🤖 nodetest

amadan.net/rastrillo/rastrillo/nodetest

Run a Node script from a Go test. Use it for JavaScript that has a Go twin or logic that needs no browser, such as a crypto envelope both languages must open or a date parser.

Node is a development tool here, not a dependency of your app. Anything that needs a real page still belongs in a browser test.

Node

const RequireEnv = "RASTRILLO_TEST_REQUIRE_NODE"

func Node(t testing.TB) string

Node returns the path to node. If there is none on your PATH, it skips the test and names it, so you can see what went unchecked.

Set RASTRILLO_TEST_REQUIRE_NODE on CI. A missing node then fails the test instead of skipping it, so the JavaScript checks cannot disappear without anyone noticing. Rastrillo's own make ci sets it.

Run

type Cmd struct {
	Args    []string
	Dir     string
	Stdin   []byte
	Env     []string
	Timeout time.Duration
}

const DefaultTimeout = 2 * time.Minute

func Run(t testing.TB, c Cmd) []byte

out := nodetest.Run(t, nodetest.Cmd{
	Args: []string{"--test", "js/golden.test.mjs"},
	Env:  []string{"TZ=UTC"},
})

Run runs node with Args and returns what it wrote to stdout. Dir is the working directory; leave it empty for the test's package directory. Stdin is fed to the script. Env adds to the test's environment, so name only what you change, such as TZ=UTC.

If node exits with an error, the test fails with both stdout and stderr. node --test reports failures on stdout, and a crash lands on stderr.

A script that has not finished after Timeout fails the test by name. The default, DefaultTimeout, is two minutes.

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