1 // Copyright 2017 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 // Test2json converts go test output to a machine-readable JSON stream. 6 // 7 // Usage: 8 // 9 // go tool test2json [-p pkg] [-t] [./pkg.test -test.v] 10 // 11 // Test2json runs the given test command and converts its output to JSON; 12 // with no command specified, test2json expects test output on standard input. 13 // It writes a corresponding stream of JSON events to standard output. 14 // There is no unnecessary input or output buffering, so that 15 // the JSON stream can be read for live updates of test status. 16 // 17 // The -p flag sets the package reported in each test event. 18 // 19 // The -t flag requests that time stamps be added to each test event. 20 // 21 // Note that test2json is only intended for converting a single test 22 // binary's output. To convert the output of a "go test" command, 23 // use "go test -json" instead of invoking test2json directly. 24 // 25 // Output Format 26 // 27 // The JSON stream is a newline-separated sequence of TestEvent objects 28 // corresponding to the Go struct: 29 // 30 // type TestEvent struct { 31 // Time time.Time // encodes as an RFC3339-format string 32 // Action string 33 // Package string 34 // Test string 35 // Elapsed float64 // seconds 36 // Output string 37 // } 38 // 39 // The Time field holds the time the event happened. 40 // It is conventionally omitted for cached test results. 41 // 42 // The Action field is one of a fixed set of action descriptions: 43 // 44 // run - the test has started running 45 // pause - the test has been paused 46 // cont - the test has continued running 47 // pass - the test passed 48 // bench - the benchmark printed log output but did not fail 49 // fail - the test or benchmark failed 50 // output - the test printed output 51 // 52 // The Package field, if present, specifies the package being tested. 53 // When the go command runs parallel tests in -json mode, events from 54 // different tests are interlaced; the Package field allows readers to 55 // separate them. 56 // 57 // The Test field, if present, specifies the test, example, or benchmark 58 // function that caused the event. Events for the overall package test 59 // do not set Test. 60 // 61 // The Elapsed field is set for "pass" and "fail" events. It gives the time 62 // elapsed for the specific test or the overall package test that passed or failed. 63 // 64 // The Output field is set for Action == "output" and is a portion of the test's output 65 // (standard output and standard error merged together). The output is 66 // unmodified except that invalid UTF-8 output from a test is coerced 67 // into valid UTF-8 by use of replacement characters. With that one exception, 68 // the concatenation of the Output fields of all output events is the exact 69 // output of the test execution. 70 // 71 // When a benchmark runs, it typically produces a single line of output 72 // giving timing results. That line is reported in an event with Action == "output" 73 // and no Test field. If a benchmark logs output or reports a failure 74 // (for example, by using b.Log or b.Error), that extra output is reported 75 // as a sequence of events with Test set to the benchmark name, terminated 76 // by a final event with Action == "bench" or "fail". 77 // Benchmarks have no events with Action == "run", "pause", or "cont". 78 // 79 package main 80 81 import ( 82 "flag" 83 "fmt" 84 "io" 85 "os" 86 "os/exec" 87 88 "cmd/internal/test2json" 89 ) 90 91 var ( 92 flagP = flag.String("p", "", "report `pkg` as the package being tested in each event") 93 flagT = flag.Bool("t", false, "include timestamps in events") 94 ) 95 96 func usage() { 97 fmt.Fprintf(os.Stderr, "usage: go tool test2json [-p pkg] [-t] [./pkg.test -test.v]\n") 98 os.Exit(2) 99 } 100 101 func main() { 102 flag.Usage = usage 103 flag.Parse() 104 105 var mode test2json.Mode 106 if *flagT { 107 mode |= test2json.Timestamp 108 } 109 c := test2json.NewConverter(os.Stdout, *flagP, mode) 110 defer c.Close() 111 112 if flag.NArg() == 0 { 113 io.Copy(c, os.Stdin) 114 } else { 115 args := flag.Args() 116 cmd := exec.Command(args[0], args[1:]...) 117 w := &countWriter{0, c} 118 cmd.Stdout = w 119 cmd.Stderr = w 120 if err := cmd.Run(); err != nil { 121 if w.n > 0 { 122 // Assume command printed why it failed. 123 } else { 124 fmt.Fprintf(c, "test2json: %v\n", err) 125 } 126 c.Close() 127 os.Exit(1) 128 } 129 } 130 } 131 132 type countWriter struct { 133 n int64 134 w io.Writer 135 } 136 137 func (w *countWriter) Write(b []byte) (int, error) { 138 w.n += int64(len(b)) 139 return w.w.Write(b) 140 } 141