1m
 		test_metric1{foo="bar1",baz="qux"} 0+100x119
 		test_metric1{foo="bar2",baz="qux"} 0+100x120
@@ -200,7 +200,7 @@ func TestStreamReadEndpoint(t *testing.T) {
 	// Second with 121 float samples, We expect 1 frame with 2 chunks.
 	// Third with 241 float samples. We expect 1 frame with 2 chunks, and 1 frame with 1 chunk for the same series due to bytes limit.
 	// Fourth with 25 histogram samples. We expect 1 frame with 1 chunk.
-	store := promql.LoadedStorage(t, `
+	store := promqltest.LoadedStorage(t, `
 		load 1m
 			test_metric1{foo="bar1",baz="qux"} 0+100x119
 			test_metric1{foo="bar2",baz="qux"} 0+100x120
diff --git a/web/api/v1/api_test.go b/web/api/v1/api_test.go
index bb2a73f6d..9d7d1d502 100644
--- a/web/api/v1/api_test.go
+++ b/web/api/v1/api_test.go
@@ -49,6 +49,7 @@ import (
 	"github.com/prometheus/prometheus/model/timestamp"
 	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/rules"
 	"github.com/prometheus/prometheus/scrape"
 	"github.com/prometheus/prometheus/storage"
@@ -338,7 +339,7 @@ var sampleFlagMap = map[string]string{
 }
 
 func TestEndpoints(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			test_metric1{foo="bar"} 0+100x100
 			test_metric1{foo="boo"} 1+0x100
@@ -502,7 +503,7 @@ func (b byLabels) Less(i, j int) bool { return labels.Compare(b[i], b[j]) < 0 }
 func TestGetSeries(t *testing.T) {
 	// TestEndpoints doesn't have enough label names to test api.labelNames
 	// endpoint properly. Hence we test it separately.
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			test_metric1{foo1="bar", baz="abc"} 0+100x100
 			test_metric1{foo2="boo"} 1+0x100
@@ -606,7 +607,7 @@ func TestGetSeries(t *testing.T) {
 
 func TestQueryExemplars(t *testing.T) {
 	start := time.Unix(0, 0)
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			test_metric1{foo="bar"} 0+100x100
 			test_metric1{foo="boo"} 1+0x100
@@ -725,7 +726,7 @@ func TestQueryExemplars(t *testing.T) {
 func TestLabelNames(t *testing.T) {
 	// TestEndpoints doesn't have enough label names to test api.labelNames
 	// endpoint properly. Hence we test it separately.
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			test_metric1{foo1="bar", baz="abc"} 0+100x100
 			test_metric1{foo2="boo"} 1+0x100
@@ -3835,7 +3836,7 @@ func TestExtractQueryOpts(t *testing.T) {
 
 // Test query timeout parameter.
 func TestQueryTimeout(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			test_metric1{foo="bar"} 0+100x100
 	`)
diff --git a/web/federate_test.go b/web/federate_test.go
index f201210ec..e5adb97eb 100644
--- a/web/federate_test.go
+++ b/web/federate_test.go
@@ -34,6 +34,7 @@ import (
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/model/textparse"
 	"github.com/prometheus/prometheus/promql"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb"
 	"github.com/prometheus/prometheus/util/teststorage"
@@ -201,7 +202,7 @@ test_metric_without_labels{instance="baz"} 1001 6000000
 }
 
 func TestFederation(t *testing.T) {
-	storage := promql.LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 		load 1m
 			test_metric1{foo="bar",instance="i"}    0+100x100
 			test_metric1{foo="boo",instance="i"}    1+0x100

From 4a72607c4a59d51042a282d02b930e355b4ac033 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 12:39:49 +0100
Subject: [PATCH 11/13] refactor: extract some PromQL Engine tests which use
 unexported structs

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/engine_internal_test.go | 82 ++++++++++++++++++++++++++++++++++
 promql/engine_test.go          | 59 ------------------------
 2 files changed, 82 insertions(+), 59 deletions(-)
 create mode 100644 promql/engine_internal_test.go

diff --git a/promql/engine_internal_test.go b/promql/engine_internal_test.go
new file mode 100644
index 000000000..cb501b2fd
--- /dev/null
+++ b/promql/engine_internal_test.go
@@ -0,0 +1,82 @@
+// Copyright 2024 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package promql
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/go-kit/log"
+	"github.com/stretchr/testify/require"
+
+	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/util/annotations"
+)
+
+func TestRecoverEvaluatorRuntime(t *testing.T) {
+	var output []interface{}
+	logger := log.Logger(log.LoggerFunc(func(keyvals ...interface{}) error {
+		output = append(output, keyvals...)
+		return nil
+	}))
+	ev := &evaluator{logger: logger}
+
+	expr, _ := parser.ParseExpr("sum(up)")
+
+	var err error
+
+	defer func() {
+		require.EqualError(t, err, "unexpected error: runtime error: index out of range [123] with length 0")
+		require.Contains(t, output, "sum(up)")
+	}()
+	defer ev.recover(expr, nil, &err)
+
+	// Cause a runtime panic.
+	var a []int
+	a[123] = 1
+}
+
+func TestRecoverEvaluatorError(t *testing.T) {
+	ev := &evaluator{logger: log.NewNopLogger()}
+	var err error
+
+	e := errors.New("custom error")
+
+	defer func() {
+		require.EqualError(t, err, e.Error())
+	}()
+	defer ev.recover(nil, nil, &err)
+
+	panic(e)
+}
+
+func TestRecoverEvaluatorErrorWithWarnings(t *testing.T) {
+	ev := &evaluator{logger: log.NewNopLogger()}
+	var err error
+	var ws annotations.Annotations
+
+	warnings := annotations.New().Add(errors.New("custom warning"))
+	e := errWithWarnings{
+		err:      errors.New("custom error"),
+		warnings: warnings,
+	}
+
+	defer func() {
+		require.EqualError(t, err, e.Error())
+		require.Equal(t, warnings, ws, "wrong warning message")
+	}()
+	defer ev.recover(nil, &ws, &err)
+
+	panic(e)
+}
diff --git a/promql/engine_test.go b/promql/engine_test.go
index 1c2722a1d..826531789 100644
--- a/promql/engine_test.go
+++ b/promql/engine_test.go
@@ -23,8 +23,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/go-kit/log"
-
 	"github.com/stretchr/testify/require"
 	"go.uber.org/goleak"
 
@@ -1714,63 +1712,6 @@ load 1ms
 	}
 }
 
-func TestRecoverEvaluatorRuntime(t *testing.T) {
-	var output []interface{}
-	logger := log.Logger(log.LoggerFunc(func(keyvals ...interface{}) error {
-		output = append(output, keyvals...)
-		return nil
-	}))
-	ev := &evaluator{logger: logger}
-
-	expr, _ := parser.ParseExpr("sum(up)")
-
-	var err error
-
-	defer func() {
-		require.EqualError(t, err, "unexpected error: runtime error: index out of range [123] with length 0")
-		require.Contains(t, output, "sum(up)")
-	}()
-	defer ev.recover(expr, nil, &err)
-
-	// Cause a runtime panic.
-	var a []int
-	a[123] = 1
-}
-
-func TestRecoverEvaluatorError(t *testing.T) {
-	ev := &evaluator{logger: log.NewNopLogger()}
-	var err error
-
-	e := errors.New("custom error")
-
-	defer func() {
-		require.EqualError(t, err, e.Error())
-	}()
-	defer ev.recover(nil, nil, &err)
-
-	panic(e)
-}
-
-func TestRecoverEvaluatorErrorWithWarnings(t *testing.T) {
-	ev := &evaluator{logger: log.NewNopLogger()}
-	var err error
-	var ws annotations.Annotations
-
-	warnings := annotations.New().Add(errors.New("custom warning"))
-	e := errWithWarnings{
-		err:      errors.New("custom error"),
-		warnings: warnings,
-	}
-
-	defer func() {
-		require.EqualError(t, err, e.Error())
-		require.Equal(t, warnings, ws, "wrong warning message")
-	}()
-	defer ev.recover(nil, &ws, &err)
-
-	panic(e)
-}
-
 func TestSubquerySelector(t *testing.T) {
 	type caseType struct {
 		Query  string

From 0dbfd20b695a8dfa0ddc23e76fda69b6ffcbc4bb Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Mon, 29 Apr 2024 13:14:18 +0100
Subject: [PATCH 12/13] test: move most PromQL tests into separate test package

So that they can import promqltest which imports promql.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/bench_test.go     |  13 +-
 promql/engine_test.go    | 569 ++++++++++++++++++++-------------------
 promql/functions_test.go |  11 +-
 promql/promql_test.go    |   9 +-
 promql/value_test.go     |  27 +-
 5 files changed, 331 insertions(+), 298 deletions(-)

diff --git a/promql/bench_test.go b/promql/bench_test.go
index 516b0d748..9a8529091 100644
--- a/promql/bench_test.go
+++ b/promql/bench_test.go
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package promql
+package promql_test
 
 import (
 	"context"
@@ -23,13 +23,14 @@ import (
 
 	"github.com/prometheus/prometheus/model/histogram"
 	"github.com/prometheus/prometheus/model/labels"
+	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/tsdbutil"
 	"github.com/prometheus/prometheus/util/teststorage"
 )
 
-func setupRangeQueryTestData(stor *teststorage.TestStorage, _ *Engine, interval, numIntervals int) error {
+func setupRangeQueryTestData(stor *teststorage.TestStorage, _ *promql.Engine, interval, numIntervals int) error {
 	ctx := context.Background()
 
 	metrics := []labels.Labels{}
@@ -249,13 +250,13 @@ func BenchmarkRangeQuery(b *testing.B) {
 	stor := teststorage.New(b)
 	stor.DB.DisableCompactions() // Don't want auto-compaction disrupting timings.
 	defer stor.Close()
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 50000000,
 		Timeout:    100 * time.Second,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 
 	const interval = 10000 // 10s interval.
 	// A day of data plus 10k steps.
@@ -324,7 +325,7 @@ func BenchmarkNativeHistograms(b *testing.B) {
 		},
 	}
 
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:               nil,
 		Reg:                  nil,
 		MaxSamples:           50000000,
@@ -338,7 +339,7 @@ func BenchmarkNativeHistograms(b *testing.B) {
 
 	for _, tc := range cases {
 		b.Run(tc.name, func(b *testing.B) {
-			ng := NewEngine(opts)
+			ng := promql.NewEngine(opts)
 			for i := 0; i < b.N; i++ {
 				qry, err := ng.NewRangeQuery(context.Background(), testStorage, nil, tc.query, start, end, step)
 				if err != nil {
diff --git a/promql/engine_test.go b/promql/engine_test.go
index 826531789..5ca110824 100644
--- a/promql/engine_test.go
+++ b/promql/engine_test.go
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package promql
+package promql_test
 
 import (
 	"context"
@@ -29,8 +29,10 @@ import (
 	"github.com/prometheus/prometheus/model/histogram"
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/model/timestamp"
+	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
 	"github.com/prometheus/prometheus/promql/parser/posrange"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/tsdbutil"
 	"github.com/prometheus/prometheus/util/almost"
@@ -40,6 +42,12 @@ import (
 	"github.com/prometheus/prometheus/util/testutil"
 )
 
+const (
+	env                  = "query execution"
+	defaultLookbackDelta = 5 * time.Minute
+	defaultEpsilon       = 0.000001 // Relative error allowed for sample values.
+)
+
 func TestMain(m *testing.M) {
 	goleak.VerifyTestMain(m)
 }
@@ -50,10 +58,10 @@ func TestQueryConcurrency(t *testing.T) {
 	dir, err := os.MkdirTemp("", "test_concurrency")
 	require.NoError(t, err)
 	defer os.RemoveAll(dir)
-	queryTracker := NewActiveQueryTracker(dir, maxConcurrency, nil)
+	queryTracker := promql.NewActiveQueryTracker(dir, maxConcurrency, nil)
 	t.Cleanup(queryTracker.Close)
 
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:             nil,
 		Reg:                nil,
 		MaxSamples:         10,
@@ -61,7 +69,7 @@ func TestQueryConcurrency(t *testing.T) {
 		ActiveQueryTracker: queryTracker,
 	}
 
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 	defer cancelCtx()
 
@@ -84,7 +92,7 @@ func TestQueryConcurrency(t *testing.T) {
 	}
 
 	for i := 0; i < maxConcurrency; i++ {
-		q := engine.newTestQuery(f)
+		q := engine.NewTestQuery(f)
 		go q.Exec(ctx)
 		select {
 		case <-processing:
@@ -94,7 +102,7 @@ func TestQueryConcurrency(t *testing.T) {
 		}
 	}
 
-	q := engine.newTestQuery(f)
+	q := engine.NewTestQuery(f)
 	go q.Exec(ctx)
 
 	select {
@@ -120,18 +128,33 @@ func TestQueryConcurrency(t *testing.T) {
 	}
 }
 
+// contextDone returns an error if the context was canceled or timed out.
+func contextDone(ctx context.Context, env string) error {
+	if err := ctx.Err(); err != nil {
+		switch {
+		case errors.Is(err, context.Canceled):
+			return promql.ErrQueryCanceled(env)
+		case errors.Is(err, context.DeadlineExceeded):
+			return promql.ErrQueryTimeout(env)
+		default:
+			return err
+		}
+	}
+	return nil
+}
+
 func TestQueryTimeout(t *testing.T) {
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 10,
 		Timeout:    5 * time.Millisecond,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 	defer cancelCtx()
 
-	query := engine.newTestQuery(func(ctx context.Context) error {
+	query := engine.NewTestQuery(func(ctx context.Context) error {
 		time.Sleep(100 * time.Millisecond)
 		return contextDone(ctx, "test statement execution")
 	})
@@ -139,20 +162,20 @@ func TestQueryTimeout(t *testing.T) {
 	res := query.Exec(ctx)
 	require.Error(t, res.Err, "expected timeout error but got none")
 
-	var e ErrQueryTimeout
+	var e promql.ErrQueryTimeout
 	require.ErrorAs(t, res.Err, &e, "expected timeout error but got: %s", res.Err)
 }
 
-const errQueryCanceled = ErrQueryCanceled("test statement execution")
+const errQueryCanceled = promql.ErrQueryCanceled("test statement execution")
 
 func TestQueryCancel(t *testing.T) {
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 	defer cancelCtx()
 
@@ -160,13 +183,13 @@ func TestQueryCancel(t *testing.T) {
 	block := make(chan struct{})
 	processing := make(chan struct{})
 
-	query1 := engine.newTestQuery(func(ctx context.Context) error {
+	query1 := engine.NewTestQuery(func(ctx context.Context) error {
 		processing <- struct{}{}
 		<-block
 		return contextDone(ctx, "test statement execution")
 	})
 
-	var res *Result
+	var res *promql.Result
 
 	go func() {
 		res = query1.Exec(ctx)
@@ -182,7 +205,7 @@ func TestQueryCancel(t *testing.T) {
 	require.Equal(t, errQueryCanceled, res.Err)
 
 	// Canceling a query before starting it must have no effect.
-	query2 := engine.newTestQuery(func(ctx context.Context) error {
+	query2 := engine.NewTestQuery(func(ctx context.Context) error {
 		return contextDone(ctx, "test statement execution")
 	})
 
@@ -220,14 +243,14 @@ func (e errSeriesSet) Err() error                        { return e.err }
 func (e errSeriesSet) Warnings() annotations.Annotations { return nil }
 
 func TestQueryError(t *testing.T) {
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := NewEngine(opts)
-	errStorage := ErrStorage{errors.New("storage error")}
+	engine := promql.NewEngine(opts)
+	errStorage := promql.ErrStorage{errors.New("storage error")}
 	queryable := storage.QueryableFunc(func(mint, maxt int64) (storage.Querier, error) {
 		return &errQuerier{err: errStorage}, nil
 	})
@@ -269,7 +292,7 @@ func (h *hintRecordingQuerier) Select(ctx context.Context, sortSeries bool, hint
 }
 
 func TestSelectHintsSetCorrectly(t *testing.T) {
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:           nil,
 		Reg:              nil,
 		MaxSamples:       10,
@@ -560,11 +583,11 @@ func TestSelectHintsSetCorrectly(t *testing.T) {
 		},
 	} {
 		t.Run(tc.query, func(t *testing.T) {
-			engine := NewEngine(opts)
+			engine := promql.NewEngine(opts)
 			hintsRecorder := &noopHintRecordingQueryable{}
 
 			var (
-				query Query
+				query promql.Query
 				err   error
 			)
 			ctx := context.Background()
@@ -585,13 +608,13 @@ func TestSelectHintsSetCorrectly(t *testing.T) {
 }
 
 func TestEngineShutdown(t *testing.T) {
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 
 	block := make(chan struct{})
@@ -604,13 +627,13 @@ func TestEngineShutdown(t *testing.T) {
 		<-block
 		return contextDone(ctx, "test statement execution")
 	}
-	query1 := engine.newTestQuery(f)
+	query1 := engine.NewTestQuery(f)
 
 	// Stopping the engine must cancel the base context. While executing queries is
 	// still possible, their context is canceled from the beginning and execution should
 	// terminate immediately.
 
-	var res *Result
+	var res *promql.Result
 	go func() {
 		res = query1.Exec(ctx)
 		processing <- struct{}{}
@@ -624,7 +647,7 @@ func TestEngineShutdown(t *testing.T) {
 	require.Error(t, res.Err, "expected error on shutdown during query but got none")
 	require.Equal(t, errQueryCanceled, res.Err)
 
-	query2 := engine.newTestQuery(func(context.Context) error {
+	query2 := engine.NewTestQuery(func(context.Context) error {
 		require.FailNow(t, "reached query execution unexpectedly")
 		return nil
 	})
@@ -634,12 +657,12 @@ func TestEngineShutdown(t *testing.T) {
 	res2 := query2.Exec(ctx)
 	require.Error(t, res2.Err, "expected error on querying with canceled context but got none")
 
-	var e ErrQueryCanceled
+	var e promql.ErrQueryCanceled
 	require.ErrorAs(t, res2.Err, &e, "expected cancellation error but got: %s", res2.Err)
 }
 
 func TestEngineEvalStmtTimestamps(t *testing.T) {
-	storage := LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 load 10s
   metric 1 2
 `)
@@ -656,13 +679,13 @@ load 10s
 		// Instant queries.
 		{
 			Query:  "1",
-			Result: Scalar{V: 1, T: 1000},
+			Result: promql.Scalar{V: 1, T: 1000},
 			Start:  time.Unix(1, 0),
 		},
 		{
 			Query: "metric",
-			Result: Vector{
-				Sample{
+			Result: promql.Vector{
+				promql.Sample{
 					F:      1,
 					T:      1000,
 					Metric: labels.FromStrings("__name__", "metric"),
@@ -672,9 +695,9 @@ load 10s
 		},
 		{
 			Query: "metric[20s]",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 1, T: 0}, {F: 2, T: 10000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 1, T: 0}, {F: 2, T: 10000}},
 					Metric: labels.FromStrings("__name__", "metric"),
 				},
 			},
@@ -683,9 +706,9 @@ load 10s
 		// Range queries.
 		{
 			Query: "1",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 1, T: 0}, {F: 1, T: 1000}, {F: 1, T: 2000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 1, T: 0}, {F: 1, T: 1000}, {F: 1, T: 2000}},
 					Metric: labels.EmptyLabels(),
 				},
 			},
@@ -695,9 +718,9 @@ load 10s
 		},
 		{
 			Query: "metric",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 1, T: 0}, {F: 1, T: 1000}, {F: 1, T: 2000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 1, T: 0}, {F: 1, T: 1000}, {F: 1, T: 2000}},
 					Metric: labels.FromStrings("__name__", "metric"),
 				},
 			},
@@ -707,9 +730,9 @@ load 10s
 		},
 		{
 			Query: "metric",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 1, T: 0}, {F: 1, T: 5000}, {F: 2, T: 10000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 1, T: 0}, {F: 1, T: 5000}, {F: 2, T: 10000}},
 					Metric: labels.FromStrings("__name__", "metric"),
 				},
 			},
@@ -726,7 +749,7 @@ load 10s
 	for i, c := range cases {
 		t.Run(fmt.Sprintf("%d query=%s", i, c.Query), func(t *testing.T) {
 			var err error
-			var qry Query
+			var qry promql.Query
 			engine := newTestEngine()
 			if c.Interval == 0 {
 				qry, err = engine.NewInstantQuery(context.Background(), storage, nil, c.Query, c.Start)
@@ -748,7 +771,7 @@ load 10s
 }
 
 func TestQueryStatistics(t *testing.T) {
-	storage := LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 load 10s
   metricWith1SampleEvery10Seconds 1+1x100
   metricWith3SampleEvery10Seconds{a="1",b="1"} 1+1x100
@@ -1271,12 +1294,12 @@ load 10s
 	origMaxSamples := engine.maxSamplesPerQuery
 	for _, c := range cases {
 		t.Run(c.Query, func(t *testing.T) {
-			opts := NewPrometheusQueryOpts(true, 0)
+			opts := promql.NewPrometheusQueryOpts(true, 0)
 			engine.maxSamplesPerQuery = origMaxSamples
 
 			runQuery := func(expErr error) *stats.Statistics {
 				var err error
-				var qry Query
+				var qry promql.Query
 				if c.Interval == 0 {
 					qry, err = engine.NewInstantQuery(context.Background(), storage, opts, c.Query, c.Start)
 				} else {
@@ -1300,13 +1323,13 @@ load 10s
 				return
 			}
 			engine.maxSamplesPerQuery = stats.Samples.PeakSamples - 1
-			runQuery(ErrTooManySamples(env))
+			runQuery(promql.ErrTooManySamples(env))
 		})
 	}
 }
 
 func TestMaxQuerySamples(t *testing.T) {
-	storage := LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 load 10s
   metric 1+1x100
   bigmetric{a="1"} 1+1x100
@@ -1422,7 +1445,7 @@ load 10s
 			Interval:   5 * time.Second,
 		},
 		{
-			// Sample as above but with only 1 part as step invariant.
+			// promql.Sample as above but with only 1 part as step invariant.
 			// Here the peak is caused by the non-step invariant part as it touches more time range.
 			// Hence at peak it is 2*21 (subquery from 0s to 20s)
 			//                     + 11 (buffer of a series per evaluation)
@@ -1455,7 +1478,7 @@ load 10s
 			engine := newTestEngine()
 			testFunc := func(expError error) {
 				var err error
-				var qry Query
+				var qry promql.Query
 				if c.Interval == 0 {
 					qry, err = engine.NewInstantQuery(context.Background(), storage, nil, c.Query, c.Start)
 				} else {
@@ -1478,14 +1501,14 @@ load 10s
 
 			// Exceeding limit.
 			engine.maxSamplesPerQuery = c.MaxSamples - 1
-			testFunc(ErrTooManySamples(env))
+			testFunc(promql.ErrTooManySamples(env))
 		})
 	}
 }
 
 func TestAtModifier(t *testing.T) {
 	engine := newTestEngine()
-	storage := LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 load 10s
   metric{job="1"} 0+1x1000
   metric{job="2"} 0+2x1000
@@ -1529,137 +1552,137 @@ load 1ms
 		{ // Time of the result is the evaluation time.
 			query: `metric_neg @ 0`,
 			start: 100,
-			result: Vector{
-				Sample{F: 1, T: 100000, Metric: lblsneg},
+			result: promql.Vector{
+				promql.Sample{F: 1, T: 100000, Metric: lblsneg},
 			},
 		}, {
 			query: `metric_neg @ -200`,
 			start: 100,
-			result: Vector{
-				Sample{F: 201, T: 100000, Metric: lblsneg},
+			result: promql.Vector{
+				promql.Sample{F: 201, T: 100000, Metric: lblsneg},
 			},
 		}, {
 			query: `metric{job="2"} @ 50`,
 			start: -2, end: 2, interval: 1,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 10, T: -2000}, {F: 10, T: -1000}, {F: 10, T: 0}, {F: 10, T: 1000}, {F: 10, T: 2000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 10, T: -2000}, {F: 10, T: -1000}, {F: 10, T: 0}, {F: 10, T: 1000}, {F: 10, T: 2000}},
 					Metric: lbls2,
 				},
 			},
 		}, { // Timestamps for matrix selector does not depend on the evaluation time.
 			query: "metric[20s] @ 300",
 			start: 10,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 28, T: 280000}, {F: 29, T: 290000}, {F: 30, T: 300000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 28, T: 280000}, {F: 29, T: 290000}, {F: 30, T: 300000}},
 					Metric: lbls1,
 				},
-				Series{
-					Floats: []FPoint{{F: 56, T: 280000}, {F: 58, T: 290000}, {F: 60, T: 300000}},
+				promql.Series{
+					Floats: []promql.FPoint{{F: 56, T: 280000}, {F: 58, T: 290000}, {F: 60, T: 300000}},
 					Metric: lbls2,
 				},
 			},
 		}, {
 			query: `metric_neg[2s] @ 0`,
 			start: 100,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 3, T: -2000}, {F: 2, T: -1000}, {F: 1, T: 0}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 3, T: -2000}, {F: 2, T: -1000}, {F: 1, T: 0}},
 					Metric: lblsneg,
 				},
 			},
 		}, {
 			query: `metric_neg[3s] @ -500`,
 			start: 100,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 504, T: -503000}, {F: 503, T: -502000}, {F: 502, T: -501000}, {F: 501, T: -500000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 504, T: -503000}, {F: 503, T: -502000}, {F: 502, T: -501000}, {F: 501, T: -500000}},
 					Metric: lblsneg,
 				},
 			},
 		}, {
 			query: `metric_ms[3ms] @ 2.345`,
 			start: 100,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 2342, T: 2342}, {F: 2343, T: 2343}, {F: 2344, T: 2344}, {F: 2345, T: 2345}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 2342, T: 2342}, {F: 2343, T: 2343}, {F: 2344, T: 2344}, {F: 2345, T: 2345}},
 					Metric: lblsms,
 				},
 			},
 		}, {
 			query: "metric[100s:25s] @ 300",
 			start: 100,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 20, T: 200000}, {F: 22, T: 225000}, {F: 25, T: 250000}, {F: 27, T: 275000}, {F: 30, T: 300000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 20, T: 200000}, {F: 22, T: 225000}, {F: 25, T: 250000}, {F: 27, T: 275000}, {F: 30, T: 300000}},
 					Metric: lbls1,
 				},
-				Series{
-					Floats: []FPoint{{F: 40, T: 200000}, {F: 44, T: 225000}, {F: 50, T: 250000}, {F: 54, T: 275000}, {F: 60, T: 300000}},
+				promql.Series{
+					Floats: []promql.FPoint{{F: 40, T: 200000}, {F: 44, T: 225000}, {F: 50, T: 250000}, {F: 54, T: 275000}, {F: 60, T: 300000}},
 					Metric: lbls2,
 				},
 			},
 		}, {
 			query: "metric_neg[50s:25s] @ 0",
 			start: 100,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 51, T: -50000}, {F: 26, T: -25000}, {F: 1, T: 0}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 51, T: -50000}, {F: 26, T: -25000}, {F: 1, T: 0}},
 					Metric: lblsneg,
 				},
 			},
 		}, {
 			query: "metric_neg[50s:25s] @ -100",
 			start: 100,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 151, T: -150000}, {F: 126, T: -125000}, {F: 101, T: -100000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 151, T: -150000}, {F: 126, T: -125000}, {F: 101, T: -100000}},
 					Metric: lblsneg,
 				},
 			},
 		}, {
 			query: `metric_ms[100ms:25ms] @ 2.345`,
 			start: 100,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 2250, T: 2250}, {F: 2275, T: 2275}, {F: 2300, T: 2300}, {F: 2325, T: 2325}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 2250, T: 2250}, {F: 2275, T: 2275}, {F: 2300, T: 2300}, {F: 2325, T: 2325}},
 					Metric: lblsms,
 				},
 			},
 		}, {
 			query: `metric_topk and topk(1, sum_over_time(metric_topk[50s] @ 100))`,
 			start: 50, end: 80, interval: 10,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 995, T: 50000}, {F: 994, T: 60000}, {F: 993, T: 70000}, {F: 992, T: 80000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 995, T: 50000}, {F: 994, T: 60000}, {F: 993, T: 70000}, {F: 992, T: 80000}},
 					Metric: lblstopk3,
 				},
 			},
 		}, {
 			query: `metric_topk and topk(1, sum_over_time(metric_topk[50s] @ 5000))`,
 			start: 50, end: 80, interval: 10,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 10, T: 50000}, {F: 12, T: 60000}, {F: 14, T: 70000}, {F: 16, T: 80000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 10, T: 50000}, {F: 12, T: 60000}, {F: 14, T: 70000}, {F: 16, T: 80000}},
 					Metric: lblstopk2,
 				},
 			},
 		}, {
 			query: `metric_topk and topk(1, sum_over_time(metric_topk[50s] @ end()))`,
 			start: 70, end: 100, interval: 10,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 993, T: 70000}, {F: 992, T: 80000}, {F: 991, T: 90000}, {F: 990, T: 100000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 993, T: 70000}, {F: 992, T: 80000}, {F: 991, T: 90000}, {F: 990, T: 100000}},
 					Metric: lblstopk3,
 				},
 			},
 		}, {
 			query: `metric_topk and topk(1, sum_over_time(metric_topk[50s] @ start()))`,
 			start: 100, end: 130, interval: 10,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 990, T: 100000}, {F: 989, T: 110000}, {F: 988, T: 120000}, {F: 987, T: 130000}},
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 990, T: 100000}, {F: 989, T: 110000}, {F: 988, T: 120000}, {F: 987, T: 130000}},
 					Metric: lblstopk3,
 				},
 			},
@@ -1668,9 +1691,9 @@ load 1ms
 			// The trick here is that the query range should be > lookback delta.
 			query: `timestamp(metric_timestamp @ 3600)`,
 			start: 0, end: 7 * 60, interval: 60,
-			result: Matrix{
-				Series{
-					Floats: []FPoint{
+			result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{
 						{F: 3600, T: 0},
 						{F: 3600, T: 60 * 1000},
 						{F: 3600, T: 2 * 60 * 1000},
@@ -1693,7 +1716,7 @@ load 1ms
 			}
 			start, end, interval := time.Unix(c.start, 0), time.Unix(c.end, 0), time.Duration(c.interval)*time.Second
 			var err error
-			var qry Query
+			var qry promql.Query
 			if c.end == 0 {
 				qry, err = engine.NewInstantQuery(context.Background(), storage, nil, c.query, start)
 			} else {
@@ -1703,9 +1726,9 @@ load 1ms
 
 			res := qry.Exec(context.Background())
 			require.NoError(t, res.Err)
-			if expMat, ok := c.result.(Matrix); ok {
+			if expMat, ok := c.result.(promql.Matrix); ok {
 				sort.Sort(expMat)
-				sort.Sort(res.Value.(Matrix))
+				sort.Sort(res.Value.(promql.Matrix))
 			}
 			testutil.RequireEqual(t, c.result, res.Value, "query %q failed", c.query)
 		})
@@ -1715,7 +1738,7 @@ load 1ms
 func TestSubquerySelector(t *testing.T) {
 	type caseType struct {
 		Query  string
-		Result Result
+		Result promql.Result
 		Start  time.Time
 	}
 
@@ -1729,11 +1752,11 @@ func TestSubquerySelector(t *testing.T) {
 			cases: []caseType{
 				{
 					Query: "metric[20s:10s]",
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 1, T: 0}, {F: 2, T: 10000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 1, T: 0}, {F: 2, T: 10000}},
 								Metric: labels.FromStrings("__name__", "metric"),
 							},
 						},
@@ -1743,11 +1766,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: "metric[20s:5s]",
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 1, T: 0}, {F: 1, T: 5000}, {F: 2, T: 10000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 1, T: 0}, {F: 1, T: 5000}, {F: 2, T: 10000}},
 								Metric: labels.FromStrings("__name__", "metric"),
 							},
 						},
@@ -1757,11 +1780,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: "metric[20s:5s] offset 2s",
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 1, T: 0}, {F: 1, T: 5000}, {F: 2, T: 10000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 1, T: 0}, {F: 1, T: 5000}, {F: 2, T: 10000}},
 								Metric: labels.FromStrings("__name__", "metric"),
 							},
 						},
@@ -1771,11 +1794,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: "metric[20s:5s] offset 6s",
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 1, T: 0}, {F: 1, T: 5000}, {F: 2, T: 10000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 1, T: 0}, {F: 1, T: 5000}, {F: 2, T: 10000}},
 								Metric: labels.FromStrings("__name__", "metric"),
 							},
 						},
@@ -1785,11 +1808,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: "metric[20s:5s] offset 4s",
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 2, T: 15000}, {F: 2, T: 20000}, {F: 2, T: 25000}, {F: 2, T: 30000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 2, T: 15000}, {F: 2, T: 20000}, {F: 2, T: 25000}, {F: 2, T: 30000}},
 								Metric: labels.FromStrings("__name__", "metric"),
 							},
 						},
@@ -1799,11 +1822,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: "metric[20s:5s] offset 5s",
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 2, T: 10000}, {F: 2, T: 15000}, {F: 2, T: 20000}, {F: 2, T: 25000}, {F: 2, T: 30000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 2, T: 10000}, {F: 2, T: 15000}, {F: 2, T: 20000}, {F: 2, T: 25000}, {F: 2, T: 30000}},
 								Metric: labels.FromStrings("__name__", "metric"),
 							},
 						},
@@ -1813,11 +1836,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: "metric[20s:5s] offset 6s",
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 2, T: 10000}, {F: 2, T: 15000}, {F: 2, T: 20000}, {F: 2, T: 25000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 2, T: 10000}, {F: 2, T: 15000}, {F: 2, T: 20000}, {F: 2, T: 25000}},
 								Metric: labels.FromStrings("__name__", "metric"),
 							},
 						},
@@ -1827,11 +1850,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: "metric[20s:5s] offset 7s",
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 2, T: 10000}, {F: 2, T: 15000}, {F: 2, T: 20000}, {F: 2, T: 25000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 2, T: 10000}, {F: 2, T: 15000}, {F: 2, T: 20000}, {F: 2, T: 25000}},
 								Metric: labels.FromStrings("__name__", "metric"),
 							},
 						},
@@ -1850,11 +1873,11 @@ func TestSubquerySelector(t *testing.T) {
 			cases: []caseType{
 				{ // Normal selector.
 					Query: `http_requests{group=~"pro.*",instance="0"}[30s:10s]`,
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 9990, T: 9990000}, {F: 10000, T: 10000000}, {F: 100, T: 10010000}, {F: 130, T: 10020000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 9990, T: 9990000}, {F: 10000, T: 10000000}, {F: 100, T: 10010000}, {F: 130, T: 10020000}},
 								Metric: labels.FromStrings("__name__", "http_requests", "job", "api-server", "instance", "0", "group", "production"),
 							},
 						},
@@ -1864,11 +1887,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{ // Default step.
 					Query: `http_requests{group=~"pro.*",instance="0"}[5m:]`,
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 9840, T: 9840000}, {F: 9900, T: 9900000}, {F: 9960, T: 9960000}, {F: 130, T: 10020000}, {F: 310, T: 10080000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 9840, T: 9840000}, {F: 9900, T: 9900000}, {F: 9960, T: 9960000}, {F: 130, T: 10020000}, {F: 310, T: 10080000}},
 								Metric: labels.FromStrings("__name__", "http_requests", "job", "api-server", "instance", "0", "group", "production"),
 							},
 						},
@@ -1878,11 +1901,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{ // Checking if high offset (>LookbackDelta) is being taken care of.
 					Query: `http_requests{group=~"pro.*",instance="0"}[5m:] offset 20m`,
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 8640, T: 8640000}, {F: 8700, T: 8700000}, {F: 8760, T: 8760000}, {F: 8820, T: 8820000}, {F: 8880, T: 8880000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 8640, T: 8640000}, {F: 8700, T: 8700000}, {F: 8760, T: 8760000}, {F: 8820, T: 8820000}, {F: 8880, T: 8880000}},
 								Metric: labels.FromStrings("__name__", "http_requests", "job", "api-server", "instance", "0", "group", "production"),
 							},
 						},
@@ -1892,23 +1915,23 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: `rate(http_requests[1m])[15s:5s]`,
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 3, T: 7985000}, {F: 3, T: 7990000}, {F: 3, T: 7995000}, {F: 3, T: 8000000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 3, T: 7985000}, {F: 3, T: 7990000}, {F: 3, T: 7995000}, {F: 3, T: 8000000}},
 								Metric: labels.FromStrings("job", "api-server", "instance", "0", "group", "canary"),
 							},
-							Series{
-								Floats: []FPoint{{F: 4, T: 7985000}, {F: 4, T: 7990000}, {F: 4, T: 7995000}, {F: 4, T: 8000000}},
+							promql.Series{
+								Floats: []promql.FPoint{{F: 4, T: 7985000}, {F: 4, T: 7990000}, {F: 4, T: 7995000}, {F: 4, T: 8000000}},
 								Metric: labels.FromStrings("job", "api-server", "instance", "1", "group", "canary"),
 							},
-							Series{
-								Floats: []FPoint{{F: 1, T: 7985000}, {F: 1, T: 7990000}, {F: 1, T: 7995000}, {F: 1, T: 8000000}},
+							promql.Series{
+								Floats: []promql.FPoint{{F: 1, T: 7985000}, {F: 1, T: 7990000}, {F: 1, T: 7995000}, {F: 1, T: 8000000}},
 								Metric: labels.FromStrings("job", "api-server", "instance", "0", "group", "production"),
 							},
-							Series{
-								Floats: []FPoint{{F: 2, T: 7985000}, {F: 2, T: 7990000}, {F: 2, T: 7995000}, {F: 2, T: 8000000}},
+							promql.Series{
+								Floats: []promql.FPoint{{F: 2, T: 7985000}, {F: 2, T: 7990000}, {F: 2, T: 7995000}, {F: 2, T: 8000000}},
 								Metric: labels.FromStrings("job", "api-server", "instance", "1", "group", "production"),
 							},
 						},
@@ -1918,11 +1941,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: `sum(http_requests{group=~"pro.*"})[30s:10s]`,
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 270, T: 90000}, {F: 300, T: 100000}, {F: 330, T: 110000}, {F: 360, T: 120000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 270, T: 90000}, {F: 300, T: 100000}, {F: 330, T: 110000}, {F: 360, T: 120000}},
 								Metric: labels.EmptyLabels(),
 							},
 						},
@@ -1932,11 +1955,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: `sum(http_requests)[40s:10s]`,
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 800, T: 80000}, {F: 900, T: 90000}, {F: 1000, T: 100000}, {F: 1100, T: 110000}, {F: 1200, T: 120000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 800, T: 80000}, {F: 900, T: 90000}, {F: 1000, T: 100000}, {F: 1100, T: 110000}, {F: 1200, T: 120000}},
 								Metric: labels.EmptyLabels(),
 							},
 						},
@@ -1946,11 +1969,11 @@ func TestSubquerySelector(t *testing.T) {
 				},
 				{
 					Query: `(sum(http_requests{group=~"p.*"})+sum(http_requests{group=~"c.*"}))[20s:5s]`,
-					Result: Result{
+					Result: promql.Result{
 						nil,
-						Matrix{
-							Series{
-								Floats: []FPoint{{F: 1000, T: 100000}, {F: 1000, T: 105000}, {F: 1100, T: 110000}, {F: 1100, T: 115000}, {F: 1200, T: 120000}},
+						promql.Matrix{
+							promql.Series{
+								Floats: []promql.FPoint{{F: 1000, T: 100000}, {F: 1000, T: 105000}, {F: 1100, T: 110000}, {F: 1100, T: 115000}, {F: 1200, T: 120000}},
 								Metric: labels.EmptyLabels(),
 							},
 						},
@@ -1963,7 +1986,7 @@ func TestSubquerySelector(t *testing.T) {
 	} {
 		t.Run("", func(t *testing.T) {
 			engine := newTestEngine()
-			storage := LoadedStorage(t, tst.loadString)
+			storage := promqltest.LoadedStorage(t, tst.loadString)
 			t.Cleanup(func() { storage.Close() })
 
 			for _, c := range tst.cases {
@@ -1973,7 +1996,7 @@ func TestSubquerySelector(t *testing.T) {
 
 					res := qry.Exec(context.Background())
 					require.Equal(t, c.Result.Err, res.Err)
-					mat := res.Value.(Matrix)
+					mat := res.Value.(promql.Matrix)
 					sort.Sort(mat)
 					testutil.RequireEqual(t, c.Result.Value, mat)
 				})
@@ -1984,7 +2007,7 @@ func TestSubquerySelector(t *testing.T) {
 
 func TestTimestampFunction_StepsMoreOftenThanSamples(t *testing.T) {
 	engine := newTestEngine()
-	storage := LoadedStorage(t, `
+	storage := promqltest.LoadedStorage(t, `
 load 1m
   metric 0+1x1000
 `)
@@ -1996,20 +2019,20 @@ load 1m
 	interval := time.Second
 
 	// We expect the value to be 0 for t=0s to t=59s (inclusive), then 60 for t=60s and t=61s.
-	expectedPoints := []FPoint{}
+	expectedPoints := []promql.FPoint{}
 
 	for t := 0; t <= 59; t++ {
-		expectedPoints = append(expectedPoints, FPoint{F: 0, T: int64(t * 1000)})
+		expectedPoints = append(expectedPoints, promql.FPoint{F: 0, T: int64(t * 1000)})
 	}
 
 	expectedPoints = append(
 		expectedPoints,
-		FPoint{F: 60, T: 60_000},
-		FPoint{F: 60, T: 61_000},
+		promql.FPoint{F: 60, T: 60_000},
+		promql.FPoint{F: 60, T: 61_000},
 	)
 
-	expectedResult := Matrix{
-		Series{
+	expectedResult := promql.Matrix{
+		promql.Series{
 			Floats: expectedPoints,
 			Metric: labels.EmptyLabels(),
 		},
@@ -2046,25 +2069,25 @@ func (f *FakeQueryLogger) Log(l ...interface{}) error {
 }
 
 func TestQueryLogger_basic(t *testing.T) {
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 
 	queryExec := func() {
 		ctx, cancelCtx := context.WithCancel(context.Background())
 		defer cancelCtx()
-		query := engine.newTestQuery(func(ctx context.Context) error {
+		query := engine.NewTestQuery(func(ctx context.Context) error {
 			return contextDone(ctx, "test statement execution")
 		})
 		res := query.Exec(ctx)
 		require.NoError(t, res.Err)
 	}
 
-	// Query works without query log initialized.
+	// promql.Query works without query log initialized.
 	queryExec()
 
 	f1 := NewFakeQueryLogger()
@@ -2097,21 +2120,21 @@ func TestQueryLogger_basic(t *testing.T) {
 }
 
 func TestQueryLogger_fields(t *testing.T) {
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 
 	f1 := NewFakeQueryLogger()
 	engine.SetQueryLogger(f1)
 
 	ctx, cancelCtx := context.WithCancel(context.Background())
-	ctx = NewOriginContext(ctx, map[string]interface{}{"foo": "bar"})
+	ctx = promql.NewOriginContext(ctx, map[string]interface{}{"foo": "bar"})
 	defer cancelCtx()
-	query := engine.newTestQuery(func(ctx context.Context) error {
+	query := engine.NewTestQuery(func(ctx context.Context) error {
 		return contextDone(ctx, "test statement execution")
 	})
 
@@ -2126,22 +2149,22 @@ func TestQueryLogger_fields(t *testing.T) {
 }
 
 func TestQueryLogger_error(t *testing.T) {
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 
 	f1 := NewFakeQueryLogger()
 	engine.SetQueryLogger(f1)
 
 	ctx, cancelCtx := context.WithCancel(context.Background())
-	ctx = NewOriginContext(ctx, map[string]interface{}{"foo": "bar"})
+	ctx = promql.NewOriginContext(ctx, map[string]interface{}{"foo": "bar"})
 	defer cancelCtx()
 	testErr := errors.New("failure")
-	query := engine.newTestQuery(func(ctx context.Context) error {
+	query := engine.NewTestQuery(func(ctx context.Context) error {
 		return testErr
 	})
 
@@ -2947,7 +2970,7 @@ func TestPreprocessAndWrapWithStepInvariantExpr(t *testing.T) {
 		t.Run(test.input, func(t *testing.T) {
 			expr, err := parser.ParseExpr(test.input)
 			require.NoError(t, err)
-			expr = PreprocessExpr(expr, startTime, endTime)
+			expr = promql.PreprocessExpr(expr, startTime, endTime)
 			if test.outputTest {
 				require.Equal(t, test.input, expr.String(), "error on input '%s'", test.input)
 			}
@@ -2958,64 +2981,64 @@ func TestPreprocessAndWrapWithStepInvariantExpr(t *testing.T) {
 
 func TestEngineOptsValidation(t *testing.T) {
 	cases := []struct {
-		opts     EngineOpts
+		opts     promql.EngineOpts
 		query    string
 		fail     bool
 		expError error
 	}{
 		{
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "metric @ 100", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "metric @ 100", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "rate(metric[1m] @ 100)", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "rate(metric[1m] @ 100)", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "rate(metric[1h:1m] @ 100)", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "rate(metric[1h:1m] @ 100)", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "metric @ start()", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "metric @ start()", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "rate(metric[1m] @ start())", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "rate(metric[1m] @ start())", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "rate(metric[1h:1m] @ start())", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "rate(metric[1h:1m] @ start())", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "metric @ end()", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "metric @ end()", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "rate(metric[1m] @ end())", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "rate(metric[1m] @ end())", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: false},
-			query: "rate(metric[1h:1m] @ end())", fail: true, expError: ErrValidationAtModifierDisabled,
+			opts:  promql.EngineOpts{EnableAtModifier: false},
+			query: "rate(metric[1h:1m] @ end())", fail: true, expError: promql.ErrValidationAtModifierDisabled,
 		}, {
-			opts:  EngineOpts{EnableAtModifier: true},
+			opts:  promql.EngineOpts{EnableAtModifier: true},
 			query: "metric @ 100",
 		}, {
-			opts:  EngineOpts{EnableAtModifier: true},
+			opts:  promql.EngineOpts{EnableAtModifier: true},
 			query: "rate(metric[1m] @ start())",
 		}, {
-			opts:  EngineOpts{EnableAtModifier: true},
+			opts:  promql.EngineOpts{EnableAtModifier: true},
 			query: "rate(metric[1h:1m] @ end())",
 		}, {
-			opts:  EngineOpts{EnableNegativeOffset: false},
-			query: "metric offset -1s", fail: true, expError: ErrValidationNegativeOffsetDisabled,
+			opts:  promql.EngineOpts{EnableNegativeOffset: false},
+			query: "metric offset -1s", fail: true, expError: promql.ErrValidationNegativeOffsetDisabled,
 		}, {
-			opts:  EngineOpts{EnableNegativeOffset: true},
+			opts:  promql.EngineOpts{EnableNegativeOffset: true},
 			query: "metric offset -1s",
 		}, {
-			opts:  EngineOpts{EnableAtModifier: true, EnableNegativeOffset: true},
+			opts:  promql.EngineOpts{EnableAtModifier: true, EnableNegativeOffset: true},
 			query: "metric @ 100 offset -2m",
 		}, {
-			opts:  EngineOpts{EnableAtModifier: true, EnableNegativeOffset: true},
+			opts:  promql.EngineOpts{EnableAtModifier: true, EnableNegativeOffset: true},
 			query: "metric offset -2m @ 100",
 		},
 	}
 
 	for _, c := range cases {
-		eng := NewEngine(c.opts)
+		eng := promql.NewEngine(c.opts)
 		_, err1 := eng.NewInstantQuery(context.Background(), nil, nil, c.query, time.Unix(10, 0))
 		_, err2 := eng.NewRangeQuery(context.Background(), nil, nil, c.query, time.Unix(0, 0), time.Unix(10, 0), time.Second)
 		if c.fail {
@@ -3043,9 +3066,9 @@ func TestRangeQuery(t *testing.T) {
 			Load: `load 30s
               bar 0 1 10 100 1000`,
 			Query: "sum_over_time(bar[30s])",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 0, T: 0}, {F: 11, T: 60000}, {F: 1100, T: 120000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 0, T: 0}, {F: 11, T: 60000}, {F: 1100, T: 120000}},
 					Metric: labels.EmptyLabels(),
 				},
 			},
@@ -3058,9 +3081,9 @@ func TestRangeQuery(t *testing.T) {
 			Load: `load 30s
               bar 0 1 10 100 1000 0 0 0 0`,
 			Query: "sum_over_time(bar[30s])",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 0, T: 0}, {F: 11, T: 60000}, {F: 1100, T: 120000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 0, T: 0}, {F: 11, T: 60000}, {F: 1100, T: 120000}},
 					Metric: labels.EmptyLabels(),
 				},
 			},
@@ -3073,9 +3096,9 @@ func TestRangeQuery(t *testing.T) {
 			Load: `load 30s
               bar 0 1 10 100 1000 10000 100000 1000000 10000000`,
 			Query: "sum_over_time(bar[30s])",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 0, T: 0}, {F: 11, T: 60000}, {F: 1100, T: 120000}, {F: 110000, T: 180000}, {F: 11000000, T: 240000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 0, T: 0}, {F: 11, T: 60000}, {F: 1100, T: 120000}, {F: 110000, T: 180000}, {F: 11000000, T: 240000}},
 					Metric: labels.EmptyLabels(),
 				},
 			},
@@ -3088,9 +3111,9 @@ func TestRangeQuery(t *testing.T) {
 			Load: `load 30s
               bar 5 17 42 2 7 905 51`,
 			Query: "sum_over_time(bar[30s])",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 5, T: 0}, {F: 59, T: 60000}, {F: 9, T: 120000}, {F: 956, T: 180000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 5, T: 0}, {F: 59, T: 60000}, {F: 9, T: 120000}, {F: 956, T: 180000}},
 					Metric: labels.EmptyLabels(),
 				},
 			},
@@ -3103,9 +3126,9 @@ func TestRangeQuery(t *testing.T) {
 			Load: `load 30s
               metric 1+1x4`,
 			Query: "metric",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 1, T: 0}, {F: 3, T: 60000}, {F: 5, T: 120000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 1, T: 0}, {F: 3, T: 60000}, {F: 5, T: 120000}},
 					Metric: labels.FromStrings("__name__", "metric"),
 				},
 			},
@@ -3118,9 +3141,9 @@ func TestRangeQuery(t *testing.T) {
 			Load: `load 30s
               metric 1+1x8`,
 			Query: "metric",
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 1, T: 0}, {F: 3, T: 60000}, {F: 5, T: 120000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 1, T: 0}, {F: 3, T: 60000}, {F: 5, T: 120000}},
 					Metric: labels.FromStrings("__name__", "metric"),
 				},
 			},
@@ -3134,16 +3157,16 @@ func TestRangeQuery(t *testing.T) {
 							foo{job="1"} 1+1x4
 							bar{job="2"} 1+1x4`,
 			Query: `foo > 2 or bar`,
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 1, T: 0}, {F: 3, T: 60000}, {F: 5, T: 120000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 1, T: 0}, {F: 3, T: 60000}, {F: 5, T: 120000}},
 					Metric: labels.FromStrings(
 						"__name__", "bar",
 						"job", "2",
 					),
 				},
-				Series{
-					Floats: []FPoint{{F: 3, T: 60000}, {F: 5, T: 120000}},
+				promql.Series{
+					Floats: []promql.FPoint{{F: 3, T: 60000}, {F: 5, T: 120000}},
 					Metric: labels.FromStrings(
 						"__name__", "foo",
 						"job", "1",
@@ -3159,9 +3182,9 @@ func TestRangeQuery(t *testing.T) {
 			Load: `load 30s
 							requests{job="1", __address__="bar"} 100`,
 			Query: `requests * 2`,
-			Result: Matrix{
-				Series{
-					Floats: []FPoint{{F: 200, T: 0}, {F: 200, T: 60000}, {F: 200, T: 120000}},
+			Result: promql.Matrix{
+				promql.Series{
+					Floats: []promql.FPoint{{F: 200, T: 0}, {F: 200, T: 60000}, {F: 200, T: 120000}},
 					Metric: labels.FromStrings(
 						"__address__", "bar",
 						"job", "1",
@@ -3176,7 +3199,7 @@ func TestRangeQuery(t *testing.T) {
 	for _, c := range cases {
 		t.Run(c.Name, func(t *testing.T) {
 			engine := newTestEngine()
-			storage := LoadedStorage(t, c.Load)
+			storage := promqltest.LoadedStorage(t, c.Load)
 			t.Cleanup(func() { storage.Close() })
 
 			qry, err := engine.NewRangeQuery(context.Background(), storage, nil, c.Query, c.Start, c.End, c.Interval)
@@ -3244,7 +3267,7 @@ func TestNativeHistogramRate(t *testing.T) {
 		require.Len(t, matrix, 1)
 		require.Len(t, matrix[0].Histograms, 2)
 		actualHistograms := matrix[0].Histograms
-		expectedHistograms := []HPoint{{
+		expectedHistograms := []promql.HPoint{{
 			T: 300000,
 			H: &histogram.FloatHistogram{
 				CounterResetHint: histogram.GaugeType,
@@ -4408,7 +4431,7 @@ func TestNativeHistogram_Sum_Count_Add_AvgOperator(t *testing.T) {
 				}
 				require.NoError(t, app.Commit())
 
-				queryAndCheck := func(queryString string, ts int64, exp Vector) {
+				queryAndCheck := func(queryString string, ts int64, exp promql.Vector) {
 					qry, err := engine.NewInstantQuery(context.Background(), storage, nil, queryString, timestamp.Time(ts))
 					require.NoError(t, err)
 
@@ -4432,7 +4455,7 @@ func TestNativeHistogram_Sum_Count_Add_AvgOperator(t *testing.T) {
 
 				// sum().
 				queryString := fmt.Sprintf("sum(%s)", seriesName)
-				queryAndCheck(queryString, ts, []Sample{{T: ts, H: &c.expected, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, ts, []promql.Sample{{T: ts, H: &c.expected, Metric: labels.EmptyLabels()}})
 
 				queryString = `sum({idx="0"})`
 				var annos annotations.Annotations
@@ -4444,26 +4467,26 @@ func TestNativeHistogram_Sum_Count_Add_AvgOperator(t *testing.T) {
 				for idx := 1; idx < len(c.histograms); idx++ {
 					queryString += fmt.Sprintf(` + ignoring(idx) %s{idx="%d"}`, seriesName, idx)
 				}
-				queryAndCheck(queryString, ts, []Sample{{T: ts, H: &c.expected, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, ts, []promql.Sample{{T: ts, H: &c.expected, Metric: labels.EmptyLabels()}})
 
 				// count().
 				queryString = fmt.Sprintf("count(%s)", seriesName)
-				queryAndCheck(queryString, ts, []Sample{{T: ts, F: 4, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, ts, []promql.Sample{{T: ts, F: 4, Metric: labels.EmptyLabels()}})
 
 				// avg().
 				queryString = fmt.Sprintf("avg(%s)", seriesName)
-				queryAndCheck(queryString, ts, []Sample{{T: ts, H: &c.expectedAvg, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, ts, []promql.Sample{{T: ts, H: &c.expectedAvg, Metric: labels.EmptyLabels()}})
 
 				offset := int64(len(c.histograms) - 1)
 				newTs := ts + offset*int64(time.Minute/time.Millisecond)
 
 				// sum_over_time().
 				queryString = fmt.Sprintf("sum_over_time(%s[%dm:1m])", seriesNameOverTime, offset)
-				queryAndCheck(queryString, newTs, []Sample{{T: newTs, H: &c.expected, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, newTs, []promql.Sample{{T: newTs, H: &c.expected, Metric: labels.EmptyLabels()}})
 
 				// avg_over_time().
 				queryString = fmt.Sprintf("avg_over_time(%s[%dm:1m])", seriesNameOverTime, offset)
-				queryAndCheck(queryString, newTs, []Sample{{T: newTs, H: &c.expectedAvg, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, newTs, []promql.Sample{{T: newTs, H: &c.expectedAvg, Metric: labels.EmptyLabels()}})
 			})
 			idx0++
 		}
@@ -4670,7 +4693,7 @@ func TestNativeHistogram_SubOperator(t *testing.T) {
 				}
 				require.NoError(t, app.Commit())
 
-				queryAndCheck := func(queryString string, exp Vector) {
+				queryAndCheck := func(queryString string, exp promql.Vector) {
 					qry, err := engine.NewInstantQuery(context.Background(), storage, nil, queryString, timestamp.Time(ts))
 					require.NoError(t, err)
 
@@ -4698,7 +4721,7 @@ func TestNativeHistogram_SubOperator(t *testing.T) {
 				for idx := 1; idx < len(c.histograms); idx++ {
 					queryString += fmt.Sprintf(` - ignoring(idx) %s{idx="%d"}`, seriesName, idx)
 				}
-				queryAndCheck(queryString, []Sample{{T: ts, H: &c.expected, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expected, Metric: labels.EmptyLabels()}})
 			})
 		}
 		idx0++
@@ -4828,7 +4851,7 @@ func TestNativeHistogram_MulDivOperator(t *testing.T) {
 				require.NoError(t, err)
 				require.NoError(t, app.Commit())
 
-				queryAndCheck := func(queryString string, exp Vector) {
+				queryAndCheck := func(queryString string, exp promql.Vector) {
 					qry, err := engine.NewInstantQuery(context.Background(), storage, nil, queryString, timestamp.Time(ts))
 					require.NoError(t, err)
 
@@ -4843,27 +4866,27 @@ func TestNativeHistogram_MulDivOperator(t *testing.T) {
 
 				// histogram * scalar.
 				queryString := fmt.Sprintf(`%s * %f`, seriesName, c.scalar)
-				queryAndCheck(queryString, []Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
 
 				// scalar * histogram.
 				queryString = fmt.Sprintf(`%f * %s`, c.scalar, seriesName)
-				queryAndCheck(queryString, []Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
 
 				// histogram * float.
 				queryString = fmt.Sprintf(`%s * %s`, seriesName, floatSeriesName)
-				queryAndCheck(queryString, []Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
 
 				// float * histogram.
 				queryString = fmt.Sprintf(`%s * %s`, floatSeriesName, seriesName)
-				queryAndCheck(queryString, []Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
 
 				// histogram / scalar.
 				queryString = fmt.Sprintf(`%s / %f`, seriesName, c.scalar)
-				queryAndCheck(queryString, []Sample{{T: ts, H: &c.expectedDiv, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedDiv, Metric: labels.EmptyLabels()}})
 
 				// histogram / float.
 				queryString = fmt.Sprintf(`%s / %s`, seriesName, floatSeriesName)
-				queryAndCheck(queryString, []Sample{{T: ts, H: &c.expectedDiv, Metric: labels.EmptyLabels()}})
+				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedDiv, Metric: labels.EmptyLabels()}})
 			})
 			idx0++
 		}
@@ -4934,7 +4957,7 @@ metric 0 1 2
 		c := c
 		t.Run(c.name, func(t *testing.T) {
 			engine := newTestEngine()
-			storage := LoadedStorage(t, load)
+			storage := promqltest.LoadedStorage(t, load)
 			t.Cleanup(func() { storage.Close() })
 
 			if c.engineLookback != 0 {
@@ -4946,7 +4969,7 @@ metric 0 1 2
 
 			res := qry.Exec(context.Background())
 			require.NoError(t, res.Err)
-			vec, ok := res.Value.(Vector)
+			vec, ok := res.Value.(promql.Vector)
 			require.True(t, ok)
 			if c.expectSamples {
 				require.NotEmpty(t, vec)
@@ -4956,3 +4979,9 @@ metric 0 1 2
 		})
 	}
 }
+
+func makeInt64Pointer(val int64) *int64 {
+	valp := new(int64)
+	*valp = val
+	return valp
+}
diff --git a/promql/functions_test.go b/promql/functions_test.go
index 08e4900f5..aef59c837 100644
--- a/promql/functions_test.go
+++ b/promql/functions_test.go
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package promql
+package promql_test
 
 import (
 	"context"
@@ -22,6 +22,7 @@ import (
 
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/model/timestamp"
+	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
 	"github.com/prometheus/prometheus/util/teststorage"
 )
@@ -32,13 +33,13 @@ func TestDeriv(t *testing.T) {
 	// so we test it by hand.
 	storage := teststorage.New(t)
 	defer storage.Close()
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 10000,
 		Timeout:    10 * time.Second,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 
 	a := storage.Appender(context.Background())
 
@@ -69,13 +70,13 @@ func TestDeriv(t *testing.T) {
 
 func TestFunctionList(t *testing.T) {
 	// Test that Functions and parser.Functions list the same functions.
-	for i := range FunctionCalls {
+	for i := range promql.FunctionCalls {
 		_, ok := parser.Functions[i]
 		require.True(t, ok, "function %s exists in promql package, but not in parser package", i)
 	}
 
 	for i := range parser.Functions {
-		_, ok := FunctionCalls[i]
+		_, ok := promql.FunctionCalls[i]
 		require.True(t, ok, "function %s exists in parser package, but not in promql package", i)
 	}
 }
diff --git a/promql/promql_test.go b/promql/promql_test.go
index 87ec2cd4e..59ec4756e 100644
--- a/promql/promql_test.go
+++ b/promql/promql_test.go
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package promql
+package promql_test
 
 import (
 	"context"
@@ -22,11 +22,12 @@ import (
 	"github.com/stretchr/testify/require"
 	"golang.org/x/sync/errgroup"
 
+	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/util/teststorage"
 )
 
-func newTestEngine() *Engine {
+func newTestEngine() *promql.Engine {
 	return promqltest.NewTestEngine(false, 0, promqltest.DefaultMaxSamplesPerQuery)
 }
 
@@ -38,13 +39,13 @@ func TestEvaluations(t *testing.T) {
 func TestConcurrentRangeQueries(t *testing.T) {
 	stor := teststorage.New(t)
 	defer stor.Close()
-	opts := EngineOpts{
+	opts := promql.EngineOpts{
 		Logger:     nil,
 		Reg:        nil,
 		MaxSamples: 50000000,
 		Timeout:    100 * time.Second,
 	}
-	engine := NewEngine(opts)
+	engine := promql.NewEngine(opts)
 
 	const interval = 10000 // 10s interval.
 	// A day of data plus 10k steps.
diff --git a/promql/value_test.go b/promql/value_test.go
index c93ba8213..0017b41e2 100644
--- a/promql/value_test.go
+++ b/promql/value_test.go
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package promql
+package promql_test
 
 import (
 	"testing"
@@ -19,39 +19,40 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/prometheus/prometheus/model/labels"
+	"github.com/prometheus/prometheus/promql"
 )
 
 func TestVector_ContainsSameLabelset(t *testing.T) {
 	for name, tc := range map[string]struct {
-		vector   Vector
+		vector   promql.Vector
 		expected bool
 	}{
 		"empty vector": {
-			vector:   Vector{},
+			vector:   promql.Vector{},
 			expected: false,
 		},
 		"vector with one series": {
-			vector: Vector{
+			vector: promql.Vector{
 				{Metric: labels.FromStrings("lbl", "a")},
 			},
 			expected: false,
 		},
 		"vector with two different series": {
-			vector: Vector{
+			vector: promql.Vector{
 				{Metric: labels.FromStrings("lbl", "a")},
 				{Metric: labels.FromStrings("lbl", "b")},
 			},
 			expected: false,
 		},
 		"vector with two equal series": {
-			vector: Vector{
+			vector: promql.Vector{
 				{Metric: labels.FromStrings("lbl", "a")},
 				{Metric: labels.FromStrings("lbl", "a")},
 			},
 			expected: true,
 		},
 		"vector with three series, two equal": {
-			vector: Vector{
+			vector: promql.Vector{
 				{Metric: labels.FromStrings("lbl", "a")},
 				{Metric: labels.FromStrings("lbl", "b")},
 				{Metric: labels.FromStrings("lbl", "a")},
@@ -67,35 +68,35 @@ func TestVector_ContainsSameLabelset(t *testing.T) {
 
 func TestMatrix_ContainsSameLabelset(t *testing.T) {
 	for name, tc := range map[string]struct {
-		matrix   Matrix
+		matrix   promql.Matrix
 		expected bool
 	}{
 		"empty matrix": {
-			matrix:   Matrix{},
+			matrix:   promql.Matrix{},
 			expected: false,
 		},
 		"matrix with one series": {
-			matrix: Matrix{
+			matrix: promql.Matrix{
 				{Metric: labels.FromStrings("lbl", "a")},
 			},
 			expected: false,
 		},
 		"matrix with two different series": {
-			matrix: Matrix{
+			matrix: promql.Matrix{
 				{Metric: labels.FromStrings("lbl", "a")},
 				{Metric: labels.FromStrings("lbl", "b")},
 			},
 			expected: false,
 		},
 		"matrix with two equal series": {
-			matrix: Matrix{
+			matrix: promql.Matrix{
 				{Metric: labels.FromStrings("lbl", "a")},
 				{Metric: labels.FromStrings("lbl", "a")},
 			},
 			expected: true,
 		},
 		"matrix with three series, two equal": {
-			matrix: Matrix{
+			matrix: promql.Matrix{
 				{Metric: labels.FromStrings("lbl", "a")},
 				{Metric: labels.FromStrings("lbl", "b")},
 				{Metric: labels.FromStrings("lbl", "a")},

From 786e0e706cc90cb54f59f0c95704473a963f995f Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Sat, 4 May 2024 14:05:11 +0100
Subject: [PATCH 13/13] test: PromQL: stop using internal fields of engine

* set enablePerStepStats and lookback duration via
  `NewTestEngine` parameters.
* check maxSamples by recreating query engine
* check lookback without modifying internals

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---
 promql/engine_test.go     | 16 +++++-----------
 promql/promql_test.go     |  2 +-
 promql/promqltest/test.go |  2 +-
 3 files changed, 7 insertions(+), 13 deletions(-)

diff --git a/promql/engine_test.go b/promql/engine_test.go
index 5ca110824..59e707011 100644
--- a/promql/engine_test.go
+++ b/promql/engine_test.go
@@ -1289,13 +1289,10 @@ load 10s
 		},
 	}
 
-	engine := newTestEngine()
-	engine.enablePerStepStats = true
-	origMaxSamples := engine.maxSamplesPerQuery
 	for _, c := range cases {
 		t.Run(c.Query, func(t *testing.T) {
 			opts := promql.NewPrometheusQueryOpts(true, 0)
-			engine.maxSamplesPerQuery = origMaxSamples
+			engine := promqltest.NewTestEngine(true, 0, promqltest.DefaultMaxSamplesPerQuery)
 
 			runQuery := func(expErr error) *stats.Statistics {
 				var err error
@@ -1322,7 +1319,7 @@ load 10s
 			if c.SkipMaxCheck {
 				return
 			}
-			engine.maxSamplesPerQuery = stats.Samples.PeakSamples - 1
+			engine = promqltest.NewTestEngine(true, 0, stats.Samples.PeakSamples-1)
 			runQuery(promql.ErrTooManySamples(env))
 		})
 	}
@@ -1496,11 +1493,11 @@ load 10s
 			}
 
 			// Within limit.
-			engine.maxSamplesPerQuery = c.MaxSamples
+			engine = promqltest.NewTestEngine(false, 0, c.MaxSamples)
 			testFunc(nil)
 
 			// Exceeding limit.
-			engine.maxSamplesPerQuery = c.MaxSamples - 1
+			engine = promqltest.NewTestEngine(false, 0, c.MaxSamples-1)
 			testFunc(promql.ErrTooManySamples(env))
 		})
 	}
@@ -4956,13 +4953,10 @@ metric 0 1 2
 	for _, c := range cases {
 		c := c
 		t.Run(c.name, func(t *testing.T) {
-			engine := newTestEngine()
+			engine := promqltest.NewTestEngine(false, c.engineLookback, promqltest.DefaultMaxSamplesPerQuery)
 			storage := promqltest.LoadedStorage(t, load)
 			t.Cleanup(func() { storage.Close() })
 
-			if c.engineLookback != 0 {
-				engine.lookbackDelta = c.engineLookback
-			}
 			opts := promql.NewPrometheusQueryOpts(false, c.queryLookback)
 			qry, err := engine.NewInstantQuery(context.Background(), storage, opts, query, c.ts)
 			require.NoError(t, err)
diff --git a/promql/promql_test.go b/promql/promql_test.go
index 59ec4756e..7bafc02e3 100644
--- a/promql/promql_test.go
+++ b/promql/promql_test.go
@@ -32,7 +32,7 @@ func newTestEngine() *promql.Engine {
 }
 
 func TestEvaluations(t *testing.T) {
-	RunBuiltinTests(t, newTestEngine())
+	promqltest.RunBuiltinTests(t, newTestEngine())
 }
 
 // Run a lot of queries at the same time, to check for race conditions.
diff --git a/promql/promqltest/test.go b/promql/promqltest/test.go
index 1b2ce78af..1affd91f6 100644
--- a/promql/promqltest/test.go
+++ b/promql/promqltest/test.go
@@ -76,7 +76,7 @@ func NewTestEngine(enablePerStepStats bool, lookbackDelta time.Duration, maxSamp
 	return promql.NewEngine(promql.EngineOpts{
 		Logger:                   nil,
 		Reg:                      nil,
-		MaxSamples:               DefaultMaxSamplesPerQuery,
+		MaxSamples:               maxSamples,
 		Timeout:                  100 * time.Second,
 		NoStepSubqueryIntervalFn: func(int64) int64 { return durationMilliseconds(1 * time.Minute) },
 		EnableAtModifier:         true,