| // Copyright 2014 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 context |
| |
| import ( |
| "fmt" |
| "math/rand" |
| "runtime" |
| "strings" |
| "sync" |
| "time" |
| ) |
| |
| type testingT 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{}) |
| Name() string |
| Skip(args ...interface{}) |
| SkipNow() |
| Skipf(format string, args ...interface{}) |
| Skipped() bool |
| } |
| |
| // otherContext is a Context that's not one of the types defined in context.go. |
| // This lets us test code paths that differ based on the underlying type of the |
| // Context. |
| type otherContext struct { |
| Context |
| } |
| |
| func XTestBackground(t testingT) { |
| c := Background() |
| if c == nil { |
| t.Fatalf("Background returned nil") |
| } |
| select { |
| case x := <-c.Done(): |
| t.Errorf("<-c.Done() == %v want nothing (it should block)", x) |
| default: |
| } |
| if got, want := fmt.Sprint(c), "context.Background"; got != want { |
| t.Errorf("Background().String() = %q want %q", got, want) |
| } |
| } |
| |
| func XTestTODO(t testingT) { |
| c := TODO() |
| if c == nil { |
| t.Fatalf("TODO returned nil") |
| } |
| select { |
| case x := <-c.Done(): |
| t.Errorf("<-c.Done() == %v want nothing (it should block)", x) |
| default: |
| } |
| if got, want := fmt.Sprint(c), "context.TODO"; got != want { |
| t.Errorf("TODO().String() = %q want %q", got, want) |
| } |
| } |
| |
| func XTestWithCancel(t testingT) { |
| c1, cancel := WithCancel(Background()) |
| |
| if got, want := fmt.Sprint(c1), "context.Background.WithCancel"; got != want { |
| t.Errorf("c1.String() = %q want %q", got, want) |
| } |
| |
| o := otherContext{c1} |
| c2, _ := WithCancel(o) |
| contexts := []Context{c1, o, c2} |
| |
| for i, c := range contexts { |
| if d := c.Done(); d == nil { |
| t.Errorf("c[%d].Done() == %v want non-nil", i, d) |
| } |
| if e := c.Err(); e != nil { |
| t.Errorf("c[%d].Err() == %v want nil", i, e) |
| } |
| |
| select { |
| case x := <-c.Done(): |
| t.Errorf("<-c.Done() == %v want nothing (it should block)", x) |
| default: |
| } |
| } |
| |
| cancel() |
| time.Sleep(100 * time.Millisecond) // let cancelation propagate |
| |
| for i, c := range contexts { |
| select { |
| case <-c.Done(): |
| default: |
| t.Errorf("<-c[%d].Done() blocked, but shouldn't have", i) |
| } |
| if e := c.Err(); e != Canceled { |
| t.Errorf("c[%d].Err() == %v want %v", i, e, Canceled) |
| } |
| } |
| } |
| |
| func contains(m map[canceler]struct{}, key canceler) bool { |
| _, ret := m[key] |
| return ret |
| } |
| |
| func XTestParentFinishesChild(t testingT) { |
| // Context tree: |
| // parent -> cancelChild |
| // parent -> valueChild -> timerChild |
| parent, cancel := WithCancel(Background()) |
| cancelChild, stop := WithCancel(parent) |
| defer stop() |
| valueChild := WithValue(parent, "key", "value") |
| timerChild, stop := WithTimeout(valueChild, 10000*time.Hour) |
| defer stop() |
| |
| select { |
| case x := <-parent.Done(): |
| t.Errorf("<-parent.Done() == %v want nothing (it should block)", x) |
| case x := <-cancelChild.Done(): |
| t.Errorf("<-cancelChild.Done() == %v want nothing (it should block)", x) |
| case x := <-timerChild.Done(): |
| t.Errorf("<-timerChild.Done() == %v want nothing (it should block)", x) |
| case x := <-valueChild.Done(): |
| t.Errorf("<-valueChild.Done() == %v want nothing (it should block)", x) |
| default: |
| } |
| |
| // The parent's children should contain the two cancelable children. |
| pc := parent.(*cancelCtx) |
| cc := cancelChild.(*cancelCtx) |
| test := timerChild.(*timerCtx) |
| pc.mu.Lock() |
| if len(pc.children) != 2 || !contains(pc.children, cc) || !contains(pc.children, test) { |
| t.Errorf("bad linkage: pc.children = %v, want %v and %v", |
| pc.children, cc, test) |
| } |
| pc.mu.Unlock() |
| |
| if p, ok := parentCancelCtx(cc.Context); !ok || p != pc { |
| t.Errorf("bad linkage: parentCancelCtx(cancelChild.Context) = %v, %v want %v, true", p, ok, pc) |
| } |
| if p, ok := parentCancelCtx(test.Context); !ok || p != pc { |
| t.Errorf("bad linkage: parentCancelCtx(timerChild.Context) = %v, %v want %v, true", p, ok, pc) |
| } |
| |
| cancel() |
| |
| pc.mu.Lock() |
| if len(pc.children) != 0 { |
| t.Errorf("pc.cancel didn't clear pc.children = %v", pc.children) |
| } |
| pc.mu.Unlock() |
| |
| // parent and children should all be finished. |
| check := func(ctx Context, name string) { |
| select { |
| case <-ctx.Done(): |
| default: |
| t.Errorf("<-%s.Done() blocked, but shouldn't have", name) |
| } |
| if e := ctx.Err(); e != Canceled { |
| t.Errorf("%s.Err() == %v want %v", name, e, Canceled) |
| } |
| } |
| check(parent, "parent") |
| check(cancelChild, "cancelChild") |
| check(valueChild, "valueChild") |
| check(timerChild, "timerChild") |
| |
| // WithCancel should return a canceled context on a canceled parent. |
| precanceledChild := WithValue(parent, "key", "value") |
| select { |
| case <-precanceledChild.Done(): |
| default: |
| t.Errorf("<-precanceledChild.Done() blocked, but shouldn't have") |
| } |
| if e := precanceledChild.Err(); e != Canceled { |
| t.Errorf("precanceledChild.Err() == %v want %v", e, Canceled) |
| } |
| } |
| |
| func XTestChildFinishesFirst(t testingT) { |
| cancelable, stop := WithCancel(Background()) |
| defer stop() |
| for _, parent := range []Context{Background(), cancelable} { |
| child, cancel := WithCancel(parent) |
| |
| select { |
| case x := <-parent.Done(): |
| t.Errorf("<-parent.Done() == %v want nothing (it should block)", x) |
| case x := <-child.Done(): |
| t.Errorf("<-child.Done() == %v want nothing (it should block)", x) |
| default: |
| } |
| |
| cc := child.(*cancelCtx) |
| pc, pcok := parent.(*cancelCtx) // pcok == false when parent == Background() |
| if p, ok := parentCancelCtx(cc.Context); ok != pcok || (ok && pc != p) { |
| t.Errorf("bad linkage: parentCancelCtx(cc.Context) = %v, %v want %v, %v", p, ok, pc, pcok) |
| } |
| |
| if pcok { |
| pc.mu.Lock() |
| if len(pc.children) != 1 || !contains(pc.children, cc) { |
| t.Errorf("bad linkage: pc.children = %v, cc = %v", pc.children, cc) |
| } |
| pc.mu.Unlock() |
| } |
| |
| cancel() |
| |
| if pcok { |
| pc.mu.Lock() |
| if len(pc.children) != 0 { |
| t.Errorf("child's cancel didn't remove self from pc.children = %v", pc.children) |
| } |
| pc.mu.Unlock() |
| } |
| |
| // child should be finished. |
| select { |
| case <-child.Done(): |
| default: |
| t.Errorf("<-child.Done() blocked, but shouldn't have") |
| } |
| if e := child.Err(); e != Canceled { |
| t.Errorf("child.Err() == %v want %v", e, Canceled) |
| } |
| |
| // parent should not be finished. |
| select { |
| case x := <-parent.Done(): |
| t.Errorf("<-parent.Done() == %v want nothing (it should block)", x) |
| default: |
| } |
| if e := parent.Err(); e != nil { |
| t.Errorf("parent.Err() == %v want nil", e) |
| } |
| } |
| } |
| |
| func testDeadline(c Context, name string, failAfter time.Duration, t testingT) { |
| select { |
| case <-time.After(failAfter): |
| t.Fatalf("%s: context should have timed out", name) |
| case <-c.Done(): |
| } |
| if e := c.Err(); e != DeadlineExceeded { |
| t.Errorf("%s: c.Err() == %v; want %v", name, e, DeadlineExceeded) |
| } |
| } |
| |
| func XTestDeadline(t testingT) { |
| c, _ := WithDeadline(Background(), time.Now().Add(50*time.Millisecond)) |
| if got, prefix := fmt.Sprint(c), "context.Background.WithDeadline("; !strings.HasPrefix(got, prefix) { |
| t.Errorf("c.String() = %q want prefix %q", got, prefix) |
| } |
| testDeadline(c, "WithDeadline", time.Second, t) |
| |
| c, _ = WithDeadline(Background(), time.Now().Add(50*time.Millisecond)) |
| o := otherContext{c} |
| testDeadline(o, "WithDeadline+otherContext", time.Second, t) |
| |
| c, _ = WithDeadline(Background(), time.Now().Add(50*time.Millisecond)) |
| o = otherContext{c} |
| c, _ = WithDeadline(o, time.Now().Add(4*time.Second)) |
| testDeadline(c, "WithDeadline+otherContext+WithDeadline", 2*time.Second, t) |
| |
| c, _ = WithDeadline(Background(), time.Now().Add(-time.Millisecond)) |
| testDeadline(c, "WithDeadline+inthepast", time.Second, t) |
| |
| c, _ = WithDeadline(Background(), time.Now()) |
| testDeadline(c, "WithDeadline+now", time.Second, t) |
| } |
| |
| func XTestTimeout(t testingT) { |
| c, _ := WithTimeout(Background(), 50*time.Millisecond) |
| if got, prefix := fmt.Sprint(c), "context.Background.WithDeadline("; !strings.HasPrefix(got, prefix) { |
| t.Errorf("c.String() = %q want prefix %q", got, prefix) |
| } |
| testDeadline(c, "WithTimeout", time.Second, t) |
| |
| c, _ = WithTimeout(Background(), 50*time.Millisecond) |
| o := otherContext{c} |
| testDeadline(o, "WithTimeout+otherContext", time.Second, t) |
| |
| c, _ = WithTimeout(Background(), 50*time.Millisecond) |
| o = otherContext{c} |
| c, _ = WithTimeout(o, 3*time.Second) |
| testDeadline(c, "WithTimeout+otherContext+WithTimeout", 2*time.Second, t) |
| } |
| |
| func XTestCanceledTimeout(t testingT) { |
| c, _ := WithTimeout(Background(), time.Second) |
| o := otherContext{c} |
| c, cancel := WithTimeout(o, 2*time.Second) |
| cancel() |
| time.Sleep(100 * time.Millisecond) // let cancelation propagate |
| select { |
| case <-c.Done(): |
| default: |
| t.Errorf("<-c.Done() blocked, but shouldn't have") |
| } |
| if e := c.Err(); e != Canceled { |
| t.Errorf("c.Err() == %v want %v", e, Canceled) |
| } |
| } |
| |
| type key1 int |
| type key2 int |
| |
| var k1 = key1(1) |
| var k2 = key2(1) // same int as k1, different type |
| var k3 = key2(3) // same type as k2, different int |
| |
| func XTestValues(t testingT) { |
| check := func(c Context, nm, v1, v2, v3 string) { |
| if v, ok := c.Value(k1).(string); ok == (len(v1) == 0) || v != v1 { |
| t.Errorf(`%s.Value(k1).(string) = %q, %t want %q, %t`, nm, v, ok, v1, len(v1) != 0) |
| } |
| if v, ok := c.Value(k2).(string); ok == (len(v2) == 0) || v != v2 { |
| t.Errorf(`%s.Value(k2).(string) = %q, %t want %q, %t`, nm, v, ok, v2, len(v2) != 0) |
| } |
| 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) |
| } |
| } |
| |
| c0 := Background() |
| check(c0, "c0", "", "", "") |
| |
| c1 := WithValue(Background(), k1, "c1k1") |
| check(c1, "c1", "c1k1", "", "") |
| |
| if got, want := fmt.Sprint(c1), `context.Background.WithValue(1, "c1k1")`; got != want { |
| t.Errorf("c.String() = %q want %q", got, want) |
| } |
| |
| c2 := WithValue(c1, k2, "c2k2") |
| check(c2, "c2", "c1k1", "c2k2", "") |
| |
| 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: 15, |
| }, |
| { |
| 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") |
| } |
| } |
