feat(cli): suggest matching commands

[jamesgeorge007]

closes #1762

[coveralls]

Coverage remained the same at 100.0% when pulling 9d1b221 on jamesgeorge007:feat/suggest-commands into d17e6a8 on mozilla:master.

[Rob--W]

Thanks for the feature request and patch. Could you add a unit test to the following file?
https://github.com/mozilla/web-ext/blob/3c850ae49c59e6d56d7e6f189a873bb02ae30012/tests/unit/test.program.js

[Rob--W]

As you can see from the CI build output, the new test is failing: https://travis-ci.org/mozilla/web-ext/jobs/615041182

Please update the test to make sure that it passes.

[jamesgeorge007]

@Rob--W can you give me a better picture regarding how it should be refactored as per the context?

[Rob--W]

I think that the relevant output is not an instance of UsageError. Try checking the program's output instead, like this:

web-ext/tests/unit/test.program.js

Lines 103 to 105 in f9929da

	.catch((error) => {
	assert.match(error.message, /This command does not take any arguments/);
	});

[Rob--W]

Could you revert the change to package-lock.json? The audit failure has been fixed on master, and if you rebase your patch on master, then that failure should go away.

The build still fails with the latest version of your patch. I took a closer look, and see why. Your unit test uses the Program constructor to run the program. But the recommendCommands() configuration is only defined in the main function. To test the desired behavior, you need to run the program instead of calling the constructor.

Here are examples:

• https://github.com/mozilla/web-ext/blob/7c0f282db5ea6bd44aaa97b19701b64f84893655/tests/functional/test.cli.nocommand.js
• https://github.com/mozilla/web-ext/blob/961da0c27cea875484338fcb0801d10229672df1/tests/functional/test.cli.run.js

Add a new test, e.g. with the file name tests/functional/test.typo.run.js

[Rob--W]

Have you run the tests locally? The test is failing because the assert object has not been imported.

And the linting fails because the test imports symbols that it does not use.

Remove unused imports and import `assert to resolve these errors.

[Rob--W]

Thanks for the feature request and patch!