mirror of git://gcc.gnu.org/git/gcc.git
				
				
				
			
		
			
				
	
	
		
			651 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			Go
		
	
	
	
			
		
		
	
	
			651 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			Go
		
	
	
	
| // Copyright 2014 The Go Authors. All rights reserved.
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| // Use of this source code is governed by a BSD-style
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| // license that can be found in the LICENSE file.
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| 
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| package context
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| 
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| import (
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| 	"fmt"
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| 	"math/rand"
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| 	"runtime"
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| 	"strings"
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| 	"sync"
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| 	"time"
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| )
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| 
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| type testingT interface {
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| 	Error(args ...interface{})
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| 	Errorf(format string, args ...interface{})
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| 	Fail()
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| 	FailNow()
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| 	Failed() bool
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| 	Fatal(args ...interface{})
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| 	Fatalf(format string, args ...interface{})
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| 	Log(args ...interface{})
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| 	Logf(format string, args ...interface{})
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| 	Name() string
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| 	Skip(args ...interface{})
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| 	SkipNow()
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| 	Skipf(format string, args ...interface{})
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| 	Skipped() bool
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| }
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| 
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| // otherContext is a Context that's not one of the types defined in context.go.
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| // This lets us test code paths that differ based on the underlying type of the
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| // Context.
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| type otherContext struct {
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| 	Context
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| }
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| 
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| func XTestBackground(t testingT) {
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| 	c := Background()
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| 	if c == nil {
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| 		t.Fatalf("Background returned nil")
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| 	}
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| 	select {
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| 	case x := <-c.Done():
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| 		t.Errorf("<-c.Done() == %v want nothing (it should block)", x)
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| 	default:
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| 	}
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| 	if got, want := fmt.Sprint(c), "context.Background"; got != want {
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| 		t.Errorf("Background().String() = %q want %q", got, want)
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| 	}
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| }
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| 
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| func XTestTODO(t testingT) {
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| 	c := TODO()
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| 	if c == nil {
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| 		t.Fatalf("TODO returned nil")
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| 	}
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| 	select {
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| 	case x := <-c.Done():
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| 		t.Errorf("<-c.Done() == %v want nothing (it should block)", x)
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| 	default:
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| 	}
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| 	if got, want := fmt.Sprint(c), "context.TODO"; got != want {
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| 		t.Errorf("TODO().String() = %q want %q", got, want)
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| 	}
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| }
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| 
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| func XTestWithCancel(t testingT) {
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| 	c1, cancel := WithCancel(Background())
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| 
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| 	if got, want := fmt.Sprint(c1), "context.Background.WithCancel"; got != want {
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| 		t.Errorf("c1.String() = %q want %q", got, want)
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| 	}
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| 
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| 	o := otherContext{c1}
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| 	c2, _ := WithCancel(o)
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| 	contexts := []Context{c1, o, c2}
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| 
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| 	for i, c := range contexts {
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| 		if d := c.Done(); d == nil {
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| 			t.Errorf("c[%d].Done() == %v want non-nil", i, d)
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| 		}
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| 		if e := c.Err(); e != nil {
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| 			t.Errorf("c[%d].Err() == %v want nil", i, e)
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| 		}
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| 
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| 		select {
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| 		case x := <-c.Done():
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| 			t.Errorf("<-c.Done() == %v want nothing (it should block)", x)
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| 		default:
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| 		}
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| 	}
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| 
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| 	cancel()
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| 	time.Sleep(100 * time.Millisecond) // let cancelation propagate
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| 
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| 	for i, c := range contexts {
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| 		select {
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| 		case <-c.Done():
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| 		default:
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| 			t.Errorf("<-c[%d].Done() blocked, but shouldn't have", i)
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| 		}
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| 		if e := c.Err(); e != Canceled {
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| 			t.Errorf("c[%d].Err() == %v want %v", i, e, Canceled)
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| 		}
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| 	}
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| }
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| 
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| func contains(m map[canceler]struct{}, key canceler) bool {
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| 	_, ret := m[key]
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| 	return ret
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| }
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| 
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| func XTestParentFinishesChild(t testingT) {
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| 	// Context tree:
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| 	// parent -> cancelChild
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| 	// parent -> valueChild -> timerChild
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| 	parent, cancel := WithCancel(Background())
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| 	cancelChild, stop := WithCancel(parent)
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| 	defer stop()
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| 	valueChild := WithValue(parent, "key", "value")
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| 	timerChild, stop := WithTimeout(valueChild, 10000*time.Hour)
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| 	defer stop()
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| 
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| 	select {
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| 	case x := <-parent.Done():
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| 		t.Errorf("<-parent.Done() == %v want nothing (it should block)", x)
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| 	case x := <-cancelChild.Done():
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| 		t.Errorf("<-cancelChild.Done() == %v want nothing (it should block)", x)
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| 	case x := <-timerChild.Done():
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| 		t.Errorf("<-timerChild.Done() == %v want nothing (it should block)", x)
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| 	case x := <-valueChild.Done():
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| 		t.Errorf("<-valueChild.Done() == %v want nothing (it should block)", x)
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| 	default:
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| 	}
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| 
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| 	// The parent's children should contain the two cancelable children.
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| 	pc := parent.(*cancelCtx)
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| 	cc := cancelChild.(*cancelCtx)
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| 	tc := timerChild.(*timerCtx)
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| 	pc.mu.Lock()
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| 	if len(pc.children) != 2 || !contains(pc.children, cc) || !contains(pc.children, tc) {
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| 		t.Errorf("bad linkage: pc.children = %v, want %v and %v",
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| 			pc.children, cc, tc)
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| 	}
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| 	pc.mu.Unlock()
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| 
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| 	if p, ok := parentCancelCtx(cc.Context); !ok || p != pc {
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| 		t.Errorf("bad linkage: parentCancelCtx(cancelChild.Context) = %v, %v want %v, true", p, ok, pc)
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| 	}
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| 	if p, ok := parentCancelCtx(tc.Context); !ok || p != pc {
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| 		t.Errorf("bad linkage: parentCancelCtx(timerChild.Context) = %v, %v want %v, true", p, ok, pc)
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| 	}
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| 
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| 	cancel()
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| 
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| 	pc.mu.Lock()
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| 	if len(pc.children) != 0 {
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| 		t.Errorf("pc.cancel didn't clear pc.children = %v", pc.children)
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| 	}
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| 	pc.mu.Unlock()
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| 
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| 	// parent and children should all be finished.
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| 	check := func(ctx Context, name string) {
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| 		select {
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| 		case <-ctx.Done():
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| 		default:
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| 			t.Errorf("<-%s.Done() blocked, but shouldn't have", name)
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| 		}
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| 		if e := ctx.Err(); e != Canceled {
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| 			t.Errorf("%s.Err() == %v want %v", name, e, Canceled)
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| 		}
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| 	}
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| 	check(parent, "parent")
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| 	check(cancelChild, "cancelChild")
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| 	check(valueChild, "valueChild")
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| 	check(timerChild, "timerChild")
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| 
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| 	// WithCancel should return a canceled context on a canceled parent.
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| 	precanceledChild := WithValue(parent, "key", "value")
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| 	select {
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| 	case <-precanceledChild.Done():
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| 	default:
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| 		t.Errorf("<-precanceledChild.Done() blocked, but shouldn't have")
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| 	}
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| 	if e := precanceledChild.Err(); e != Canceled {
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| 		t.Errorf("precanceledChild.Err() == %v want %v", e, Canceled)
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| 	}
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| }
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| 
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| func XTestChildFinishesFirst(t testingT) {
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| 	cancelable, stop := WithCancel(Background())
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| 	defer stop()
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| 	for _, parent := range []Context{Background(), cancelable} {
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| 		child, cancel := WithCancel(parent)
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| 
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| 		select {
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| 		case x := <-parent.Done():
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| 			t.Errorf("<-parent.Done() == %v want nothing (it should block)", x)
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| 		case x := <-child.Done():
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| 			t.Errorf("<-child.Done() == %v want nothing (it should block)", x)
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| 		default:
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| 		}
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| 
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| 		cc := child.(*cancelCtx)
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| 		pc, pcok := parent.(*cancelCtx) // pcok == false when parent == Background()
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| 		if p, ok := parentCancelCtx(cc.Context); ok != pcok || (ok && pc != p) {
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| 			t.Errorf("bad linkage: parentCancelCtx(cc.Context) = %v, %v want %v, %v", p, ok, pc, pcok)
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| 		}
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| 
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| 		if pcok {
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| 			pc.mu.Lock()
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| 			if len(pc.children) != 1 || !contains(pc.children, cc) {
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| 				t.Errorf("bad linkage: pc.children = %v, cc = %v", pc.children, cc)
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| 			}
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| 			pc.mu.Unlock()
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| 		}
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| 
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| 		cancel()
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| 
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| 		if pcok {
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| 			pc.mu.Lock()
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| 			if len(pc.children) != 0 {
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| 				t.Errorf("child's cancel didn't remove self from pc.children = %v", pc.children)
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| 			}
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| 			pc.mu.Unlock()
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| 		}
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| 
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| 		// child should be finished.
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| 		select {
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| 		case <-child.Done():
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| 		default:
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| 			t.Errorf("<-child.Done() blocked, but shouldn't have")
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| 		}
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| 		if e := child.Err(); e != Canceled {
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| 			t.Errorf("child.Err() == %v want %v", e, Canceled)
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| 		}
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| 
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| 		// parent should not be finished.
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| 		select {
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| 		case x := <-parent.Done():
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| 			t.Errorf("<-parent.Done() == %v want nothing (it should block)", x)
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| 		default:
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| 		}
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| 		if e := parent.Err(); e != nil {
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| 			t.Errorf("parent.Err() == %v want nil", e)
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| 		}
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| 	}
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| }
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| 
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| func testDeadline(c Context, name string, failAfter time.Duration, t testingT) {
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| 	select {
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| 	case <-time.After(failAfter):
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| 		t.Fatalf("%s: context should have timed out", name)
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| 	case <-c.Done():
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| 	}
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| 	if e := c.Err(); e != DeadlineExceeded {
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| 		t.Errorf("%s: c.Err() == %v; want %v", name, e, DeadlineExceeded)
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| 	}
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| }
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| 
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| func XTestDeadline(t testingT) {
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| 	c, _ := WithDeadline(Background(), time.Now().Add(50*time.Millisecond))
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| 	if got, prefix := fmt.Sprint(c), "context.Background.WithDeadline("; !strings.HasPrefix(got, prefix) {
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| 		t.Errorf("c.String() = %q want prefix %q", got, prefix)
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| 	}
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| 	testDeadline(c, "WithDeadline", time.Second, t)
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| 
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| 	c, _ = WithDeadline(Background(), time.Now().Add(50*time.Millisecond))
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| 	o := otherContext{c}
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| 	testDeadline(o, "WithDeadline+otherContext", time.Second, t)
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| 
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| 	c, _ = WithDeadline(Background(), time.Now().Add(50*time.Millisecond))
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| 	o = otherContext{c}
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| 	c, _ = WithDeadline(o, time.Now().Add(4*time.Second))
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| 	testDeadline(c, "WithDeadline+otherContext+WithDeadline", 2*time.Second, t)
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| 
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| 	c, _ = WithDeadline(Background(), time.Now().Add(-time.Millisecond))
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| 	testDeadline(c, "WithDeadline+inthepast", time.Second, t)
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| 
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| 	c, _ = WithDeadline(Background(), time.Now())
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| 	testDeadline(c, "WithDeadline+now", time.Second, t)
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| }
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| 
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| func XTestTimeout(t testingT) {
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| 	c, _ := WithTimeout(Background(), 50*time.Millisecond)
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| 	if got, prefix := fmt.Sprint(c), "context.Background.WithDeadline("; !strings.HasPrefix(got, prefix) {
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| 		t.Errorf("c.String() = %q want prefix %q", got, prefix)
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| 	}
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| 	testDeadline(c, "WithTimeout", time.Second, t)
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| 
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| 	c, _ = WithTimeout(Background(), 50*time.Millisecond)
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| 	o := otherContext{c}
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| 	testDeadline(o, "WithTimeout+otherContext", time.Second, t)
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| 
 | |
| 	c, _ = WithTimeout(Background(), 50*time.Millisecond)
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| 	o = otherContext{c}
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| 	c, _ = WithTimeout(o, 3*time.Second)
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| 	testDeadline(c, "WithTimeout+otherContext+WithTimeout", 2*time.Second, t)
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| }
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| 
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| func XTestCanceledTimeout(t testingT) {
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| 	c, _ := WithTimeout(Background(), time.Second)
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| 	o := otherContext{c}
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| 	c, cancel := WithTimeout(o, 2*time.Second)
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| 	cancel()
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| 	time.Sleep(100 * time.Millisecond) // let cancelation propagate
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| 	select {
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| 	case <-c.Done():
 | |
| 	default:
 | |
| 		t.Errorf("<-c.Done() blocked, but shouldn't have")
 | |
| 	}
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| 	if e := c.Err(); e != Canceled {
 | |
| 		t.Errorf("c.Err() == %v want %v", e, Canceled)
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| 	}
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| }
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| 
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| type key1 int
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| type key2 int
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| 
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| var k1 = key1(1)
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| var k2 = key2(1) // same int as k1, different type
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| var k3 = key2(3) // same type as k2, different int
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| 
 | |
| func XTestValues(t testingT) {
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| 	check := func(c Context, nm, v1, v2, v3 string) {
 | |
| 		if v, ok := c.Value(k1).(string); ok == (len(v1) == 0) || v != v1 {
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| 			t.Errorf(`%s.Value(k1).(string) = %q, %t want %q, %t`, nm, v, ok, v1, len(v1) != 0)
 | |
| 		}
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| 		if v, ok := c.Value(k2).(string); ok == (len(v2) == 0) || v != v2 {
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| 			t.Errorf(`%s.Value(k2).(string) = %q, %t want %q, %t`, nm, v, ok, v2, len(v2) != 0)
 | |
| 		}
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| 		if v, ok := c.Value(k3).(string); ok == (len(v3) == 0) || v != v3 {
 | |
| 			t.Errorf(`%s.Value(k3).(string) = %q, %t want %q, %t`, nm, v, ok, v3, len(v3) != 0)
 | |
| 		}
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| 	}
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| 
 | |
| 	c0 := Background()
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| 	check(c0, "c0", "", "", "")
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| 
 | |
| 	c1 := WithValue(Background(), k1, "c1k1")
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| 	check(c1, "c1", "c1k1", "", "")
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| 
 | |
| 	if got, want := fmt.Sprint(c1), `context.Background.WithValue(1, "c1k1")`; got != want {
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| 		t.Errorf("c.String() = %q want %q", got, want)
 | |
| 	}
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| 
 | |
| 	c2 := WithValue(c1, k2, "c2k2")
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| 	check(c2, "c2", "c1k1", "c2k2", "")
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| 
 | |
| 	c3 := WithValue(c2, k3, "c3k3")
 | |
| 	check(c3, "c2", "c1k1", "c2k2", "c3k3")
 | |
| 
 | |
| 	c4 := WithValue(c3, k1, nil)
 | |
| 	check(c4, "c4", "", "c2k2", "c3k3")
 | |
| 
 | |
| 	o0 := otherContext{Background()}
 | |
| 	check(o0, "o0", "", "", "")
 | |
| 
 | |
| 	o1 := otherContext{WithValue(Background(), k1, "c1k1")}
 | |
| 	check(o1, "o1", "c1k1", "", "")
 | |
| 
 | |
| 	o2 := WithValue(o1, k2, "o2k2")
 | |
| 	check(o2, "o2", "c1k1", "o2k2", "")
 | |
| 
 | |
| 	o3 := otherContext{c4}
 | |
| 	check(o3, "o3", "", "c2k2", "c3k3")
 | |
| 
 | |
| 	o4 := WithValue(o3, k3, nil)
 | |
| 	check(o4, "o4", "", "c2k2", "")
 | |
| }
 | |
| 
 | |
| func XTestAllocs(t testingT, testingShort func() bool, testingAllocsPerRun func(int, func()) float64) {
 | |
| 	bg := Background()
 | |
| 	for _, test := range []struct {
 | |
| 		desc       string
 | |
| 		f          func()
 | |
| 		limit      float64
 | |
| 		gccgoLimit float64
 | |
| 	}{
 | |
| 		{
 | |
| 			desc:       "Background()",
 | |
| 			f:          func() { Background() },
 | |
| 			limit:      0,
 | |
| 			gccgoLimit: 0,
 | |
| 		},
 | |
| 		{
 | |
| 			desc: fmt.Sprintf("WithValue(bg, %v, nil)", k1),
 | |
| 			f: func() {
 | |
| 				c := WithValue(bg, k1, nil)
 | |
| 				c.Value(k1)
 | |
| 			},
 | |
| 			limit:      3,
 | |
| 			gccgoLimit: 3,
 | |
| 		},
 | |
| 		{
 | |
| 			desc: "WithTimeout(bg, 15*time.Millisecond)",
 | |
| 			f: func() {
 | |
| 				c, _ := WithTimeout(bg, 15*time.Millisecond)
 | |
| 				<-c.Done()
 | |
| 			},
 | |
| 			limit:      8,
 | |
| 			gccgoLimit: 18,
 | |
| 		},
 | |
| 		{
 | |
| 			desc: "WithCancel(bg)",
 | |
| 			f: func() {
 | |
| 				c, cancel := WithCancel(bg)
 | |
| 				cancel()
 | |
| 				<-c.Done()
 | |
| 			},
 | |
| 			limit:      5,
 | |
| 			gccgoLimit: 8,
 | |
| 		},
 | |
| 		{
 | |
| 			desc: "WithTimeout(bg, 5*time.Millisecond)",
 | |
| 			f: func() {
 | |
| 				c, cancel := WithTimeout(bg, 5*time.Millisecond)
 | |
| 				cancel()
 | |
| 				<-c.Done()
 | |
| 			},
 | |
| 			limit:      8,
 | |
| 			gccgoLimit: 25,
 | |
| 		},
 | |
| 	} {
 | |
| 		limit := test.limit
 | |
| 		if runtime.Compiler == "gccgo" {
 | |
| 			// gccgo does not yet do escape analysis.
 | |
| 			// TODO(iant): Remove this when gccgo does do escape analysis.
 | |
| 			limit = test.gccgoLimit
 | |
| 		}
 | |
| 		numRuns := 100
 | |
| 		if testingShort() {
 | |
| 			numRuns = 10
 | |
| 		}
 | |
| 		if n := testingAllocsPerRun(numRuns, test.f); n > limit {
 | |
| 			t.Errorf("%s allocs = %f want %d", test.desc, n, int(limit))
 | |
| 		}
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func XTestSimultaneousCancels(t testingT) {
 | |
| 	root, cancel := WithCancel(Background())
 | |
| 	m := map[Context]CancelFunc{root: cancel}
 | |
| 	q := []Context{root}
 | |
| 	// Create a tree of contexts.
 | |
| 	for len(q) != 0 && len(m) < 100 {
 | |
| 		parent := q[0]
 | |
| 		q = q[1:]
 | |
| 		for i := 0; i < 4; i++ {
 | |
| 			ctx, cancel := WithCancel(parent)
 | |
| 			m[ctx] = cancel
 | |
| 			q = append(q, ctx)
 | |
| 		}
 | |
| 	}
 | |
| 	// Start all the cancels in a random order.
 | |
| 	var wg sync.WaitGroup
 | |
| 	wg.Add(len(m))
 | |
| 	for _, cancel := range m {
 | |
| 		go func(cancel CancelFunc) {
 | |
| 			cancel()
 | |
| 			wg.Done()
 | |
| 		}(cancel)
 | |
| 	}
 | |
| 	// Wait on all the contexts in a random order.
 | |
| 	for ctx := range m {
 | |
| 		select {
 | |
| 		case <-ctx.Done():
 | |
| 		case <-time.After(1 * time.Second):
 | |
| 			buf := make([]byte, 10<<10)
 | |
| 			n := runtime.Stack(buf, true)
 | |
| 			t.Fatalf("timed out waiting for <-ctx.Done(); stacks:\n%s", buf[:n])
 | |
| 		}
 | |
| 	}
 | |
| 	// Wait for all the cancel functions to return.
 | |
| 	done := make(chan struct{})
 | |
| 	go func() {
 | |
| 		wg.Wait()
 | |
| 		close(done)
 | |
| 	}()
 | |
| 	select {
 | |
| 	case <-done:
 | |
| 	case <-time.After(1 * time.Second):
 | |
| 		buf := make([]byte, 10<<10)
 | |
| 		n := runtime.Stack(buf, true)
 | |
| 		t.Fatalf("timed out waiting for cancel functions; stacks:\n%s", buf[:n])
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func XTestInterlockedCancels(t testingT) {
 | |
| 	parent, cancelParent := WithCancel(Background())
 | |
| 	child, cancelChild := WithCancel(parent)
 | |
| 	go func() {
 | |
| 		parent.Done()
 | |
| 		cancelChild()
 | |
| 	}()
 | |
| 	cancelParent()
 | |
| 	select {
 | |
| 	case <-child.Done():
 | |
| 	case <-time.After(1 * time.Second):
 | |
| 		buf := make([]byte, 10<<10)
 | |
| 		n := runtime.Stack(buf, true)
 | |
| 		t.Fatalf("timed out waiting for child.Done(); stacks:\n%s", buf[:n])
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func XTestLayersCancel(t testingT) {
 | |
| 	testLayers(t, time.Now().UnixNano(), false)
 | |
| }
 | |
| 
 | |
| func XTestLayersTimeout(t testingT) {
 | |
| 	testLayers(t, time.Now().UnixNano(), true)
 | |
| }
 | |
| 
 | |
| func testLayers(t testingT, seed int64, testTimeout bool) {
 | |
| 	rand.Seed(seed)
 | |
| 	errorf := func(format string, a ...interface{}) {
 | |
| 		t.Errorf(fmt.Sprintf("seed=%d: %s", seed, format), a...)
 | |
| 	}
 | |
| 	const (
 | |
| 		timeout   = 200 * time.Millisecond
 | |
| 		minLayers = 30
 | |
| 	)
 | |
| 	type value int
 | |
| 	var (
 | |
| 		vals      []*value
 | |
| 		cancels   []CancelFunc
 | |
| 		numTimers int
 | |
| 		ctx       = Background()
 | |
| 	)
 | |
| 	for i := 0; i < minLayers || numTimers == 0 || len(cancels) == 0 || len(vals) == 0; i++ {
 | |
| 		switch rand.Intn(3) {
 | |
| 		case 0:
 | |
| 			v := new(value)
 | |
| 			ctx = WithValue(ctx, v, v)
 | |
| 			vals = append(vals, v)
 | |
| 		case 1:
 | |
| 			var cancel CancelFunc
 | |
| 			ctx, cancel = WithCancel(ctx)
 | |
| 			cancels = append(cancels, cancel)
 | |
| 		case 2:
 | |
| 			var cancel CancelFunc
 | |
| 			ctx, cancel = WithTimeout(ctx, timeout)
 | |
| 			cancels = append(cancels, cancel)
 | |
| 			numTimers++
 | |
| 		}
 | |
| 	}
 | |
| 	checkValues := func(when string) {
 | |
| 		for _, key := range vals {
 | |
| 			if val := ctx.Value(key).(*value); key != val {
 | |
| 				errorf("%s: ctx.Value(%p) = %p want %p", when, key, val, key)
 | |
| 			}
 | |
| 		}
 | |
| 	}
 | |
| 	select {
 | |
| 	case <-ctx.Done():
 | |
| 		errorf("ctx should not be canceled yet")
 | |
| 	default:
 | |
| 	}
 | |
| 	if s, prefix := fmt.Sprint(ctx), "context.Background."; !strings.HasPrefix(s, prefix) {
 | |
| 		t.Errorf("ctx.String() = %q want prefix %q", s, prefix)
 | |
| 	}
 | |
| 	t.Log(ctx)
 | |
| 	checkValues("before cancel")
 | |
| 	if testTimeout {
 | |
| 		select {
 | |
| 		case <-ctx.Done():
 | |
| 		case <-time.After(timeout + time.Second):
 | |
| 			errorf("ctx should have timed out")
 | |
| 		}
 | |
| 		checkValues("after timeout")
 | |
| 	} else {
 | |
| 		cancel := cancels[rand.Intn(len(cancels))]
 | |
| 		cancel()
 | |
| 		select {
 | |
| 		case <-ctx.Done():
 | |
| 		default:
 | |
| 			errorf("ctx should be canceled")
 | |
| 		}
 | |
| 		checkValues("after cancel")
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func XTestCancelRemoves(t testingT) {
 | |
| 	checkChildren := func(when string, ctx Context, want int) {
 | |
| 		if got := len(ctx.(*cancelCtx).children); got != want {
 | |
| 			t.Errorf("%s: context has %d children, want %d", when, got, want)
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	ctx, _ := WithCancel(Background())
 | |
| 	checkChildren("after creation", ctx, 0)
 | |
| 	_, cancel := WithCancel(ctx)
 | |
| 	checkChildren("with WithCancel child ", ctx, 1)
 | |
| 	cancel()
 | |
| 	checkChildren("after canceling WithCancel child", ctx, 0)
 | |
| 
 | |
| 	ctx, _ = WithCancel(Background())
 | |
| 	checkChildren("after creation", ctx, 0)
 | |
| 	_, cancel = WithTimeout(ctx, 60*time.Minute)
 | |
| 	checkChildren("with WithTimeout child ", ctx, 1)
 | |
| 	cancel()
 | |
| 	checkChildren("after canceling WithTimeout child", ctx, 0)
 | |
| }
 | |
| 
 | |
| func XTestWithCancelCanceledParent(t testingT) {
 | |
| 	parent, pcancel := WithCancel(Background())
 | |
| 	pcancel()
 | |
| 
 | |
| 	c, _ := WithCancel(parent)
 | |
| 	select {
 | |
| 	case <-c.Done():
 | |
| 	case <-time.After(5 * time.Second):
 | |
| 		t.Fatal("timeout waiting for Done")
 | |
| 	}
 | |
| 	if got, want := c.Err(), Canceled; got != want {
 | |
| 		t.Errorf("child not cancelled; got = %v, want = %v", got, want)
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func XTestWithValueChecksKey(t testingT) {
 | |
| 	panicVal := recoveredValue(func() { WithValue(Background(), []byte("foo"), "bar") })
 | |
| 	if panicVal == nil {
 | |
| 		t.Error("expected panic")
 | |
| 	}
 | |
| 	panicVal = recoveredValue(func() { WithValue(Background(), nil, "bar") })
 | |
| 	if got, want := fmt.Sprint(panicVal), "nil key"; got != want {
 | |
| 		t.Errorf("panic = %q; want %q", got, want)
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func recoveredValue(fn func()) (v interface{}) {
 | |
| 	defer func() { v = recover() }()
 | |
| 	fn()
 | |
| 	return
 | |
| }
 | |
| 
 | |
| func XTestDeadlineExceededSupportsTimeout(t testingT) {
 | |
| 	i, ok := DeadlineExceeded.(interface {
 | |
| 		Timeout() bool
 | |
| 	})
 | |
| 	if !ok {
 | |
| 		t.Fatal("DeadlineExceeded does not support Timeout interface")
 | |
| 	}
 | |
| 	if !i.Timeout() {
 | |
| 		t.Fatal("wrong value for timeout")
 | |
| 	}
 | |
| }
 |