prometheus/web/ui/module/codemirror-promql/src/parser/path-finder.ts
Augustin Husson 29b788a7b5 remove app package in codemirror-module
Signed-off-by: Augustin Husson <husson.augustin@gmail.com>
2021-09-09 17:52:03 +02:00

101 lines
3.5 KiB
TypeScript

// Copyright 2021 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.
import { SyntaxNode } from 'lezer-tree';
// walkBackward will iterate other the tree from the leaf to the root until it founds the given `exit` node.
// It returns null if the exit is not found.
export function walkBackward(node: SyntaxNode, exit: number): SyntaxNode | null {
const cursor = node.cursor;
let cursorIsMoving = true;
while (cursorIsMoving && cursor.type.id !== exit) {
cursorIsMoving = cursor.parent();
}
return cursor.type.id === exit ? cursor.node : null;
}
// walkThrough is going to follow the path passed in parameter.
// If it succeeds to reach the last id/name of the path, then it will return the corresponding Subtree.
// Otherwise if it's not possible to reach the last id/name of the path, it will return `null`
// Note: the way followed during the iteration of the tree to find the given path, is only from the root to the leaf.
export function walkThrough(node: SyntaxNode, ...path: (number | string)[]): SyntaxNode | null {
const cursor = node.cursor;
let i = 0;
let cursorIsMoving = true;
path.unshift(cursor.type.id);
while (i < path.length && cursorIsMoving) {
if (cursor.type.id === path[i] || cursor.type.name === path[i]) {
i++;
if (i < path.length) {
cursorIsMoving = cursor.next();
}
} else {
cursorIsMoving = cursor.nextSibling();
}
}
if (i >= path.length) {
return cursor.node;
}
return null;
}
export function containsAtLeastOneChild(node: SyntaxNode, ...child: (number | string)[]): boolean {
const cursor = node.cursor;
if (!cursor.next()) {
// let's try to move directly to the children level and
// return false immediately if the current node doesn't have any child
return false;
}
let result = false;
do {
result = child.some((n) => cursor.type.id === n || cursor.type.name === n);
} while (!result && cursor.nextSibling());
return result;
}
export function containsChild(node: SyntaxNode, ...child: (number | string)[]): boolean {
const cursor = node.cursor;
if (!cursor.next()) {
// let's try to move directly to the children level and
// return false immediately if the current node doesn't have any child
return false;
}
let i = 0;
do {
if (cursor.type.id === child[i] || cursor.type.name === child[i]) {
i++;
}
} while (i < child.length && cursor.nextSibling());
return i >= child.length;
}
export function retrieveAllRecursiveNodes(parentNode: SyntaxNode | null, recursiveNode: number, leaf: number): SyntaxNode[] {
const nodes: SyntaxNode[] = [];
function recursiveRetrieveNode(node: SyntaxNode | null, nodes: SyntaxNode[]) {
const subNode = node?.getChild(recursiveNode);
const le = node?.lastChild;
if (subNode && subNode.type.id === recursiveNode) {
recursiveRetrieveNode(subNode, nodes);
}
if (le && le.type.id === leaf) {
nodes.push(le);
}
}
recursiveRetrieveNode(parentNode, nodes);
return nodes;
}