You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
583 lines
15 KiB
583 lines
15 KiB
// 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. |
|
|
|
// +build !go1.7 |
|
|
|
package context |
|
|
|
import ( |
|
"fmt" |
|
"math/rand" |
|
"runtime" |
|
"strings" |
|
"sync" |
|
"testing" |
|
"time" |
|
) |
|
|
|
// 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 TestBackground(t *testing.T) { |
|
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 TestTODO(t *testing.T) { |
|
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 TestWithCancel(t *testing.T) { |
|
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 TestParentFinishesChild(t *testing.T) { |
|
// 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) |
|
tc := timerChild.(*timerCtx) |
|
pc.mu.Lock() |
|
if len(pc.children) != 2 || !pc.children[cc] || !pc.children[tc] { |
|
t.Errorf("bad linkage: pc.children = %v, want %v and %v", |
|
pc.children, cc, tc) |
|
} |
|
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(tc.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 TestChildFinishesFirst(t *testing.T) { |
|
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 || !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, wait time.Duration, t *testing.T) { |
|
select { |
|
case <-time.After(wait): |
|
t.Fatalf("context should have timed out") |
|
case <-c.Done(): |
|
} |
|
if e := c.Err(); e != DeadlineExceeded { |
|
t.Errorf("c.Err() == %v want %v", e, DeadlineExceeded) |
|
} |
|
} |
|
|
|
func TestDeadline(t *testing.T) { |
|
t.Parallel() |
|
const timeUnit = 500 * time.Millisecond |
|
c, _ := WithDeadline(Background(), time.Now().Add(1*timeUnit)) |
|
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, 2*timeUnit, t) |
|
|
|
c, _ = WithDeadline(Background(), time.Now().Add(1*timeUnit)) |
|
o := otherContext{c} |
|
testDeadline(o, 2*timeUnit, t) |
|
|
|
c, _ = WithDeadline(Background(), time.Now().Add(1*timeUnit)) |
|
o = otherContext{c} |
|
c, _ = WithDeadline(o, time.Now().Add(3*timeUnit)) |
|
testDeadline(c, 2*timeUnit, t) |
|
} |
|
|
|
func TestTimeout(t *testing.T) { |
|
t.Parallel() |
|
const timeUnit = 500 * time.Millisecond |
|
c, _ := WithTimeout(Background(), 1*timeUnit) |
|
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, 2*timeUnit, t) |
|
|
|
c, _ = WithTimeout(Background(), 1*timeUnit) |
|
o := otherContext{c} |
|
testDeadline(o, 2*timeUnit, t) |
|
|
|
c, _ = WithTimeout(Background(), 1*timeUnit) |
|
o = otherContext{c} |
|
c, _ = WithTimeout(o, 3*timeUnit) |
|
testDeadline(c, 2*timeUnit, t) |
|
} |
|
|
|
func TestCanceledTimeout(t *testing.T) { |
|
t.Parallel() |
|
const timeUnit = 500 * time.Millisecond |
|
c, _ := WithTimeout(Background(), 2*timeUnit) |
|
o := otherContext{c} |
|
c, cancel := WithTimeout(o, 4*timeUnit) |
|
cancel() |
|
time.Sleep(1 * timeUnit) // 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 TestValues(t *testing.T) { |
|
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 TestAllocs(t *testing.T) { |
|
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: 16, |
|
}, |
|
{ |
|
desc: "WithCancel(bg)", |
|
f: func() { |
|
c, cancel := WithCancel(bg) |
|
cancel() |
|
<-c.Done() |
|
}, |
|
limit: 5, |
|
gccgoLimit: 8, |
|
}, |
|
{ |
|
desc: "WithTimeout(bg, 100*time.Millisecond)", |
|
f: func() { |
|
c, cancel := WithTimeout(bg, 100*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 |
|
} |
|
if n := testing.AllocsPerRun(100, test.f); n > limit { |
|
t.Errorf("%s allocs = %f want %d", test.desc, n, int(limit)) |
|
} |
|
} |
|
} |
|
|
|
func TestSimultaneousCancels(t *testing.T) { |
|
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 TestInterlockedCancels(t *testing.T) { |
|
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 TestLayersCancel(t *testing.T) { |
|
testLayers(t, time.Now().UnixNano(), false) |
|
} |
|
|
|
func TestLayersTimeout(t *testing.T) { |
|
testLayers(t, time.Now().UnixNano(), true) |
|
} |
|
|
|
func testLayers(t *testing.T, 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 + 100*time.Millisecond): |
|
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 TestCancelRemoves(t *testing.T) { |
|
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 cancelling 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 cancelling WithTimeout child", ctx, 0) |
|
}
|
|
|