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// Copyright 2019 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package android
import (
"testing"
"time"
)
func TestOncePer_Once(t *testing.T) {
once := OncePer{}
key := NewOnceKey("key")
a := once.Once(key, func() interface{} { return "a" }).(string)
b := once.Once(key, func() interface{} { return "b" }).(string)
if a != "a" {
t.Errorf(`first call to Once should return "a": %q`, a)
}
if b != "a" {
t.Errorf(`second call to Once with the same key should return "a": %q`, b)
}
}
func TestOncePer_Once_wait(t *testing.T) {
once := OncePer{}
key := NewOnceKey("key")
ch := make(chan bool)
go once.Once(key, func() interface{} { close(ch); time.Sleep(100 * time.Millisecond); return "foo" })
<-ch
a := once.Once(key, func() interface{} { return "bar" }).(string)
if a != "foo" {
t.Errorf("expect %q, got %q", "foo", a)
}
}
func TestOncePer_Get(t *testing.T) {
once := OncePer{}
key := NewOnceKey("key")
a := once.Once(key, func() interface{} { return "a" }).(string)
b := once.Get(key).(string)
if a != "a" {
t.Errorf(`first call to Once should return "a": %q`, a)
}
if b != "a" {
t.Errorf(`Get with the same key should return "a": %q`, b)
}
}
func TestOncePer_Get_panic(t *testing.T) {
once := OncePer{}
key := NewOnceKey("key")
defer func() {
p := recover()
if p == nil {
t.Error("call to Get for unused key should panic")
}
}()
once.Get(key)
}
func TestOncePer_Get_wait(t *testing.T) {
once := OncePer{}
key := NewOnceKey("key")
ch := make(chan bool)
go once.Once(key, func() interface{} { close(ch); time.Sleep(100 * time.Millisecond); return "foo" })
<-ch
a := once.Get(key).(string)
if a != "foo" {
t.Errorf("expect %q, got %q", "foo", a)
}
}
func TestOncePer_OnceStringSlice(t *testing.T) {
once := OncePer{}
key := NewOnceKey("key")
a := once.OnceStringSlice(key, func() []string { return []string{"a"} })
b := once.OnceStringSlice(key, func() []string { return []string{"a"} })
if a[0] != "a" {
t.Errorf(`first call to OnceStringSlice should return ["a"]: %q`, a)
}
if b[0] != "a" {
t.Errorf(`second call to OnceStringSlice with the same key should return ["a"]: %q`, b)
}
}
func TestOncePer_Once2StringSlice(t *testing.T) {
once := OncePer{}
key := NewOnceKey("key")
a, b := once.Once2StringSlice(key, func() ([]string, []string) { return []string{"a"}, []string{"b"} })
c, d := once.Once2StringSlice(key, func() ([]string, []string) { return []string{"c"}, []string{"d"} })
if a[0] != "a" || b[0] != "b" {
t.Errorf(`first call to Once2StringSlice should return ["a"], ["b"]: %q, %q`, a, b)
}
if c[0] != "a" || d[0] != "b" {
t.Errorf(`second call to Once2StringSlice with the same key should return ["a"], ["b"]: %q, %q`, c, d)
}
}
func TestNewOnceKey(t *testing.T) {
once := OncePer{}
key1 := NewOnceKey("key")
key2 := NewOnceKey("key")
a := once.Once(key1, func() interface{} { return "a" }).(string)
b := once.Once(key2, func() interface{} { return "b" }).(string)
if a != "a" {
t.Errorf(`first call to Once should return "a": %q`, a)
}
if b != "b" {
t.Errorf(`second call to Once with the NewOnceKey from same string should return "b": %q`, b)
}
}
func TestNewCustomOnceKey(t *testing.T) {
type key struct {
key string
}
once := OncePer{}
key1 := NewCustomOnceKey(key{"key"})
key2 := NewCustomOnceKey(key{"key"})
a := once.Once(key1, func() interface{} { return "a" }).(string)
b := once.Once(key2, func() interface{} { return "b" }).(string)
if a != "a" {
t.Errorf(`first call to Once should return "a": %q`, a)
}
if b != "a" {
t.Errorf(`second call to Once with the NewCustomOnceKey from equal key should return "a": %q`, b)
}
}
func TestOncePerReentrant(t *testing.T) {
once := OncePer{}
key1 := NewOnceKey("key")
key2 := NewOnceKey("key")
a := once.Once(key1, func() interface{} { return once.Once(key2, func() interface{} { return "a" }) })
if a != "a" {
t.Errorf(`reentrant Once should return "a": %q`, a)
}
}
// Test that a recovered panic in a Once function doesn't deadlock
func TestOncePerPanic(t *testing.T) {
once := OncePer{}
key := NewOnceKey("key")
ch := make(chan interface{})
var a interface{}
go func() {
defer func() {
ch <- recover()
}()
a = once.Once(key, func() interface{} {
panic("foo")
})
}()
p := <-ch
if p.(string) != "foo" {
t.Errorf(`expected panic with "foo", got %#v`, p)
}
if a != nil {
t.Errorf(`expected a to be nil, got %#v`, a)
}
// If the call to Once that panicked leaves the key in a bad state this will deadlock
b := once.Once(key, func() interface{} {
return "bar"
})
// The second call to Once should return nil inserted by the first call that panicked.
if b != nil {
t.Errorf(`expected b to be nil, got %#v`, b)
}
}
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