test2json

Documentation

Overview

Test2json converts go test output to a machine-readable JSON stream.

Usage:

go test ... | go tool test2json [-p pkg] [-t]
./test.out 2>&1 | go tool test2json [-p pkg] [-t]

Test2json expects to read go test output from 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.

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
	Event   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 Event field is one of a fixed set of event descriptions:

run    - the test has started running
pause  - the test has been paused
cont   - the test has continued running
pass   - the test passed
fail   - the test failed
output - the test printed output

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 or 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 Event == "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.