1 // +build !nacl 2 // run 3 4 // Copyright 2017 The Go Authors. All rights reserved. 5 // Use of this source code is governed by a BSD-style 6 // license that can be found in the LICENSE file. 7 8 // ensure that panic(x) where x is a numeric type displays a readable number 9 package main 10 11 import ( 12 "bytes" 13 "fmt" 14 "io/ioutil" 15 "log" 16 "os" 17 "os/exec" 18 "path/filepath" 19 ) 20 21 const fn = ` 22 package main 23 24 import "errors" 25 type S struct { 26 27 } 28 func (s S) String() string { 29 return "s-stringer" 30 } 31 func main() { 32 _ = errors.New 33 panic(%s(%s)) 34 } 35 ` 36 37 func main() { 38 tempDir, err := ioutil.TempDir("", "") 39 if err != nil { 40 log.Fatal(err) 41 } 42 defer os.RemoveAll(tempDir) 43 tmpFile := filepath.Join(tempDir, "tmp.go") 44 45 for _, tc := range []struct { 46 Type string 47 Input string 48 Expect string 49 }{{"", "nil", "panic: nil"}, 50 {"errors.New", `"test"`, "panic: test"}, 51 {"S", "S{}", "panic: s-stringer"}, 52 {"byte", "8", "panic: 8"}, 53 {"rune", "8", "panic: 8"}, 54 {"int", "8", "panic: 8"}, 55 {"int8", "8", "panic: 8"}, 56 {"int16", "8", "panic: 8"}, 57 {"int32", "8", "panic: 8"}, 58 {"int64", "8", "panic: 8"}, 59 {"uint", "8", "panic: 8"}, 60 {"uint8", "8", "panic: 8"}, 61 {"uint16", "8", "panic: 8"}, 62 {"uint32", "8", "panic: 8"}, 63 {"uint64", "8", "panic: 8"}, 64 {"uintptr", "8", "panic: 8"}, 65 {"bool", "true", "panic: true"}, 66 {"complex64", "8 + 16i", "panic: (+8.000000e+000+1.600000e+001i)"}, 67 {"complex128", "8+16i", "panic: (+8.000000e+000+1.600000e+001i)"}, 68 {"string", `"test"`, "panic: test"}} { 69 70 b := bytes.Buffer{} 71 fmt.Fprintf(&b, fn, tc.Type, tc.Input) 72 73 err = ioutil.WriteFile(tmpFile, b.Bytes(), 0644) 74 if err != nil { 75 log.Fatal(err) 76 } 77 78 cmd := exec.Command("go", "run", tmpFile) 79 var buf bytes.Buffer 80 cmd.Stdout = &buf 81 cmd.Stderr = &buf 82 cmd.Env = os.Environ() 83 cmd.Run() // ignore err as we expect a panic 84 85 out := buf.Bytes() 86 panicIdx := bytes.Index(out, []byte("panic: ")) 87 if panicIdx == -1 { 88 log.Fatalf("expected a panic in output for %s, got: %s", tc.Type, out) 89 } 90 eolIdx := bytes.IndexByte(out[panicIdx:], '\n') + panicIdx 91 if panicIdx == -1 { 92 log.Fatalf("expected a newline in output for %s after the panic, got: %s", tc.Type, out) 93 } 94 out = out[0:eolIdx] 95 if string(out) != tc.Expect { 96 log.Fatalf("expected '%s' for panic(%s(%s)), got %s", tc.Expect, tc.Type, tc.Input, out) 97 } 98 } 99 } 100
