1 files changed, 404 insertions, 0 deletions
diff --git a/src/go/doc/testdata/testing.go b/src/go/doc/testdata/testing.go
new file mode 100644
index 000000000..93ed494c3
--- /dev/null
+++ b/src/go/doc/testdata/testing.go
@@ -0,0 +1,404 @@
+// 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'' utility, 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.
+// These TestXxx routines should be declared within the package they are testing.
+//
+// Functions of the form
+//     func BenchmarkXxx(*testing.B)
+// are considered benchmarks, and are executed by go test when the -test.bench
+// flag is provided.
+//
+// A sample benchmark function looks like this:
+//     func BenchmarkHello(b *testing.B) {
+//         for i := 0; i < b.N; i++ {
+//             fmt.Sprintf("hello")
+//         }
+//     }
+// The benchmark package will vary b.N until the benchmark function lasts
+// long enough to be timed reliably.  The output
+//     testing.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 stopped:
+//     func BenchmarkBigLen(b *testing.B) {
+//         b.StopTimer()
+//         big := NewBig()
+//         b.StartTimer()
+//         for i := 0; i < b.N; i++ {
+//             big.Len()
+//         }
+//     }
+package testing
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"runtime"
+	"runtime/pprof"
+	"strconv"
+	"strings"
+	"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")
+
+	// Report as tests are run; default is silent for success.
+	chatty         = flag.Bool("test.v", false, "verbose: print additional output")
+	match          = flag.String("test.run", "", "regular expression to select tests 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")
+	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")
+
+	cpuList []int
+)
+
+// common holds the elements common between T and B and
+// captures common methods such as Errorf.
+type common struct {
+	output   []byte    // Output generated by test or benchmark.
+	failed   bool      // Test or benchmark has failed.
+	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
+}
+
+// decorate inserts the final newline if needed and indentation tabs for formatting.
+// If addFileLine is true, it also prefixes the string with the file and line of the call site.
+func decorate(s string, addFileLine bool) string {
+	if addFileLine {
+		_, 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
+		}
+		s = fmt.Sprintf("%s:%d: %s", file, line, s)
+	}
+	s = "\t" + s // Every line is indented at least one tab.
+	n := len(s)
+	if n > 0 && s[n-1] != '\n' {
+		s += "\n"
+		n++
+	}
+	for i := 0; i < n-1; i++ { // -1 to avoid final newline
+		if s[i] == '\n' {
+			// Second and subsequent lines are indented an extra tab.
+			return s[0:i+1] + "\t" + decorate(s[i+1:n], false)
+		}
+	}
+	return s
+}
+
+// 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.
+}
+
+// Fail marks the function as having failed but continues execution.
+func (c *common) Fail() { c.failed = true }
+
+// Failed reports whether the function has failed.
+func (c *common) Failed() bool { return c.failed }
+
+// FailNow marks the function as having failed and stops its execution.
+// Execution will continue at the next Test.
+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.
+	runtime.Goexit()
+}
+
+// log generates the output. It's always at the same stack depth.
+func (c *common) log(s string) {
+	c.output = append(c.output, decorate(s, true)...)
+}
+
+// Log formats its arguments using default formatting, analogous to Println(),
+// and records the text in the error log.
+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.
+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()
+}
+
+// Parallel signals that this test is to be run in parallel with (and only with)
+// other parallel tests in this CPU group.
+func (t *T) Parallel() {
+	t.signal <- (*T)(nil) // Release main testing loop
+	<-t.startParallel     // Wait for serial tests to finish
+}
+
+// An internal type but exported because it is cross-package; part of the implementation
+// of go test.
+type InternalTest struct {
+	Name string
+	F    func(*T)
+}
+
+func tRunner(t *T, test *InternalTest) {
+	t.start = time.Now()
+
+	// 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)
+		t.signal <- t
+	}()
+
+	test.F(t)
+}
+
+// An internal function but exported because it is cross-package; part of the implementation
+// of go test.
+func Main(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample) {
+	flag.Parse()
+	parseCpuList()
+
+	before()
+	startAlarm()
+	testOk := RunTests(matchString, tests)
+	exampleOk := RunExamples(examples)
+	if !testOk || !exampleOk {
+		fmt.Println("FAIL")
+		os.Exit(1)
+	}
+	fmt.Println("PASS")
+	stopAlarm()
+	RunBenchmarks(matchString, benchmarks)
+	after()
+}
+
+func (t *T) report() {
+	tstr := fmt.Sprintf("(%.2f seconds)", t.duration.Seconds())
+	format := "--- %s: %s %s\n%s"
+	if t.failed {
+		fmt.Printf(format, "FAIL", t.name, tstr, t.output)
+	} else if *chatty {
+		fmt.Printf(format, "PASS", t.name, tstr, t.output)
+	}
+}
+
+func RunTests(matchString func(pat, str string) (bool, error), tests []InternalTest) (ok bool) {
+	ok = true
+	if len(tests) == 0 {
+		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(*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.
+	}
+
+}
+
+// after runs after all testing.
+func after() {
+	if *cpuProfile != "" {
+		pprof.StopCPUProfile() // flushes profile to disk
+	}
+	if *memProfile != "" {
+		f, err := os.Create(*memProfile)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "testing: %s", err)
+			return
+		}
+		if err = pprof.WriteHeapProfile(f); err != nil {
+			fmt.Fprintf(os.Stderr, "testing: can't write %s: %s", *memProfile, err)
+		}
+		f.Close()
+	}
+}
+
+var timer *time.Timer
+
+// startAlarm starts an alarm if requested.
+func startAlarm() {
+	if *timeout > 0 {
+		timer = time.AfterFunc(*timeout, alarm)
+	}
+}
+
+// stopAlarm turns off the alarm.
+func stopAlarm() {
+	if *timeout > 0 {
+		timer.Stop()
+	}
+}
+
+// alarm is called if the timeout expires.
+func alarm() {
+	panic("test timed out")
+}
+
+func parseCpuList() {
+	if len(*cpuListStr) == 0 {
+		cpuList = append(cpuList, runtime.GOMAXPROCS(-1))
+	} else {
+		for _, val := range strings.Split(*cpuListStr, ",") {
+			cpu, err := strconv.Atoi(val)
+			if err != nil || cpu <= 0 {
+				fmt.Fprintf(os.Stderr, "testing: invalid value %q for -test.cpu", val)
+				os.Exit(1)
+			}
+			cpuList = append(cpuList, cpu)
+		}
+	}
+}