Imported Upstream version 1.4upstream/1.4

1 files changed, 709 insertions, 0 deletions

diff --git a/src/testing/testing.go b/src/testing/testing.go
new file mode 100644
index 000000000..e54a3b8ce
--- /dev/null
+++ b/src/testing/testing.go
@@ -0,0 +1,709 @@
+// Copyright 2009 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 testing provides support for automated testing of Go packages.
+// It is intended to be used in concert with the ``go test'' command, which automates
+// execution of any function of the form
+//     func TestXxx(*testing.T)
+// where Xxx can be any alphanumeric string (but the first letter must not be in
+// [a-z]) and serves to identify the test routine.
+//
+// Within these functions, use the Error, Fail or related methods to signal failure.
+//
+// To write a new test suite, create a file whose name ends _test.go that
+// contains the TestXxx functions as described here. Put the file in the same
+// package as the one being tested. The file will be excluded from regular
+// package builds but will be included when the ``go test'' command is run.
+// For more detail, run ``go help test'' and ``go help testflag''.
+//
+// Tests and benchmarks may be skipped if not applicable with a call to
+// the Skip method of *T and *B:
+//     func TestTimeConsuming(t *testing.T) {
+//         if testing.Short() {
+//             t.Skip("skipping test in short mode.")
+//         }
+//         ...
+//     }
+//
+// Benchmarks
+//
+// Functions of the form
+//     func BenchmarkXxx(*testing.B)
+// are considered benchmarks, and are executed by the "go test" command when
+// its -bench flag is provided. Benchmarks are run sequentially.
+//
+// For a description of the testing flags, see
+// http://golang.org/cmd/go/#hdr-Description_of_testing_flags.
+//
+// A sample benchmark function looks like this:
+//     func BenchmarkHello(b *testing.B) {
+//         for i := 0; i < b.N; i++ {
+//             fmt.Sprintf("hello")
+//         }
+//     }
+//
+// The benchmark function must run the target code b.N times.
+// During benchark execution, b.N is adjusted until the benchmark function lasts
+// long enough to be timed reliably.  The output
+//     BenchmarkHello    10000000    282 ns/op
+// means that the loop ran 10000000 times at a speed of 282 ns per loop.
+//
+// If a benchmark needs some expensive setup before running, the timer
+// may be reset:
+//
+//     func BenchmarkBigLen(b *testing.B) {
+//         big := NewBig()
+//         b.ResetTimer()
+//         for i := 0; i < b.N; i++ {
+//             big.Len()
+//         }
+//     }
+//
+// If a benchmark needs to test performance in a parallel setting, it may use
+// the RunParallel helper function; such benchmarks are intended to be used with
+// the go test -cpu flag:
+//
+//     func BenchmarkTemplateParallel(b *testing.B) {
+//         templ := template.Must(template.New("test").Parse("Hello, {{.}}!"))
+//         b.RunParallel(func(pb *testing.PB) {
+//             var buf bytes.Buffer
+//             for pb.Next() {
+//                 buf.Reset()
+//                 templ.Execute(&buf, "World")
+//             }
+//         })
+//     }
+//
+// Examples
+//
+// The package also runs and verifies example code. Example functions may
+// include a concluding line comment that begins with "Output:" and is compared with
+// the standard output of the function when the tests are run. (The comparison
+// ignores leading and trailing space.) These are examples of an example:
+//
+//     func ExampleHello() {
+//             fmt.Println("hello")
+//             // Output: hello
+//     }
+//
+//     func ExampleSalutations() {
+//             fmt.Println("hello, and")
+//             fmt.Println("goodbye")
+//             // Output:
+//             // hello, and
+//             // goodbye
+//     }
+//
+// Example functions without output comments are compiled but not executed.
+//
+// The naming convention to declare examples for the package, a function F, a type T and
+// method M on type T are:
+//
+//     func Example() { ... }
+//     func ExampleF() { ... }
+//     func ExampleT() { ... }
+//     func ExampleT_M() { ... }
+//
+// Multiple example functions for a package/type/function/method may be provided by
+// appending a distinct suffix to the name. The suffix must start with a
+// lower-case letter.
+//
+//     func Example_suffix() { ... }
+//     func ExampleF_suffix() { ... }
+//     func ExampleT_suffix() { ... }
+//     func ExampleT_M_suffix() { ... }
+//
+// The entire test file is presented as the example when it contains a single
+// example function, at least one other function, type, variable, or constant
+// declaration, and no test or benchmark functions.
+//
+// Main
+//
+// It is sometimes necessary for a test program to do extra setup or teardown
+// before or after testing. It is also sometimes necessary for a test to control
+// which code runs on the main thread. To support these and other cases,
+// if a test file contains a function:
+//
+//	func TestMain(m *testing.M)
+//
+// then the generated test will call TestMain(m) instead of running the tests
+// directly. TestMain runs in the main goroutine and can do whatever setup
+// and teardown is necessary around a call to m.Run. It should then call
+// os.Exit with the result of m.Run.
+//
+// The minimal implementation of TestMain is:
+//
+//	func TestMain(m *testing.M) { os.Exit(m.Run()) }
+//
+// In effect, that is the implementation used when no TestMain is explicitly defined.
+package testing
+
+import (
+	"bytes"
+	"flag"
+	"fmt"
+	"os"
+	"runtime"
+	"runtime/pprof"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+var (
+	// The short flag requests that tests run more quickly, but its functionality
+	// is provided by test writers themselves.  The testing package is just its
+	// home.  The all.bash installation script sets it to make installation more
+	// efficient, but by default the flag is off so a plain "go test" will do a
+	// full test of the package.
+	short = flag.Bool("test.short", false, "run smaller test suite to save time")
+
+	// The directory in which to create profile files and the like. When run from
+	// "go test", the binary always runs in the source directory for the package;
+	// this flag lets "go test" tell the binary to write the files in the directory where
+	// the "go test" command is run.
+	outputDir = flag.String("test.outputdir", "", "directory in which to write profiles")
+
+	// Report as tests are run; default is silent for success.
+	chatty           = flag.Bool("test.v", false, "verbose: print additional output")
+	coverProfile     = flag.String("test.coverprofile", "", "write a coverage profile to the named file after execution")
+	match            = flag.String("test.run", "", "regular expression to select tests and examples to run")
+	memProfile       = flag.String("test.memprofile", "", "write a memory profile to the named file after execution")
+	memProfileRate   = flag.Int("test.memprofilerate", 0, "if >=0, sets runtime.MemProfileRate")
+	cpuProfile       = flag.String("test.cpuprofile", "", "write a cpu profile to the named file during execution")
+	blockProfile     = flag.String("test.blockprofile", "", "write a goroutine blocking profile to the named file after execution")
+	blockProfileRate = flag.Int("test.blockprofilerate", 1, "if >= 0, calls runtime.SetBlockProfileRate()")
+	timeout          = flag.Duration("test.timeout", 0, "if positive, sets an aggregate time limit for all tests")
+	cpuListStr       = flag.String("test.cpu", "", "comma-separated list of number of CPUs to use for each test")
+	parallel         = flag.Int("test.parallel", runtime.GOMAXPROCS(0), "maximum test parallelism")
+
+	haveExamples bool // are there examples?
+
+	cpuList []int
+)
+
+// common holds the elements common between T and B and
+// captures common methods such as Errorf.
+type common struct {
+	mu       sync.RWMutex // guards output and failed
+	output   []byte       // Output generated by test or benchmark.
+	failed   bool         // Test or benchmark has failed.
+	skipped  bool         // Test of benchmark has been skipped.
+	finished bool
+
+	start    time.Time // Time test or benchmark started
+	duration time.Duration
+	self     interface{}      // To be sent on signal channel when done.
+	signal   chan interface{} // Output for serial tests.
+}
+
+// Short reports whether the -test.short flag is set.
+func Short() bool {
+	return *short
+}
+
+// Verbose reports whether the -test.v flag is set.
+func Verbose() bool {
+	return *chatty
+}
+
+// decorate prefixes the string with the file and line of the call site
+// and inserts the final newline if needed and indentation tabs for formatting.
+func decorate(s string) string {
+	_, file, line, ok := runtime.Caller(3) // decorate + log + public function.
+	if ok {
+		// Truncate file name at last file name separator.
+		if index := strings.LastIndex(file, "/"); index >= 0 {
+			file = file[index+1:]
+		} else if index = strings.LastIndex(file, "\\"); index >= 0 {
+			file = file[index+1:]
+		}
+	} else {
+		file = "???"
+		line = 1
+	}
+	buf := new(bytes.Buffer)
+	// Every line is indented at least one tab.
+	buf.WriteByte('\t')
+	fmt.Fprintf(buf, "%s:%d: ", file, line)
+	lines := strings.Split(s, "\n")
+	if l := len(lines); l > 1 && lines[l-1] == "" {
+		lines = lines[:l-1]
+	}
+	for i, line := range lines {
+		if i > 0 {
+			// Second and subsequent lines are indented an extra tab.
+			buf.WriteString("\n\t\t")
+		}
+		buf.WriteString(line)
+	}
+	buf.WriteByte('\n')
+	return buf.String()
+}
+
+// fmtDuration returns a string representing d in the form "87.00s".
+func fmtDuration(d time.Duration) string {
+	return fmt.Sprintf("%.2fs", d.Seconds())
+}
+
+// TB is the interface common to T and B.
+type TB interface {
+	Error(args ...interface{})
+	Errorf(format string, args ...interface{})
+	Fail()
+	FailNow()
+	Failed() bool
+	Fatal(args ...interface{})
+	Fatalf(format string, args ...interface{})
+	Log(args ...interface{})
+	Logf(format string, args ...interface{})
+	Skip(args ...interface{})
+	SkipNow()
+	Skipf(format string, args ...interface{})
+	Skipped() bool
+
+	// A private method to prevent users implementing the
+	// interface and so future additions to it will not
+	// violate Go 1 compatibility.
+	private()
+}
+
+var _ TB = (*T)(nil)
+var _ TB = (*B)(nil)
+
+// T is a type passed to Test functions to manage test state and support formatted test logs.
+// Logs are accumulated during execution and dumped to standard error when done.
+type T struct {
+	common
+	name          string    // Name of test.
+	startParallel chan bool // Parallel tests will wait on this.
+}
+
+func (c *common) private() {}
+
+// Fail marks the function as having failed but continues execution.
+func (c *common) Fail() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.failed = true
+}
+
+// Failed reports whether the function has failed.
+func (c *common) Failed() bool {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.failed
+}
+
+// FailNow marks the function as having failed and stops its execution.
+// Execution will continue at the next test or benchmark.
+// FailNow must be called from the goroutine running the
+// test or benchmark function, not from other goroutines
+// created during the test. Calling FailNow does not stop
+// those other goroutines.
+func (c *common) FailNow() {
+	c.Fail()
+
+	// Calling runtime.Goexit will exit the goroutine, which
+	// will run the deferred functions in this goroutine,
+	// which will eventually run the deferred lines in tRunner,
+	// which will signal to the test loop that this test is done.
+	//
+	// A previous version of this code said:
+	//
+	//	c.duration = ...
+	//	c.signal <- c.self
+	//	runtime.Goexit()
+	//
+	// This previous version duplicated code (those lines are in
+	// tRunner no matter what), but worse the goroutine teardown
+	// implicit in runtime.Goexit was not guaranteed to complete
+	// before the test exited.  If a test deferred an important cleanup
+	// function (like removing temporary files), there was no guarantee
+	// it would run on a test failure.  Because we send on c.signal during
+	// a top-of-stack deferred function now, we know that the send
+	// only happens after any other stacked defers have completed.
+	c.finished = true
+	runtime.Goexit()
+}
+
+// log generates the output. It's always at the same stack depth.
+func (c *common) log(s string) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.output = append(c.output, decorate(s)...)
+}
+
+// Log formats its arguments using default formatting, analogous to Println,
+// and records the text in the error log. The text will be printed only if
+// the test fails or the -test.v flag is set.
+func (c *common) Log(args ...interface{}) { c.log(fmt.Sprintln(args...)) }
+
+// Logf formats its arguments according to the format, analogous to Printf,
+// and records the text in the error log. The text will be printed only if
+// the test fails or the -test.v flag is set.
+func (c *common) Logf(format string, args ...interface{}) { c.log(fmt.Sprintf(format, args...)) }
+
+// Error is equivalent to Log followed by Fail.
+func (c *common) Error(args ...interface{}) {
+	c.log(fmt.Sprintln(args...))
+	c.Fail()
+}
+
+// Errorf is equivalent to Logf followed by Fail.
+func (c *common) Errorf(format string, args ...interface{}) {
+	c.log(fmt.Sprintf(format, args...))
+	c.Fail()
+}
+
+// Fatal is equivalent to Log followed by FailNow.
+func (c *common) Fatal(args ...interface{}) {
+	c.log(fmt.Sprintln(args...))
+	c.FailNow()
+}
+
+// Fatalf is equivalent to Logf followed by FailNow.
+func (c *common) Fatalf(format string, args ...interface{}) {
+	c.log(fmt.Sprintf(format, args...))
+	c.FailNow()
+}
+
+// Skip is equivalent to Log followed by SkipNow.
+func (c *common) Skip(args ...interface{}) {
+	c.log(fmt.Sprintln(args...))
+	c.SkipNow()
+}
+
+// Skipf is equivalent to Logf followed by SkipNow.
+func (c *common) Skipf(format string, args ...interface{}) {
+	c.log(fmt.Sprintf(format, args...))
+	c.SkipNow()
+}
+
+// SkipNow marks the test as having been skipped and stops its execution.
+// Execution will continue at the next test or benchmark. See also FailNow.
+// SkipNow must be called from the goroutine running the test, not from
+// other goroutines created during the test. Calling SkipNow does not stop
+// those other goroutines.
+func (c *common) SkipNow() {
+	c.skip()
+	c.finished = true
+	runtime.Goexit()
+}
+
+func (c *common) skip() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.skipped = true
+}
+
+// Skipped reports whether the test was skipped.
+func (c *common) Skipped() bool {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.skipped
+}
+
+// Parallel signals that this test is to be run in parallel with (and only with)
+// other parallel tests.
+func (t *T) Parallel() {
+	t.signal <- (*T)(nil) // Release main testing loop
+	<-t.startParallel     // Wait for serial tests to finish
+	// Assuming Parallel is the first thing a test does, which is reasonable,
+	// reinitialize the test's start time because it's actually starting now.
+	t.start = time.Now()
+}
+
+// An internal type but exported because it is cross-package; part of the implementation
+// of the "go test" command.
+type InternalTest struct {
+	Name string
+	F    func(*T)
+}
+
+func tRunner(t *T, test *InternalTest) {
+	// When this goroutine is done, either because test.F(t)
+	// returned normally or because a test failure triggered
+	// a call to runtime.Goexit, record the duration and send
+	// a signal saying that the test is done.
+	defer func() {
+		t.duration = time.Now().Sub(t.start)
+		// If the test panicked, print any test output before dying.
+		err := recover()
+		if !t.finished && err == nil {
+			err = fmt.Errorf("test executed panic(nil) or runtime.Goexit")
+		}
+		if err != nil {
+			t.Fail()
+			t.report()
+			panic(err)
+		}
+		t.signal <- t
+	}()
+
+	t.start = time.Now()
+	test.F(t)
+	t.finished = true
+}
+
+// An internal function but exported because it is cross-package; part of the implementation
+// of the "go test" command.
+func Main(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample) {
+	os.Exit(MainStart(matchString, tests, benchmarks, examples).Run())
+}
+
+// M is a type passed to a TestMain function to run the actual tests.
+type M struct {
+	matchString func(pat, str string) (bool, error)
+	tests       []InternalTest
+	benchmarks  []InternalBenchmark
+	examples    []InternalExample
+}
+
+// MainStart is meant for use by tests generated by 'go test'.
+// It is not meant to be called directly and is not subject to the Go 1 compatibility document.
+// It may change signature from release to release.
+func MainStart(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample) *M {
+	return &M{
+		matchString: matchString,
+		tests:       tests,
+		benchmarks:  benchmarks,
+		examples:    examples,
+	}
+}
+
+// Run runs the tests. It returns an exit code to pass to os.Exit.
+func (m *M) Run() int {
+	flag.Parse()
+	parseCpuList()
+
+	before()
+	startAlarm()
+	haveExamples = len(m.examples) > 0
+	testOk := RunTests(m.matchString, m.tests)
+	exampleOk := RunExamples(m.matchString, m.examples)
+	stopAlarm()
+	if !testOk || !exampleOk {
+		fmt.Println("FAIL")
+		after()
+		return 1
+	}
+	fmt.Println("PASS")
+	RunBenchmarks(m.matchString, m.benchmarks)
+	after()
+	return 0
+}
+
+func (t *T) report() {
+	dstr := fmtDuration(t.duration)
+	format := "--- %s: %s (%s)\n%s"
+	if t.Failed() {
+		fmt.Printf(format, "FAIL", t.name, dstr, t.output)
+	} else if *chatty {
+		if t.Skipped() {
+			fmt.Printf(format, "SKIP", t.name, dstr, t.output)
+		} else {
+			fmt.Printf(format, "PASS", t.name, dstr, t.output)
+		}
+	}
+}
+
+func RunTests(matchString func(pat, str string) (bool, error), tests []InternalTest) (ok bool) {
+	ok = true
+	if len(tests) == 0 && !haveExamples {
+		fmt.Fprintln(os.Stderr, "testing: warning: no tests to run")
+		return
+	}
+	for _, procs := range cpuList {
+		runtime.GOMAXPROCS(procs)
+		// We build a new channel tree for each run of the loop.
+		// collector merges in one channel all the upstream signals from parallel tests.
+		// If all tests pump to the same channel, a bug can occur where a test
+		// kicks off a goroutine that Fails, yet the test still delivers a completion signal,
+		// which skews the counting.
+		var collector = make(chan interface{})
+
+		numParallel := 0
+		startParallel := make(chan bool)
+
+		for i := 0; i < len(tests); i++ {
+			matched, err := matchString(*match, tests[i].Name)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "testing: invalid regexp for -test.run: %s\n", err)
+				os.Exit(1)
+			}
+			if !matched {
+				continue
+			}
+			testName := tests[i].Name
+			if procs != 1 {
+				testName = fmt.Sprintf("%s-%d", tests[i].Name, procs)
+			}
+			t := &T{
+				common: common{
+					signal: make(chan interface{}),
+				},
+				name:          testName,
+				startParallel: startParallel,
+			}
+			t.self = t
+			if *chatty {
+				fmt.Printf("=== RUN %s\n", t.name)
+			}
+			go tRunner(t, &tests[i])
+			out := (<-t.signal).(*T)
+			if out == nil { // Parallel run.
+				go func() {
+					collector <- <-t.signal
+				}()
+				numParallel++
+				continue
+			}
+			t.report()
+			ok = ok && !out.Failed()
+		}
+
+		running := 0
+		for numParallel+running > 0 {
+			if running < *parallel && numParallel > 0 {
+				startParallel <- true
+				running++
+				numParallel--
+				continue
+			}
+			t := (<-collector).(*T)
+			t.report()
+			ok = ok && !t.Failed()
+			running--
+		}
+	}
+	return
+}
+
+// before runs before all testing.
+func before() {
+	if *memProfileRate > 0 {
+		runtime.MemProfileRate = *memProfileRate
+	}
+	if *cpuProfile != "" {
+		f, err := os.Create(toOutputDir(*cpuProfile))
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "testing: %s", err)
+			return
+		}
+		if err := pprof.StartCPUProfile(f); err != nil {
+			fmt.Fprintf(os.Stderr, "testing: can't start cpu profile: %s", err)
+			f.Close()
+			return
+		}
+		// Could save f so after can call f.Close; not worth the effort.
+	}
+	if *blockProfile != "" && *blockProfileRate >= 0 {
+		runtime.SetBlockProfileRate(*blockProfileRate)
+	}
+	if *coverProfile != "" && cover.Mode == "" {
+		fmt.Fprintf(os.Stderr, "testing: cannot use -test.coverprofile because test binary was not built with coverage enabled\n")
+		os.Exit(2)
+	}
+}
+
+// after runs after all testing.
+func after() {
+	if *cpuProfile != "" {
+		pprof.StopCPUProfile() // flushes profile to disk
+	}
+	if *memProfile != "" {
+		f, err := os.Create(toOutputDir(*memProfile))
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "testing: %s\n", err)
+			os.Exit(2)
+		}
+		runtime.GC() // materialize all statistics
+		if err = pprof.WriteHeapProfile(f); err != nil {
+			fmt.Fprintf(os.Stderr, "testing: can't write %s: %s\n", *memProfile, err)
+			os.Exit(2)
+		}
+		f.Close()
+	}
+	if *blockProfile != "" && *blockProfileRate >= 0 {
+		f, err := os.Create(toOutputDir(*blockProfile))
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "testing: %s\n", err)
+			os.Exit(2)
+		}
+		if err = pprof.Lookup("block").WriteTo(f, 0); err != nil {
+			fmt.Fprintf(os.Stderr, "testing: can't write %s: %s\n", *blockProfile, err)
+			os.Exit(2)
+		}
+		f.Close()
+	}
+	if cover.Mode != "" {
+		coverReport()
+	}
+}
+
+// toOutputDir returns the file name relocated, if required, to outputDir.
+// Simple implementation to avoid pulling in path/filepath.
+func toOutputDir(path string) string {
+	if *outputDir == "" || path == "" {
+		return path
+	}
+	if runtime.GOOS == "windows" {
+		// On Windows, it's clumsy, but we can be almost always correct
+		// by just looking for a drive letter and a colon.
+		// Absolute paths always have a drive letter (ignoring UNC).
+		// Problem: if path == "C:A" and outputdir == "C:\Go" it's unclear
+		// what to do, but even then path/filepath doesn't help.
+		// TODO: Worth doing better? Probably not, because we're here only
+		// under the management of go test.
+		if len(path) >= 2 {
+			letter, colon := path[0], path[1]
+			if ('a' <= letter && letter <= 'z' || 'A' <= letter && letter <= 'Z') && colon == ':' {
+				// If path starts with a drive letter we're stuck with it regardless.
+				return path
+			}
+		}
+	}
+	if os.IsPathSeparator(path[0]) {
+		return path
+	}
+	return fmt.Sprintf("%s%c%s", *outputDir, os.PathSeparator, path)
+}
+
+var timer *time.Timer
+
+// startAlarm starts an alarm if requested.
+func startAlarm() {
+	if *timeout > 0 {
+		timer = time.AfterFunc(*timeout, func() {
+			panic(fmt.Sprintf("test timed out after %v", *timeout))
+		})
+	}
+}
+
+// stopAlarm turns off the alarm.
+func stopAlarm() {
+	if *timeout > 0 {
+		timer.Stop()
+	}
+}
+
+func parseCpuList() {
+	for _, val := range strings.Split(*cpuListStr, ",") {
+		val = strings.TrimSpace(val)
+		if val == "" {
+			continue
+		}
+		cpu, err := strconv.Atoi(val)
+		if err != nil || cpu <= 0 {
+			fmt.Fprintf(os.Stderr, "testing: invalid value %q for -test.cpu\n", val)
+			os.Exit(1)
+		}
+		cpuList = append(cpuList, cpu)
+	}
+	if cpuList == nil {
+		cpuList = append(cpuList, runtime.GOMAXPROCS(-1))
+	}
+}