Test hangs or times out on some TypeScript compilation errors.

[paulgb]

When I run this test:

import test from 'ava'

test('foobar', async (t) => {
    const foo_1 = foo()
    const foo_2 = foo()
    const foo_3 = foo()
    const foo_4 = foo()
    const foo_5 = foo()
    const foo_6 = foo()
    const foo_7 = foo()
})

Instead of reporting a compilation error, I get this:

  ✖ Timed out while running tests

If I remove one of the declarations, I get the following, as expected:

  Uncaught exception in src/test-spawn.ts

  src/test-spawn.ts(4,19): error TS2304: Cannot find name 'foo'.
  src/test-spawn.ts(5,19): error TS2304: Cannot find name 'foo'.
  src/test-spawn.ts(6,19): error TS2304: Cannot find name 'foo'.
  src/test-spawn.ts(7,19): error TS2304: Cannot find name 'foo'.
  src/test-spawn.ts(8,19): error TS2304: Cannot find name 'foo'.
  src/test-spawn.ts(9,19): error TS2304: Cannot find name 'foo'.
  

  ✖ src/test-spawn.ts exited with a non-zero exit code: 1
  ─

  1 uncaught exception

It seems there's some threshold (maybe the amount of tsc output?) that's causing ava to time out rather than report the error.

This occurs when using the ts-node/register TypeScript approach (https://github.com/avajs/ava/blob/main/docs/recipes/typescript.md#for-packages-without-type-module).

I've created a minimal reproducible example here: https://github.com/paulgb/ava-timeout-issue-repro

[novemberborn]

When you remove one line, the test worker exits with a non-zero exit code. That's what AVA's looking for. The timeout is triggered when there is no activity from the worker.

When I set the timeout to 20 seconds (--timeout 20s) it does fail correctly, albeit after a while.

I'm inclined to say this is something awry with ts-node.

[paulgb]

Thanks @novemberborn.

For what it's worth, I solved the issue by using ts-node/register/transpile-only rather than ts-node/register. That might not be the solution for everyone since it disables the type checks, but I'd rather get a type error than a hard-to-diagnose timeout, and a typescript-aware editor can still catch the type issues.

[vexCoder]

Thanks @novemberborn.

For what it's worth, I solved the issue by using ts-node/register/transpile-only rather than ts-node/register. That might not be the solution for everyone since it disables the type checks, but I'd rather get a type error than a hard-to-diagnose timeout, and a typescript-aware editor can still catch the type issues.

Thank you so much. how did you figure this out?

[paulgb]

I think I got the flag itself from these docs. Aside from that it was just trial and error.

My approach now is for the npm test script to run tsc && ava so that typescript issues are still caught, which feels a bit funny because typescript is making two passes over the code (once to validate the types, and then to run with ts-node), but it does the job.

[novemberborn]

@ava/typescript lets you work with that tsc output, or it can run tsc for you before the tests run.

[download13]

I was having this problem while using typescript ES modules,

Adding nodeArguments: ['--loader=ts-node/esm/transpile-only'] to ava.config.js worked for me.

[liby]

After testing, neither the use of ts-node/register/transpile-only nor @swc-node/register solves the problem, and Timed out while running tests is still seen.

[download13]

Something called TSX just came out. Its like ts-node but only uses esbuild to strip out the types instead of checking them.

I swapped the ava node options to --loader=tsx which worked great. No more silent swallowing of type errors.

[liby]

Is there a repository link? I would like to refer to the configuration

[pc-erin]

@liby I don't have a whole repository, but the config I'm using looks like this:

{
	"ava": {
		"files": [
			"test/*.ts"
		],
		"nodeArguments": [
			"--loader=tsx"
		]
	}
}

The ava property just goes in the bottom of your package.json file as shown in the docs

You also need to install tsx as a devDependency, of course.