fix(formatter): Complete is_complex_type_arguments()

[leaysgur]

Fixes #17275.

At fitst, I just added TSTypeReference after TSMappedType. However it produced another formatting difference (= fails current snapshot tests).

[leaysgur]

• fix(formatter): Complete is_complex_type_arguments() #17353 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

This PR completes the implementation of the is_complex_type_arguments function by adding the previously missing will_break() logic. This allows the formatter to correctly identify complex type arguments in call expressions and apply appropriate formatting.

Key Changes

• Completed the is_complex_type_arguments function by implementing the will_break() check that was previously marked as TODO
• Changed function signatures from &Formatter to &mut Formatter to support the new inspect() method
• Simplified the explicit type matching by removing TSMappedType, which is now handled by the will_break() logic

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
crates/oxc_formatter/src/utils/assignment_like.rs	Completed is_complex_type_arguments implementation with will_break() logic and updated function signatures to accept mutable Formatter references
crates/oxc_formatter/tests/fixtures/ts/assignments/complex-type-arguments.ts	Added test case for TSTypeReference with nested TSTypeLiteral to verify the fix
crates/oxc_formatter/tests/fixtures/ts/assignments/complex-type-arguments.ts.snap	Updated snapshot to include expected formatting output for the new test case

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[codspeed-hq]

CodSpeed Performance Report

Merging #17353 will not alter performance

_{Comparing 12-25-fix_formatter_complete_is_complex_type_arguments (77f526c) with main (7c3dae3)¹}

Summary

✅ 38 untouched
⏩ 7 skipped²

Footnotes

1. No successful run was found on main (4df8063) during the generation of this report, so 7c3dae3 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 7 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[leaysgur]

Talked with @Dunqing , I will retry this. roughly:

     let is_first_argument_complex = ts_type_argument_list.first().is_some_and(|first_argument| {
+        match first_argument {
+            TSType::TSTypeReference(r) => {
+                if r.type_arguments.as_ref().is_some_and(|type_args| type_args.params.len() > 1) {
+                    return true;
+                }
+
+                return matches!(
+                    r.type_arguments.as_ref().unwrap().params.first().unwrap(),
+                    TSType::TSUnionType(_)
+                | TSType::TSIntersectionType(_)
+                | TSType::TSTypeLiteral(_)
+                // TODO: This is not part of Prettier's logic, but it makes sense to consider mapped types as
+                // complex because it is the same as type literals in terms of structure.
+                // NOTE: Once the `will_break` logic is added, this will have to be revisited.
+                | TSType::TSMappedType(_)
+                );
+            }
+            _ => {}
+        }
+
         matches!(
             first_argument,
             TSType::TSUnionType(_)

Need refactoring though.

NOTE to myself: inspect(f) (and intern(f) internally) consumes comment!

[leaysgur]

We discussed concerns that comments might be discarded when attempting to print again, since the results of memoized.inspect(f) are being discarded.

However, even after modifying the code in the example, we couldn't confirm this behavior last night.

@Dunqing After investigating, I understood the reason.

oxc/crates/oxc_formatter/src/utils/assignment_like.rs

Lines 915 to 917 in e8444bf

	if f.comments().has_comment_in_span(call_expressions[0].span) {
	return false;
	}

This check runs first, so is_complex_type_arguments() was not called anyway.

But in any case, I think it's better not to use memoized.inspect(f) itself very often, so I'll redo the PR. 👉🏻 #17362