throw results in an uncovered line

[coreyfarrell]

• Version: v11.7.0
• Platform: Linux lt2 4.19.8-200.fc28.x86_64 Detailed coverage #1 SMP Mon Dec 10 15:43:40 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

function testThrow(doThrow) {
	if (doThrow) {
		throw new Error('test throw');
	}
}

testThrow(true);

Run the above under c8, it reports that line 4 is not covered. Really since line 4 is only a } I think it should not even count, having no else statement means that line is non-significant. IMO significance of lines comment applies to lines 5 and 6 as well, the } of a function does not have any actual code. Line 6 is blank so that should not be counted.

nyc basically works the way I expect, though the function testThrow(doThrow) { line isn't part of the total or covered lines. I don't have a strong opinion about counting / not counting the function declaration as a line.

[bcoe]

see: https://bugs.chromium.org/p/v8/issues/detail?id=8691

[coreyfarrell]

Turns out it's not just throw which does this. The following code does the same thing - the } of the if block cannot be covered.

function testReturn(doReturn) {
	if (doReturn) {
		return;
	}
}

testReturn(true);

[shinnn]

As far as I investigated, with Node.js v11.13.0, the code on both #58 (comment) and #58 (comment) are regarded as 100%-covered by c8.

[coreyfarrell]

@shinnn confirmed, thanks for pointing this out.

[bcoe]

@coreyfarrell @shinnn awesome \o/ glad to see some of these issues being resolved.