[Bug]: @babel/traverse v7.17.10 broken `this` scope with dead code elimination plugin about minify HOT 5 OPEN

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from minify.

It seems that @babel/traverse v7.17.10 has only this one commit which is probably the cause for this - or then the minify plugin needs to be updated somehow to accommodate for these changes (I'm not a Babel developer so I have no clue). FYI @JLHwung

from minify.

Thanks for the report. This issue should be fixed in the minify plugin.

Before v7.17.10 Babel does not report this as a pure expression, so dce will not try to remove _this = this. However, after 7.17.0 we should check whether the original non-arrow scope is same with the replacement non-arrow scope. If they are same, we can safely replace _this by this, otherwise we should bail.

from minify.

Note that deadcode also suffers from #981, so I'd recommend simply disabling it (along with simplify for #999 and builtIns for #904 if you run into it).

Unfortunately this project appears to be unmaintained (the last commit was in August of 2020), so looking into other minifiers might also not be a bad idea.

from minify.

Unfortunately this project appears to be unmaintained (the last commit was in August of 2020), so looking into other minifiers might also not be a bad idea.

This is quite bad. We have a build pipeline that relies on minify-replace and minify-dead-code-elimination working in tandem to have different compile targets. It's quite critical to us so just disabling deadcode elimination is not an option. I'll look into other options but basically this means that we'll need to stick to an older Babel version until we can work out a replacement.

from minify.