fix: determine duplicate function precedence based on extension

[khendrikse]

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Summary

This again implements function precedence based on extension by reversing the functions array so it behaves similar to how production works. I also had to reverse the way our sourcedirectories are passed.

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[github-actions]

📊 Benchmark results

Comparing with 17605fc

Package size: 313 MB

⬆️ 0.00% increase vs. 17605fc

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• T-30 (618a41e): 264 MB
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• T (current commit): 313 MB

[eduardoboucas]

Hmm, this feels unrelated to the extension precedence. Is this a separate problem you've identified?

[khendrikse]

It is actually related. In zip-it-and-ship-it we have defined that the rightmost directory takes precedence. Since me reversing the array in this PR is mimicking ZISI behavior, it meant that we had to also use that same logic here in the CLI.

[eduardoboucas]

But we're reversing the array of the functions that come out, not the list of directories going in?

(Sorry if I'm missing the point.)

[khendrikse]

No worries! I'll try to explain it better.

Previously:

In the CLI we were passing the following to ZISI:
directories: [user-func-dir, internal-func-dir]

This meant that zisi returns a list of functions with the following precedence:

• user-func-dir/hello.ts
• user-func-dir/hello.js
• internal-func-dir/hello.js

This is because ZISI will let functions from the rightmost directory take precedence. (fun fact: we pass the internal folder first in netlify/build as well)

That wasn't a problem before in the CLI, as we'd register the first function we'd encounter (in this case user-func-dir/hello.ts), making the user function take precedence, just like we do in netlify/build.

Currently

To make sure we get the same precedence as ZISI passes on to us, I reversed the functions array we got from ZISI before we register functions. But to also make sure that user functions take precedence like they did before, and like they do because of the way we pass the internal-func folder first in netlify/build, I also had to change the way we pass the sourcedirectories.

Otherwise we'd first register the internal-func-dir/hello.js