golden - package defines test helper for working with golden files

Golden files contain expected values within your tests. They are useful when you want to check more complex outputs. This package makes it easy to Save and Load such files within the testdata directory.

Simplest example

func TestMe(t *testing.T) {
    got := doSomething()
    golden.Assert(t, got)
}

The golden file for above test is saved in testdata/package.TestMe and an entry is added to testdata/golden.files which keeps track of used files. If you eg. rename a test the golden file will be saved under a new name.

Keep golden.files under revision control to quickly spot which files are no longer used.

To update the golden files use

go test -args -update-golden

Article at 7de.se/golden