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// Copyright (c) 2016 Uber Technologies, Inc.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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// Package exit provides stubs so that unit tests can exercise code that calls
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// os.Exit(1).
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package exit
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import "os"
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var _exit = os.Exit
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// With terminates the process by calling os.Exit(code). If the package is
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// stubbed, it instead records a call in the testing spy.
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func With(code int) {
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	_exit(code)
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}
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// A StubbedExit is a testing fake for os.Exit.
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type StubbedExit struct {
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	Exited bool
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	Code   int
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	prev   func(code int)
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}
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// Stub substitutes a fake for the call to os.Exit(1).
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func Stub() *StubbedExit {
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	s := &StubbedExit{prev: _exit}
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	_exit = s.exit
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	return s
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}
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// WithStub runs the supplied function with Exit stubbed. It returns the stub
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// used, so that users can test whether the process would have crashed.
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func WithStub(f func()) *StubbedExit {
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	s := Stub()
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	defer s.Unstub()
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	f()
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	return s
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}
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// Unstub restores the previous exit function.
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func (se *StubbedExit) Unstub() {
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	_exit = se.prev
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}
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func (se *StubbedExit) exit(code int) {
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	se.Exited = true
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	se.Code = code
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}
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