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 // skip - the test was skipped or the package contained no tests 52 // 53 // The Package field, if present, specifies the package being tested. 54 // When the go command runs parallel tests in -json mode, events from 55 // different tests are interlaced; the Package field allows readers to 56 // separate them. 57 // 58 // The Test field, if present, specifies the test, example, or benchmark 59 // function that caused the event. Events for the overall package test 60 // do not set Test. 61 // 62 // The Elapsed field is set for "pass" and "fail" events. It gives the time 63 // elapsed for the specific test or the overall package test that passed or failed. 64 // 65 // The Output field is set for Action == "output" and is a portion of the test's output 66 // (standard output and standard error merged together). The output is 67 // unmodified except that invalid UTF-8 output from a test is coerced 68 // into valid UTF-8 by use of replacement characters. With that one exception, 69 // the concatenation of the Output fields of all output events is the exact 70 // output of the test execution. 71 // 72 // When a benchmark runs, it typically produces a single line of output 73 // giving timing results. That line is reported in an event with Action == "output" 74 // and no Test field. If a benchmark logs output or reports a failure 75 // (for example, by using b.Log or b.Error), that extra output is reported 76 // as a sequence of events with Test set to the benchmark name, terminated 77 // by a final event with Action == "bench" or "fail". 78 // Benchmarks have no events with Action == "run", "pause", or "cont". 79 // 80 package main 81 82 import ( 83 "flag" 84 "fmt" 85 "io" 86 "os" 87 "os/exec" 88 89 "cmd/internal/test2json" 90 ) 91 92 var ( 93 flagP = flag.String("p", "", "report `pkg` as the package being tested in each event") 94 flagT = flag.Bool("t", false, "include timestamps in events") 95 ) 96 97 func usage() { 98 fmt.Fprintf(os.Stderr, "usage: go tool test2json [-p pkg] [-t] [./pkg.test -test.v]\n") 99 os.Exit(2) 100 } 101 102 func main() { 103 flag.Usage = usage 104 flag.Parse() 105 106 var mode test2json.Mode 107 if *flagT { 108 mode |= test2json.Timestamp 109 } 110 c := test2json.NewConverter(os.Stdout, *flagP, mode) 111 defer c.Close() 112 113 if flag.NArg() == 0 { 114 io.Copy(c, os.Stdin) 115 } else { 116 args := flag.Args() 117 cmd := exec.Command(args[0], args[1:]...) 118 w := &countWriter{0, c} 119 cmd.Stdout = w 120 cmd.Stderr = w 121 if err := cmd.Run(); err != nil { 122 if w.n > 0 { 123 // Assume command printed why it failed. 124 } else { 125 fmt.Fprintf(c, "test2json: %v\n", err) 126 } 127 c.Close() 128 os.Exit(1) 129 } 130 } 131 } 132 133 type countWriter struct { 134 n int64 135 w io.Writer 136 } 137 138 func (w *countWriter) Write(b []byte) (int, error) { 139 w.n += int64(len(b)) 140 return w.w.Write(b) 141 } 142