all: make use of some more Go 1.22 std APIs

I was reminded that I had written two funcs similar to cmp.Or,
and there was one in encoding/gocode as well.
While here, use the new slices package in a few more places.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: Ifd058cf54bba140c91bc317ba46ee7e83ba47e9e
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1198292
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Paul Jolly <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>

Author: mvdan

cue/load/loader_common.go

@@ -94,7 +94,7 @@ func (s *importStack) Pop() {
 }
 
 func (s *importStack) Copy() []string {
-	return append([]string{}, *s...)
+	return slices.Clone(*s)
 }
 
 type fileProcessor struct {

encoding/gocode/generator.go

@@ -16,6 +16,7 @@ package gocode
 
 import (
 	"bytes"
+	"cmp"
 	"fmt"
 	"go/ast"
 	"go/format"
@@ -159,7 +160,7 @@ func Generate(pkgPath string, inst cue.InstanceOrValue, c *Config) (b []byte, er
 
 	g.exec(loadCode, map[string]string{
 		"runtime": g.RuntimeVar,
-		"prefix":  strValue(g.Prefix, defaultPrefix),
+		"prefix":  cmp.Or(g.Prefix, defaultPrefix),
 		"data":    string(b),
 	})
 
@@ -244,14 +245,14 @@ func (g *generator) decl(name string, v cue.Value) {
 	}
 
 	g.exec(stubCode, map[string]interface{}{
-		"prefix":  strValue(g.Prefix, defaultPrefix),
+		"prefix":  cmp.Or(g.Prefix, defaultPrefix),
 		"cueName": name,   // the field name of the CUE type
 		"goType":  goType, // the receiver or argument type
 		"zero":    zero,   // the zero value of the underlying type
 
 		// @go attribute options
 		"func":     isFunc,
-		"validate": lookupName(attr, "validate", strValue(g.ValidateName, "Validate")),
+		"validate": lookupName(attr, "validate", cmp.Or(g.ValidateName, "Validate")),
 		"complete": lookupName(attr, "complete", g.CompleteName),
 	})
 }
@@ -267,13 +268,6 @@ func lookupName(attr cue.Attribute, option, config string) string {
 	return name
 }
 
-func strValue(have, fallback string) string {
-	if have == "" {
-		return fallback
-	}
-	return have
-}
-
 func mappedGoTypes(s string) bool {
 	switch s {
 	case "bool", "float32", "float64",

internal/_e2e/script_test.go

@@ -16,6 +16,8 @@ package e2e_test
 
 import (
 	"bytes"
+	"cmp"
+	"context"
 	cryptorand "crypto/rand"
 	"fmt"
 	"os"
@@ -74,17 +76,17 @@ var (
 	// githubPublicRepo is a GitHub public repository
 	// with the "cue.works authz" GitHub App installed.
 	// The repository can be entirely empty, as it's only needed for authz.
-	githubPublicRepo = envOr("GITHUB_PUBLIC_REPO", "github.com/cue-labs-modules-testing/e2e-public")
+	githubPublicRepo = cmp.Or(os.Getenv("GITHUB_PUBLIC_REPO"), "github.com/cue-labs-modules-testing/e2e-public")
 
 	// githubPublicRepo is a GitHub private repository
 	// with the "cue.works authz" GitHub App installed.
 	// The repository can be entirely empty, as it's only needed for authz.
-	githubPrivateRepo = envOr("GITHUB_PRIVATE_REPO", "github.com/cue-labs-modules-testing/e2e-private")
+	githubPrivateRepo = cmp.Or(os.Getenv("GITHUB_PRIVATE_REPO"), "github.com/cue-labs-modules-testing/e2e-private")
 
 	// gcloudRegistry is an existing Google Cloud Artifact Registry repository
 	// to publish module versions to via "cue mod publish",
 	// and authenticated via gcloud's configuration in the host environment.
-	gcloudRegistry = envOr("GCLOUD_REGISTRY", "europe-west1-docker.pkg.dev/project-unity-377819/modules-e2e-registry")
+	gcloudRegistry = cmp.Or(os.Getenv("GCLOUD_REGISTRY"), "europe-west1-docker.pkg.dev/project-unity-377819/modules-e2e-registry")
 )
 
 func TestScript(t *testing.T) {
@@ -180,13 +182,6 @@ func TestScript(t *testing.T) {
 
 func addr[T any](t T) *T { return &t }
 
-func envOr(name, fallback string) string {
-	if s := os.Getenv(name); s != "" {
-		return s
-	}
-	return fallback
-}
-
 func envMust(t *testing.T, name string) string {
 	if s := os.Getenv(name); s != "" {
 		return s

pkg/path/path_test.go

@@ -22,6 +22,7 @@ import (
 	"fmt"
 	"reflect"
 	"runtime"
+	"slices"
 	"testing"
 )
 
@@ -111,7 +112,7 @@ var wincleantests = []PathTest{
 
 func TestClean(t *testing.T) {
 	testEachOS(t, []OS{Unix, Windows, Plan9}, func(t *testing.T, os OS) {
-		tests := append([]PathTest{}, cleantests...) // TODO: replace with slices.Clone
+		tests := slices.Clone(cleantests)
 		if os == Windows {
 			for i := range tests {
 				tests[i].result = FromSlash(tests[i].result, os)
@@ -562,7 +563,7 @@ var winreltests = []RelTests{
 
 func TestRel(t *testing.T) {
 	testEachOS(t, []OS{Unix, Windows}, func(t *testing.T, os OS) {
-		tests := append([]RelTests{}, reltests...)
+		tests := slices.Clone(reltests)
 		if os == Windows {
 			for i := range tests {
 				tests[i].want = FromSlash(tests[i].want, Windows)