all: make some txtar table tests parallel

Drops `GORACE=atexit_sleep_ms=10 go test -race` time on each of these
packages as follows, as measured on my laptop:

* encoding/jsonschema: from 5.8s to 2.4s
* encoding/openapi: from 550ms to 350ms
* internal/core/compile: from 650ms to 450ms
* internal/core/export: from 550ms to 300ms
* internal/mod/modload: from 550ms to 350ms

Every bit helps, even when we're talking about fractions of a second,
as these are the slower packages when testing `./...`.
Given that CI has 8 CPUs and we have a concurrency limit,
it's best to use all the CPUs as best we can.

The savings are not just for `-race` either; for example, `go test` on
encoding/jsonschema still drops from 1.4s to 0.6s without `-race`.
However, the lack of parallelism on CPU-intensive tests is made much
more apparent by the use of `go test -race`.

CI is also at least twice as slow as my laptop, so a total saving of ~4s
here should equate to at least 8s shaved off of CI with `-race`.
Even the CI jobs using regular `go test` should save a second or two.

Note that in the export package, we also had to fix two minor bugs
where the tests were modifying globals rather than making copies
and modifying those copies. This is a better approach even without
parallelism, as otherwise we might alter the global state across tests.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: I47191d3e40022b4165b63a17aa25654fbccd1acd
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1218328
TryBot-Result: CUEcueckoo <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Roger Peppe <[email protected]>

Author: mvdan

encoding/jsonschema/decode_test.go

@@ -67,12 +67,14 @@ import (
 // As a special case, when this is "openapi", OpenAPI extraction
 // mode is enabled.
 func TestDecode(t *testing.T) {
+	t.Parallel()
 	test := cuetxtar.TxTarTest{
 		Root:   "./testdata/txtar",
 		Name:   "decode",
 		Matrix: cuetdtest.FullMatrix,
 	}
 	test.Run(t, func(t *cuetxtar.Test) {
+		t.Parallel()
 		ctx := t.CueContext()
 
 		fsys, err := txtar.FS(t.Archive)
@@ -237,6 +239,7 @@ func TestDecode(t *testing.T) {
 }
 
 func TestDecodeCRD(t *testing.T) {
+	t.Parallel()
 	test := cuetxtar.TxTarTest{
 		Root:   "./testdata/txtar",
 		Name:   "decodeCRD",
@@ -246,6 +249,7 @@ func TestDecodeCRD(t *testing.T) {
 		if versStr, ok := t.Value("version"); !ok || versStr != "k8sCRD" {
 			t.Skip("test not relevant to CRDs")
 		}
+		t.Parallel()
 
 		ctx := t.CueContext()
 
@@ -308,6 +312,7 @@ func readSchema(ctx *cue.Context, fsys fs.FS) (cue.Value, error) {
 }
 
 func TestMapURL(t *testing.T) {
+	t.Parallel()
 	v := cuecontext.New().CompileString(`
 type: "object"
 properties: x: $ref: "https://something.test/foo#/definitions/blah"
@@ -355,6 +360,7 @@ cannot determine CUE location for JSON Schema location id=https://something.test
 }
 
 func TestMapRef(t *testing.T) {
+	t.Parallel()
 	v := cuecontext.New().CompileString(`
 type: "object"
 $id: "https://this.test"
@@ -400,6 +406,7 @@ x?: blah.#Foo.bar
 }
 
 func TestMapRefExternalRefForInternalSchema(t *testing.T) {
+	t.Parallel()
 	v := cuecontext.New().CompileString(`
 type: "object"
 $id: "https://this.test"

encoding/jsonschema/external_test.go

@@ -49,17 +49,20 @@ const testDir = "testdata/external"
 // TestExternal runs the externally defined JSON Schema test suite,
 // as defined in https://github.com/json-schema-org/JSON-Schema-Test-Suite.
 func TestExternal(t *testing.T) {
+	t.Parallel()
 	tests, err := externaltest.ReadTestDir(testDir)
 	qt.Assert(t, qt.IsNil(err))
 
 	// Group the tests under a single subtest so that we can use
 	// t.Parallel and still guarantee that all tests have completed
 	// by the end.
 	cuetdtest.SmallMatrix.Run(t, "tests", func(t *testing.T, m *cuetdtest.M) {
+		t.Parallel()
 		// Run tests in deterministic order so we get some consistency between runs.
 		for _, filename := range slices.Sorted(maps.Keys(tests)) {
 			schemas := tests[filename]
 			t.Run(testName(filename), func(t *testing.T) {
+				t.Parallel()
 				for _, s := range schemas {
 					t.Run(testName(s.Description), func(t *testing.T) {
 						runExternalSchemaTests(t, m, filename, s)

encoding/openapi/decode_test.go

@@ -49,6 +49,7 @@ import (
 //
 // Set CUE_UPDATE=1 to update test files with the corresponding output.
 func TestDecode(t *testing.T) {
+	t.Parallel()
 	err := filepath.WalkDir("testdata/script", func(fullpath string, entry fs.DirEntry, err error) error {
 		if err != nil {
 			return err
@@ -58,6 +59,7 @@ func TestDecode(t *testing.T) {
 		}
 
 		t.Run(fullpath, func(t *testing.T) {
+			t.Parallel()
 			a, err := txtar.ParseFile(fullpath)
 			if err != nil {
 				t.Fatal(err)

encoding/openapi/openapi_test.go

@@ -33,6 +33,7 @@ var (
 )
 
 func TestGenerateOpenAPI(t *testing.T) {
+	t.Parallel()
 	test := cuetxtar.TxTarTest{
 		Root:   "./testdata",
 		Name:   t.Name(),
@@ -68,6 +69,7 @@ func TestGenerateOpenAPI(t *testing.T) {
 	}
 
 	test.Run(t, func(t *cuetxtar.Test) {
+		t.Parallel()
 		a := t.Instance()
 		ctx := t.CueContext()
 		v := ctx.BuildInstance(a)

internal/core/compile/compile_test.go

@@ -43,6 +43,7 @@ func TestCompile(t *testing.T) {
 	}
 
 	test.Run(t, func(t *cuetxtar.Test) {
+		t.Parallel()
 		r := runtime.New()
 		// TODO: use high-level API.
 

internal/core/export/export_test.go

@@ -39,13 +39,15 @@ import (
 )
 
 func TestDefinition(t *testing.T) {
+	t.Parallel()
 	test := cuetxtar.TxTarTest{
 		Root:   "./testdata/main",
 		Name:   "definition",
 		Matrix: cuetdtest.FullMatrix,
 	}
 
 	test.Run(t, func(t *cuetxtar.Test) {
+		t.Parallel()
 		r := t.Runtime()
 		a := t.Instance()
 

internal/core/export/self_test.go

@@ -37,6 +37,7 @@ import (
 )
 
 func TestSelfContained(t *testing.T) {
+	t.Parallel()
 	test := cuetxtar.TxTarTest{
 		Name: "self",
 		Root: "./testdata/selfcontained",
@@ -53,6 +54,7 @@ func TestSelfContained(t *testing.T) {
 	}
 
 	test.Run(t, func(t *cuetxtar.Test) {
+		t.Parallel()
 		r := t.CueContext()
 
 		a := t.Instances()
@@ -141,7 +143,7 @@ func patch(t *testing.T, r *cue.Context, orig *txtar.Archive, f *ast.File) cue.V
 
 func doDiff(t *testing.T, v, w cue.Value) {
 	var bb bytes.Buffer
-	p := diff.Schema
+	p := *diff.Schema
 	p.SkipHidden = true
 	d, script := p.Diff(v, w)
 	if d != diff.Identity {

internal/core/export/value_test.go

@@ -37,6 +37,7 @@ var exclude = map[string]string{
 }
 
 func TestValue(t *testing.T) {
+	t.Parallel()
 	const debugValue = `
 -- in.cue --
 if false {
@@ -57,6 +58,7 @@ if false {
 	}
 
 	test.Run(t, func(t *cuetxtar.Test) {
+		t.Parallel()
 		r := t.Runtime()
 		a := t.Instance()
 
@@ -70,7 +72,7 @@ if false {
 		ctx := eval.NewContext(r, v)
 		v.Finalize(ctx)
 
-		all := export.All
+		all := *export.All
 		all.ShowErrors = true
 
 		evalWithOptions := export.Profile{

internal/mod/modload/tidy_test.go

@@ -20,10 +20,12 @@ import (
 )
 
 func TestTidy(t *testing.T) {
+	t.Parallel()
 	files, err := filepath.Glob("testdata/tidy/*.txtar")
 	qt.Assert(t, qt.IsNil(err))
 	for _, f := range files {
 		t.Run(f, func(t *testing.T) {
+			t.Parallel()
 			ar, err := txtar.ParseFile(f)
 			qt.Assert(t, qt.IsNil(err))
 			tfs, err := txtar.FS(ar)

internal/mod/modload/update_test.go

@@ -20,10 +20,12 @@ import (
 )
 
 func TestUpdateVersions(t *testing.T) {
+	t.Parallel()
 	files, err := filepath.Glob("testdata/updateversions/*.txtar")
 	qt.Assert(t, qt.IsNil(err))
 	for _, f := range files {
 		t.Run(f, func(t *testing.T) {
+			t.Parallel()
 			ar, err := txtar.ParseFile(f)
 			qt.Assert(t, qt.IsNil(err))
 			tfs, err := txtar.FS(ar)