fix source map stripping issue

[FredKSchott]

Changes

• Makes our "outdated source map" replacer more strict, can no longer be found inside/next to a string
• This is a small incremental improvement over what we have to fix Installing dependency fails with 'Unterminated string constant' error #1115 (and others like it)
• If we still run into issues in the future, we can go more strict and say "we only strip this type of comment if it starts on a new line".

Testing

• Added a test

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[drwpow]

Ok so this doesn’t strip the source map if a string character is right before it?

This works for me. But I wonder if there’s a way to also change this so that it only strips it if it’s literally the last thing in the file (which may or may not end on a newline). This doesn’t have to be on its own line, but I’ve never seen it mid-file before; only at the end.

Something like (pseudocode)

/\/\/#s\*sourceMappingURL=[A-Za-z0-9-/:.]+\n?$/

[FredKSchott]

Ah, unfortunately, I've seen a few mid-file, usually when the package has been pre-bundled in some way. But, there's a chance that esinstall actually caused that, and each individual transform had only one sourceMappingURL comment.

This is enough for now and I don't want a regression unnecessarily, but if there are still bugs after this then let's revisit.

[drwpow]

Ah I thought there was a reason for scanning mid-file. Bug found 🙃 : #1505

[drwpow]

👍🏻

100% never does what you think it will, does it? 😄

[FredKSchott]

haha sadly, no