vendor tsgo

tools/tsgo/internal/testutil/jstest/node.go

@@ -0,0 +1,95 @@
+package jstest
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"sync"
+	"testing"
+
+	"github.com/microsoft/typescript-go/internal/json"
+	"github.com/microsoft/typescript-go/internal/repo"
+	"github.com/microsoft/typescript-go/internal/tspath"
+)
+
+const loaderScript = `import script from "./script.mjs";
+process.stdout.write(JSON.stringify(await script(...process.argv.slice(2))));`
+
+var getNodeExeOnce = sync.OnceValue(func() string {
+	const exeName = "node"
+	exe, err := exec.LookPath(exeName)
+	if err != nil {
+		return ""
+	}
+	return exe
+})
+
+// EvalNodeScript imports a Node.js script that default-exports a single function,
+// calls it with the provided arguments, and unmarshals the JSON-stringified
+// awaited return value into T.
+func EvalNodeScript[T any](t testing.TB, script string, dir string, args ...string) (result T, err error) {
+	return evalNodeScript[T](t, script, loaderScript, dir, args...)
+}
+
+// EvalNodeScriptWithTS is like EvalNodeScript, but provides the TypeScript
+// library to the script as the first argument.
+func EvalNodeScriptWithTS[T any](t testing.TB, script string, dir string, args ...string) (result T, err error) {
+	if dir == "" {
+		dir = t.TempDir()
+	}
+	tsSrc := tspath.NormalizePath(filepath.Join(repo.RootPath(), "node_modules/typescript/lib/typescript.js"))
+	if tsSrc[0] == '/' {
+		tsSrc = "file://" + tsSrc
+	} else {
+		tsSrc = "file:///" + tsSrc
+	}
+	tsLoaderScript := fmt.Sprintf(`import script from "./script.mjs";
+import * as ts from "%s";
+process.stdout.write(JSON.stringify(await script(ts, ...process.argv.slice(2))));`, tsSrc)
+	return evalNodeScript[T](t, script, tsLoaderScript, dir, args...)
+}
+
+func SkipIfNoNodeJS(t testing.TB) {
+	t.Helper()
+	if getNodeExeOnce() == "" {
+		t.Skip("Node.js not found")
+	}
+}
+
+func evalNodeScript[T any](t testing.TB, script string, loader string, dir string, args ...string) (result T, err error) {
+	t.Helper()
+	exe := getNodeExe(t)
+	scriptPath := dir + "/script.mjs"
+	if err = os.WriteFile(scriptPath, []byte(script), 0o644); err != nil {
+		return result, err
+	}
+	loaderPath := dir + "/loader.mjs"
+	if err = os.WriteFile(loaderPath, []byte(loader), 0o644); err != nil {
+		return result, err
+	}
+
+	execArgs := make([]string, 0, 1+len(args))
+	execArgs = append(execArgs, loaderPath)
+	execArgs = append(execArgs, args...)
+	execCmd := exec.Command(exe, execArgs...)
+	execCmd.Dir = dir
+	output, err := execCmd.CombinedOutput()
+	if err != nil {
+		return result, fmt.Errorf("failed to run node: %w\n%s", err, output)
+	}
+
+	if err = json.Unmarshal(output, &result); err != nil {
+		return result, fmt.Errorf("failed to unmarshal JSON output: %w", err)
+	}
+
+	return result, nil
+}
+
+func getNodeExe(t testing.TB) string {
+	if exe := getNodeExeOnce(); exe != "" {
+		return exe
+	}
+	t.Fatal("Node.js not found")
+	return ""
+}