`--experimental-test-coverage` cannot be used with `--test`

[piranna]

Version

v20.0.0

Platform

Linux executive 5.19.0-40-generic #41-Ubuntu SMP PREEMPT_DYNAMIC Thu Mar 23 21:39:15 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

Subsystem

test

What steps will reproduce the bug?

Running node --test lookup for tests in the current project folder. When adding the --experimental-test-coverage flag I get the error node: --experimental-test-coverage cannot be used with --test, and if I remove the --test flag and left the --experimental-test-coverage flag alone, it throws me to a REPL without looking for the tests. Only way to run the tests with code coverage is by executing it explicitly with node --experimental-test-coverage test.js, passing test files as arguments.

How often does it reproduce? Is there a required condition?

Always.

What is the expected behavior? Why is that the expected behavior?

When running node --experimental-test-coverage, it should implicitly call --test and look for the test files, or allow to have both --test and --experimental-test-coverage flags in the same command.

What do you see instead?

Error node: --experimental-test-coverage cannot be used with --test, or a REPL if I remove the --test flag.

Additional information

No response

[richardlau]

#47651 mentions it is the first step towards addressing this.

[richardlau]

This is a documented limitation which looks like it's being worked on.

node/doc/api/test.md

Lines 423 to 432 in 7b39e80

	The test runner's code coverage functionality has the following limitations,
	which will be addressed in a future Node.js release:
	* Although coverage data is collected for child processes, this information is
	not included in the coverage report. Because the command line test runner uses
	child processes to execute test files, it cannot be used with
	`--experimental-test-coverage`.
	* Source maps are not supported.
	* Excluding specific files or directories from the coverage report is not
	supported.

[cjihrig]

FWIW, I should have a PR to address this soon - possibly in the next day or so.

[piranna]

#47651 mentions it is the first step towards addressing this.

Thanks for clarifying, subscribed to that PR.

[muturgan]

will it be added in version 18?