aboutsummaryrefslogtreecommitdiff
path: root/src/cmd/test2json/main.go
blob: 14626974989834e4118ac9856b04bad6db1dd3d4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Test2json converts go test output to a machine-readable JSON stream.
//
// Usage:
//
//	go tool test2json [-p pkg] [-t] [./pkg.test -test.v]
//
// Test2json runs the given test command and converts its output to JSON;
// with no command specified, test2json expects test output on standard input.
// It writes a corresponding stream of JSON events to standard output.
// There is no unnecessary input or output buffering, so that
// the JSON stream can be read for “live updates” of test status.
//
// The -p flag sets the package reported in each test event.
//
// The -t flag requests that time stamps be added to each test event.
//
// Note that test2json is only intended for converting a single test
// binary's output. To convert the output of a "go test" command,
// use "go test -json" instead of invoking test2json directly.
//
// Output Format
//
// The JSON stream is a newline-separated sequence of TestEvent objects
// corresponding to the Go struct:
//
//	type TestEvent struct {
//		Time    time.Time // encodes as an RFC3339-format string
//		Action  string
//		Package string
//		Test    string
//		Elapsed float64 // seconds
//		Output  string
//	}
//
// The Time field holds the time the event happened.
// It is conventionally omitted for cached test results.
//
// The Action field is one of a fixed set of action descriptions:
//
//	run    - the test has started running
//	pause  - the test has been paused
//	cont   - the test has continued running
//	pass   - the test passed
//	bench  - the benchmark printed log output but did not fail
//	fail   - the test or benchmark failed
//	output - the test printed output
//	skip   - the test was skipped or the package contained no tests
//
// The Package field, if present, specifies the package being tested.
// When the go command runs parallel tests in -json mode, events from
// different tests are interlaced; the Package field allows readers to
// separate them.
//
// The Test field, if present, specifies the test, example, or benchmark
// function that caused the event. Events for the overall package test
// do not set Test.
//
// The Elapsed field is set for "pass" and "fail" events. It gives the time
// elapsed for the specific test or the overall package test that passed or failed.
//
// The Output field is set for Action == "output" and is a portion of the test's output
// (standard output and standard error merged together). The output is
// unmodified except that invalid UTF-8 output from a test is coerced
// into valid UTF-8 by use of replacement characters. With that one exception,
// the concatenation of the Output fields of all output events is the exact
// output of the test execution.
//
// When a benchmark runs, it typically produces a single line of output
// giving timing results. That line is reported in an event with Action == "output"
// and no Test field. If a benchmark logs output or reports a failure
// (for example, by using b.Log or b.Error), that extra output is reported
// as a sequence of events with Test set to the benchmark name, terminated
// by a final event with Action == "bench" or "fail".
// Benchmarks have no events with Action == "run", "pause", or "cont".
//
package main

import (
	"flag"
	"fmt"
	exec "internal/execabs"
	"io"
	"os"

	"cmd/internal/test2json"
)

var (
	flagP = flag.String("p", "", "report `pkg` as the package being tested in each event")
	flagT = flag.Bool("t", false, "include timestamps in events")
)

func usage() {
	fmt.Fprintf(os.Stderr, "usage: go tool test2json [-p pkg] [-t] [./pkg.test -test.v]\n")
	os.Exit(2)
}

func main() {
	flag.Usage = usage
	flag.Parse()

	var mode test2json.Mode
	if *flagT {
		mode |= test2json.Timestamp
	}
	c := test2json.NewConverter(os.Stdout, *flagP, mode)
	defer c.Close()

	if flag.NArg() == 0 {
		io.Copy(c, os.Stdin)
	} else {
		args := flag.Args()
		cmd := exec.Command(args[0], args[1:]...)
		w := &countWriter{0, c}
		cmd.Stdout = w
		cmd.Stderr = w
		err := cmd.Run()
		if err != nil {
			if w.n > 0 {
				// Assume command printed why it failed.
			} else {
				fmt.Fprintf(c, "test2json: %v\n", err)
			}
		}
		c.Exited(err)
		if err != nil {
			c.Close()
			os.Exit(1)
		}
	}
}

type countWriter struct {
	n int64
	w io.Writer
}

func (w *countWriter) Write(b []byte) (int, error) {
	w.n += int64(len(b))
	return w.w.Write(b)
}