istio

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// Copyright Istio Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//     http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package test
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import (
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	"errors"
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	"fmt"
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	"os"
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	"runtime"
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	"sync"
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	"testing"
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	"istio.io/istio/pkg/log"
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)
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var (
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	_ Failer = &testing.T{}
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	_ Failer = &testing.B{}
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	_ Failer = &errorWrapper{}
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)
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// Failer is an interface to be provided to test functions of the form XXXOrFail. This is a
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// substitute for testing.TB, which cannot be implemented outside of the testing
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// package.
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type Failer interface {
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	Fail()
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	FailNow()
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	Fatal(args ...any)
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	Fatalf(format string, args ...any)
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	Log(args ...any)
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	Logf(format string, args ...any)
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	TempDir() string
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	Helper()
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	Cleanup(func())
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	Skip(args ...any)
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}
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// Fuzzer abstracts *testing.F
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type Fuzzer interface {
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	Fuzz(ff any)
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	Add(args ...any)
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}
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// errorWrapper is a Failer that can be used to just extract an `error`. This allows mixing
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// functions that take in a Failer and those that take an error.
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// The function must be called within a goroutine, or calls to Fatal will try to terminate the outer
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// test context, which will cause the test to panic. The Wrap function handles this automatically
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type errorWrapper struct {
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	mu      sync.RWMutex
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	failed  error
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	cleanup func()
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}
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// Wrap executes a function with a fake Failer, and returns an error if the test failed. This allows
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// calling functions that take a Failer and using them with functions that expect an error, or
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// allowing calling functions that would cause a test to immediately fail to instead return an error.
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// Wrap handles Cleanup() and short-circuiting of Fatal() just like the real testing.T.
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func Wrap(f func(t Failer)) error {
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	done := make(chan struct{})
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	w := &errorWrapper{}
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	go func() {
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		defer close(done)
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		f(w)
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	}()
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	<-done
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	return w.ToErrorCleanup()
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}
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// ToErrorCleanup returns any errors encountered and executes any cleanup actions
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func (e *errorWrapper) ToErrorCleanup() error {
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	e.mu.RLock()
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	defer e.mu.RUnlock()
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	if e.cleanup != nil {
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		e.cleanup()
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	}
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	return e.failed
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}
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func (e *errorWrapper) Fail() {
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	e.Fatal("fail called")
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}
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func (e *errorWrapper) FailNow() {
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	e.Fatal("fail now called")
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}
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func (e *errorWrapper) Fatal(args ...any) {
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	e.mu.Lock()
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	defer e.mu.Unlock()
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	if e.failed == nil {
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		e.failed = errors.New(fmt.Sprint(args...))
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	}
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	runtime.Goexit()
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}
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func (e *errorWrapper) Fatalf(format string, args ...any) {
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	e.Fatal(fmt.Sprintf(format, args...))
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}
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func (e *errorWrapper) Helper() {
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}
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func (e *errorWrapper) Skip(args ...any) {
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	e.Fatal(args...)
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}
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func (e *errorWrapper) Cleanup(f func()) {
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	e.mu.Lock()
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	defer e.mu.Unlock()
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	oldCleanup := e.cleanup
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	e.cleanup = func() {
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		if oldCleanup != nil {
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			defer func() {
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				oldCleanup()
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			}()
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		}
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		f()
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	}
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}
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func (e *errorWrapper) Log(args ...any) {
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	log.Info(fmt.Sprint(args...))
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}
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func (e *errorWrapper) Logf(format string, args ...any) {
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	log.Infof(format, args...)
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}
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func (e *errorWrapper) TempDir() string {
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	tempDir, err := os.MkdirTemp("", "test")
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	if err == nil {
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		e.Cleanup(func() {
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			os.RemoveAll(tempDir)
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		})
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	}
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	return tempDir
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}
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