fix(configuration): deprecate trailingComma in favor of trailingCommas

[Sec-ant]

Summary

Attempt to address this #1948 (comment).

• I updated all the tests to use the new option name (plural form trailingCommas) instead of the old one, so there're many snapshot updates.
• The old name is kept for backward compatibility. Fully removal requires a major version bump.
• I found there're some bugs in properly handling the option indentSize. For example, when --indent-size and --indent-width are both provided, the code lacks the logic to prioritize --indent-width over --indent-size. I also fixed them in this PR.
• I created a helper function for the JSON analyzer to conveniently match a JSON member name node against a path. For example, I can use it to test whether a "trailingComma" node matches the path ["javascript", "formatter", "trailingComma"]. I also updated the indentSize migration rule to use this function.
• Some tests still use the option name indentSize, I updated them to use indentWidth.
• I removed the Indent size row from the rage output.
• Overall, the deprecation logic follows what we did for indentSize.

Test Plan

I added test cases to ensure the old name is still functional in CLI mode, and both of the old and new names are valid configurations.

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[codspeed-hq]

CodSpeed Performance Report

Merging #2492 will not alter performance

_{Comparing Sec-ant:fix/use-trailing-commas (eb4cfc2) with main (99d5f63)}

Summary

✅ 97 untouched benchmarks

[ematipico]

@Sec-ant sorry, I missed that you wanted to know how to deprecate an option.

Overall it looks good. To create a warning, we usually do it via migration. Here's an example of formatter.indentSize: https://github.com/biomejs/biome/blob/main/crates/biome_migrate/src/analyzers/indent_size.rs

[Sec-ant]

@Sec-ant sorry, I missed that you wanted to know how to deprecate an option.

Don't be sorry, I was planning to dig a little deeper, and thanks for the tips. But unfortunately I'm a little occupied these days. Still trying to figure out a way to better balance the time here and in my real life.

[ematipico]

What's left for this PR to land? Happy to help

[Sec-ant]

What's left for this PR to land? Happy to help

TLDR, this PR now is not backward compatible, because I changed all the test cases to use trailingCommas instead of trailingComma, so all of them will pass. But this will be a breaking change for all the existing code.

When I first created this PR I was trying to find a solution to map both the trailingComma and trailingCommas inputs to a single representation in the internal structure. That's what I did for the bpaf command line args parsing (--trailing-comma is just an alias of --trailing-commas, and with the help of @pacak, I was also able to add some custom messages to indicate its deprecation). But I encountered problems on parsing the configuration JSON in this way. I think that's because we have our own deserialization based on serde that emits some further diagnostics (?), and that's where I have the problem implementing the similar alias mechanism like what I did with the command line parsing.

From what you suggested on how we handled formatter.indentSize, I think I was doing it in a wrong way: It seems that we need to keep both trailingComma and trailingCommas in the internal structure. And since then I haven't found enough large block of time to debug it, sorry about that.

[ematipico]

So, configuration wise (biome.json and CLI), we will create a new field/option, the one that you want to create.

Then, when we do the deserialization to WorkspaceSettings, we will map this new value to the one that we currently have.

Workspace settings is an internal type, this means that we can rename it without repercussions.

Sure, users might have the two options at the same time, and we could create an error/warning, but we can do it later.