1 // Copyright (c) 2016 Uber Technologies, Inc. 2 // 3 // Permission is hereby granted, free of charge, to any person obtaining a copy 4 // of this software and associated documentation files (the "Software"), to deal 5 // in the Software without restriction, including without limitation the rights 6 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 7 // copies of the Software, and to permit persons to whom the Software is 8 // furnished to do so, subject to the following conditions: 9 // 10 // The above copyright notice and this permission notice shall be included in 11 // all copies or substantial portions of the Software. 12 // 13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 14 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 15 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 16 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 17 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 18 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 19 // THE SOFTWARE. 20 21 // Package exit provides stubs so that unit tests can exercise code that calls 22 // os.Exit(1). 23 package exit 24 25 import "os" 26 27 var _exit = os.Exit 28 29 // With terminates the process by calling os.Exit(code). If the package is 30 // stubbed, it instead records a call in the testing spy. 31 func With(code int) { 32 _exit(code) 33 } 34 35 // A StubbedExit is a testing fake for os.Exit. 36 type StubbedExit struct { 37 Exited bool 38 Code int 39 prev func(code int) 40 } 41 42 // Stub substitutes a fake for the call to os.Exit(1). 43 func Stub() *StubbedExit { 44 s := &StubbedExit{prev: _exit} 45 _exit = s.exit 46 return s 47 } 48 49 // WithStub runs the supplied function with Exit stubbed. It returns the stub 50 // used, so that users can test whether the process would have crashed. 51 func WithStub(f func()) *StubbedExit { 52 s := Stub() 53 defer s.Unstub() 54 f() 55 return s 56 } 57 58 // Unstub restores the previous exit function. 59 func (se *StubbedExit) Unstub() { 60 _exit = se.prev 61 } 62 63 func (se *StubbedExit) exit(code int) { 64 se.Exited = true 65 se.Code = code 66 } 67