path: root/tpl/internal/go_templates/testenv/testenv.go

// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package testenv provides information about what functionality
// is available in different testing environments run by the Go team.
//
// It is an internal package because these details are specific
// to the Go team's test setup (on build.golang.org) and not
// fundamental to tests in general.
package testenv

import (
	"bytes"
	"errors"
	"flag"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"strconv"
	"strings"
	"sync"
	"testing"

	"github.com/gohugoio/hugo/tpl/internal/go_templates/cfg"
)

// Save the original environment during init for use in checks. A test
// binary may modify its environment before calling HasExec to change its
// behavior (such as mimicking a command-line tool), and that modified
// environment might cause environment checks to behave erratically.
var origEnv = os.Environ()

// Builder reports the name of the builder running this test
// (for example, "linux-amd64" or "windows-386-gce").
// If the test is not running on the build infrastructure,
// Builder returns the empty string.
func Builder() string {
	return os.Getenv("GO_BUILDER_NAME")
}

// HasGoBuild reports whether the current system can build programs with “go build”
// and then run them with os.StartProcess or exec.Command.
// Modified by Hugo (not needed)
func HasGoBuild() bool {
	return false
}

var (
	goBuildOnce sync.Once
	goBuildErr  error
)

// MustHaveGoBuild checks that the current system can build programs with “go build”
// and then run them with os.StartProcess or exec.Command.
// If not, MustHaveGoBuild calls t.Skip with an explanation.
func MustHaveGoBuild(t testing.TB) {
	if os.Getenv("GO_GCFLAGS") != "" {
		t.Helper()
		t.Skipf("skipping test: 'go build' not compatible with setting $GO_GCFLAGS")
	}
	if !HasGoBuild() {
		t.Helper()
		t.Skipf("skipping test: 'go build' unavailable: %v", goBuildErr)
	}
}

// HasGoRun reports whether the current system can run programs with “go run”.
func HasGoRun() bool {
	// For now, having go run and having go build are the same.
	return HasGoBuild()
}

// MustHaveGoRun checks that the current system can run programs with “go run”.
// If not, MustHaveGoRun calls t.Skip with an explanation.
func MustHaveGoRun(t testing.TB) {
	if !HasGoRun() {
		t.Skipf("skipping test: 'go run' not available on %s/%s", runtime.GOOS, runtime.GOARCH)
	}
}

// HasParallelism reports whether the current system can execute multiple
// threads in parallel.
// There is a copy of this function in cmd/dist/test.go.
func HasParallelism() bool {
	switch runtime.GOOS {
	case "js", "wasip1":
		return false
	}
	return true
}

// MustHaveParallelism checks that the current system can execute multiple
// threads in parallel. If not, MustHaveParallelism calls t.Skip with an explanation.
func MustHaveParallelism(t testing.TB) {
	if !HasParallelism() {
		t.Skipf("skipping test: no parallelism available on %s/%s", runtime.GOOS, runtime.GOARCH)
	}
}

// GoToolPath reports the path to the Go tool.
// It is a convenience wrapper around GoTool.
// If the tool is unavailable GoToolPath calls t.Skip.
// If the tool should be available and isn't, GoToolPath calls t.Fatal.
func GoToolPath(t testing.TB) string {
	MustHaveGoBuild(t)
	path, err := GoTool()
	if err != nil {
		t.Fatal(err)
	}
	// Add all environment variables that affect the Go command to test metadata.
	// Cached test results will be invalidate when these variables change.
	// See golang.org/issue/32285.
	for _, envVar := range strings.Fields(cfg.KnownEnv) {
		os.Getenv(envVar)
	}
	return path
}

var (
	gorootOnce sync.Once
	gorootPath string
	gorootErr  error
)

func findGOROOT() (string, error) {
	gorootOnce.Do(func() {
		gorootPath = runtime.GOROOT()
		if gorootPath != "" {
			// If runtime.GOROOT() is non-empty, assume that it is valid.
			//
			// (It might not be: for example, the user may have explicitly set GOROOT
			// to the wrong directory, or explicitly set GOROOT_FINAL but not GOROOT
			// and hasn't moved the tree to GOROOT_FINAL yet. But those cases are
			// rare, and if that happens the user can fix what they broke.)
			return
		}

		// runtime.GOROOT doesn't know where GOROOT is (perhaps because the test
		// binary was built with -trimpath, or perhaps because GOROOT_FINAL was set
		// without GOROOT and the tree hasn't been moved there yet).
		//
		// Since this is internal/testenv, we can cheat and assume that the caller
		// is a test of some package in a subdirectory of GOROOT/src. ('go test'
		// runs the test in the directory containing the packaged under test.) That
		// means that if we start walking up the tree, we should eventually find
		// GOROOT/src/go.mod, and we can report the parent directory of that.
		//
		// Notably, this works even if we can't run 'go env GOROOT' as a
		// subprocess.

		cwd, err := os.Getwd()
		if err != nil {
			gorootErr = fmt.Errorf("finding GOROOT: %w", err)
			return
		}

		dir := cwd
		for {
			parent := filepath.Dir(dir)
			if parent == dir {
				// dir is either "." or only a volume name.
				gorootErr = fmt.Errorf("failed to locate GOROOT/src in any parent directory")
				return
			}

			if base := filepath.Base(dir); base != "src" {
				dir = parent
				continue // dir cannot be GOROOT/src if it doesn't end in "src".
			}

			b, err := os.ReadFile(filepath.Join(dir, "go.mod"))
			if err != nil {
				if os.IsNotExist(err) {
					dir = parent
					continue
				}
				gorootErr = fmt.Errorf("finding GOROOT: %w", err)
				return
			}
			goMod := string(b)

			for goMod != "" {
				var line string
				line, goMod, _ = strings.Cut(goMod, "\n")
				fields := strings.Fields(line)
				if len(fields) >= 2 && fields[0] == "module" && fields[1] == "std" {
					// Found "module std", which is the module declaration in GOROOT/src!
					gorootPath = parent
					return
				}
			}
		}
	})

	return gorootPath, gorootErr
}

// GOROOT reports the path to the directory containing the root of the Go
// project source tree. This is normally equivalent to runtime.GOROOT, but
// works even if the test binary was built with -trimpath and cannot exec
// 'go env GOROOT'.
//
// If GOROOT cannot be found, GOROOT skips t if t is non-nil,
// or panics otherwise.
func GOROOT(t testing.TB) string {
	path, err := findGOROOT()
	if err != nil {
		if t == nil {
			panic(err)
		}
		t.Helper()
		t.Skip(err)
	}
	return path
}

// GoTool reports the path to the Go tool.
func GoTool() (string, error) {
	if !HasGoBuild() {
		return "", errors.New("platform cannot run go tool")
	}
	goToolOnce.Do(func() {
		goToolPath, goToolErr = exec.LookPath("go")
	})
	return goToolPath, goToolErr
}

var (
	goToolOnce sync.Once
	goToolPath string
	goToolErr  error
)

// HasSrc reports whether the entire source tree is available under GOROOT.
func HasSrc() bool {
	switch runtime.GOOS {
	case "ios":
		return false
	}
	return true
}

// HasExternalNetwork reports whether the current system can use
// external (non-localhost) networks.
func HasExternalNetwork() bool {
	return !testing.Short() && runtime.GOOS != "js" && runtime.GOOS !=