github.com/slayercat/go@v0.0.0-20170428012452-c51559813f61/src/net/http/main_test.go (about)

     1  // Copyright 2013 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package http_test
     6  
     7  import (
     8  	"fmt"
     9  	"io/ioutil"
    10  	"log"
    11  	"net/http"
    12  	"os"
    13  	"runtime"
    14  	"sort"
    15  	"strings"
    16  	"testing"
    17  	"time"
    18  )
    19  
    20  var quietLog = log.New(ioutil.Discard, "", 0)
    21  
    22  func TestMain(m *testing.M) {
    23  	v := m.Run()
    24  	if v == 0 && goroutineLeaked() {
    25  		os.Exit(1)
    26  	}
    27  	os.Exit(v)
    28  }
    29  
    30  func interestingGoroutines() (gs []string) {
    31  	buf := make([]byte, 2<<20)
    32  	buf = buf[:runtime.Stack(buf, true)]
    33  	for _, g := range strings.Split(string(buf), "\n\n") {
    34  		sl := strings.SplitN(g, "\n", 2)
    35  		if len(sl) != 2 {
    36  			continue
    37  		}
    38  		stack := strings.TrimSpace(sl[1])
    39  		if stack == "" ||
    40  			strings.Contains(stack, "created by net.startServer") ||
    41  			strings.Contains(stack, "created by testing.RunTests") ||
    42  			strings.Contains(stack, "closeWriteAndWait") ||
    43  			strings.Contains(stack, "testing.Main(") ||
    44  			// These only show up with GOTRACEBACK=2; Issue 5005 (comment 28)
    45  			strings.Contains(stack, "runtime.goexit") ||
    46  			strings.Contains(stack, "created by runtime.gc") ||
    47  			strings.Contains(stack, "net/http_test.interestingGoroutines") ||
    48  			strings.Contains(stack, "runtime.MHeap_Scavenger") {
    49  			continue
    50  		}
    51  		gs = append(gs, stack)
    52  	}
    53  	sort.Strings(gs)
    54  	return
    55  }
    56  
    57  // Verify the other tests didn't leave any goroutines running.
    58  func goroutineLeaked() bool {
    59  	if testing.Short() {
    60  		// not counting goroutines for leakage in -short mode
    61  		return false
    62  	}
    63  
    64  	var stackCount map[string]int
    65  	for i := 0; i < 5; i++ {
    66  		n := 0
    67  		stackCount = make(map[string]int)
    68  		gs := interestingGoroutines()
    69  		for _, g := range gs {
    70  			stackCount[g]++
    71  			n++
    72  		}
    73  		if n == 0 {
    74  			return false
    75  		}
    76  		// Wait for goroutines to schedule and die off:
    77  		time.Sleep(100 * time.Millisecond)
    78  	}
    79  	fmt.Fprintf(os.Stderr, "Too many goroutines running after net/http test(s).\n")
    80  	for stack, count := range stackCount {
    81  		fmt.Fprintf(os.Stderr, "%d instances of:\n%s\n", count, stack)
    82  	}
    83  	return true
    84  }
    85  
    86  // setParallel marks t as a parallel test if we're in short mode
    87  // (all.bash), but as a serial test otherwise. Using t.Parallel isn't
    88  // compatible with the afterTest func in non-short mode.
    89  func setParallel(t *testing.T) {
    90  	if testing.Short() {
    91  		t.Parallel()
    92  	}
    93  }
    94  
    95  func afterTest(t testing.TB) {
    96  	http.DefaultTransport.(*http.Transport).CloseIdleConnections()
    97  	if testing.Short() {
    98  		return
    99  	}
   100  	var bad string
   101  	badSubstring := map[string]string{
   102  		").readLoop(":                                  "a Transport",
   103  		").writeLoop(":                                 "a Transport",
   104  		"created by net/http/httptest.(*Server).Start": "an httptest.Server",
   105  		"timeoutHandler":                               "a TimeoutHandler",
   106  		"net.(*netFD).connect(":                        "a timing out dial",
   107  		").noteClientGone(":                            "a closenotifier sender",
   108  	}
   109  	var stacks string
   110  	for i := 0; i < 4; i++ {
   111  		bad = ""
   112  		stacks = strings.Join(interestingGoroutines(), "\n\n")
   113  		for substr, what := range badSubstring {
   114  			if strings.Contains(stacks, substr) {
   115  				bad = what
   116  			}
   117  		}
   118  		if bad == "" {
   119  			return
   120  		}
   121  		// Bad stuff found, but goroutines might just still be
   122  		// shutting down, so give it some time.
   123  		time.Sleep(250 * time.Millisecond)
   124  	}
   125  	t.Errorf("Test appears to have leaked %s:\n%s", bad, stacks)
   126  }
   127  
   128  // waitCondition reports whether fn eventually returned true,
   129  // checking immediately and then every checkEvery amount,
   130  // until waitFor has elapsed, at which point it returns false.
   131  func waitCondition(waitFor, checkEvery time.Duration, fn func() bool) bool {
   132  	deadline := time.Now().Add(waitFor)
   133  	for time.Now().Before(deadline) {
   134  		if fn() {
   135  			return true
   136  		}
   137  		time.Sleep(checkEvery)
   138  	}
   139  	return false
   140  }
   141  
   142  // waitErrCondition is like waitCondition but with errors instead of bools.
   143  func waitErrCondition(waitFor, checkEvery time.Duration, fn func() error) error {
   144  	deadline := time.Now().Add(waitFor)
   145  	var err error
   146  	for time.Now().Before(deadline) {
   147  		if err = fn(); err == nil {
   148  			return nil
   149  		}
   150  		time.Sleep(checkEvery)
   151  	}
   152  	return err
   153  }