fix: lock around shared map write

src/environment.go

@@ -10,6 +10,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/distatus/battery"
@@ -65,11 +66,15 @@ type environmentInfo interface {
 }
 
 type environment struct {
-	args     *args
+	args *args
-	cwd      string
+	cwd  string
-	commands map[string]string
 }
 
+var (
+	commands map[string]string = make(map[string]string)
+	lock                       = sync.Mutex{}
+)
+
 func (env *environment) getenv(key string) string {
 	return os.Getenv(key)
 }
@@ -160,7 +165,7 @@ func (env *environment) getPlatform() string {
 }
 
 func (env *environment) runCommand(command string, args ...string) (string, error) {
-	if cmd, ok := env.commands[command]; ok {
+	if cmd, ok := commands[command]; ok {
 		command = cmd
 	}
 	out, err := exec.Command(command, args...).Output()
@@ -176,12 +181,14 @@ func (env *environment) runShellCommand(shell, command string) string {
 }
 
 func (env *environment) hasCommand(command string) bool {
-	if _, ok := env.commands[command]; ok {
+	if _, ok := commands[command]; ok {
 		return true
 	}
 	path, err := exec.LookPath(command)
 	if err == nil {
-		env.commands[command] = path
+		lock.Lock()
+		commands[command] = path
+		lock.Unlock()
 		return true
 	}
 	return false

src/main.go

@@ -101,8 +101,7 @@ func main() {
 	}
 	flag.Parse()
 	env := &environment{
-		args:     args,
+		args: args,
-		commands: make(map[string]string),
 	}
 	if *args.Millis {
 		fmt.Print(time.Now().UnixNano() / 1000000)

src/segment_command_test.go

@@ -7,9 +7,7 @@ import (
 )
 
 func TestExecuteCommand(t *testing.T) {
-	env := &environment{
+	env := &environment{}
-		commands: make(map[string]string),
-	}
 	props := &properties{
 		values: map[Property]interface{}{
 			Command: "echo hello",
@@ -25,9 +23,7 @@ func TestExecuteCommand(t *testing.T) {
 }
 
 func TestExecuteMultipleCommandsOrFirst(t *testing.T) {
-	env := &environment{
+	env := &environment{}
-		commands: make(map[string]string),
-	}
 	props := &properties{
 		values: map[Property]interface{}{
 			Command: "exit 1 || echo hello",
@@ -43,9 +39,7 @@ func TestExecuteMultipleCommandsOrFirst(t *testing.T) {
 }
 
 func TestExecuteMultipleCommandsOrSecond(t *testing.T) {
-	env := &environment{
+	env := &environment{}
-		commands: make(map[string]string),
-	}
 	props := &properties{
 		values: map[Property]interface{}{
 			Command: "echo hello || echo world",
@@ -61,9 +55,7 @@ func TestExecuteMultipleCommandsOrSecond(t *testing.T) {
 }
 
 func TestExecuteMultipleCommandsAnd(t *testing.T) {
-	env := &environment{
+	env := &environment{}
-		commands: make(map[string]string),
-	}
 	props := &properties{
 		values: map[Property]interface{}{
 			Command: "echo hello && echo world",
@@ -79,9 +71,7 @@ func TestExecuteMultipleCommandsAnd(t *testing.T) {
 }
 
 func TestExecuteSingleCommandEmpty(t *testing.T) {
-	env := &environment{
+	env := &environment{}
-		commands: make(map[string]string),
-	}
 	props := &properties{
 		values: map[Property]interface{}{
 			Command: "",
@@ -96,9 +86,7 @@ func TestExecuteSingleCommandEmpty(t *testing.T) {
 }
 
 func TestExecuteSingleCommandNoCommandProperty(t *testing.T) {
-	env := &environment{
+	env := &environment{}
-		commands: make(map[string]string),
-	}
 	props := &properties{}
 	c := &command{
 		props: props,
@@ -110,9 +98,7 @@ func TestExecuteSingleCommandNoCommandProperty(t *testing.T) {
 }
 
 func TestExecuteMultipleCommandsAndDisabled(t *testing.T) {
-	env := &environment{
+	env := &environment{}
-		commands: make(map[string]string),
-	}
 	props := &properties{
 		values: map[Property]interface{}{
 			Command: "echo && echo",
@@ -127,9 +113,7 @@ func TestExecuteMultipleCommandsAndDisabled(t *testing.T) {
 }
 
 func TestExecuteMultipleCommandsOrDisabled(t *testing.T) {
-	env := &environment{
+	env := &environment{}
-		commands: make(map[string]string),
-	}
 	props := &properties{
 		values: map[Property]interface{}{
 			Command: "echo|| echo",