perf(formatter): reuse previous indent stack in FitsMeasurer

[Dunqing]

As said in

oxc/crates/oxc_formatter/src/formatter/printer/mod.rs

Lines 703 to 708 in 6084899

	// Re-used queue to measure if a group fits. Optimisation to avoid re-allocating a new
	// vec everytime a group gets measured
	fits_stack: Vec<StackFrame>,
	fits_indent_stack: Vec<Indention>,
	fits_stack_tem_indent: Vec<Indention>,
	fits_queue: Vec<&'a [FormatElement<'a>]>,

These four stacks should be reused in each FitsMeasurer run to avoid reallocation, but fits_indent_stack and `fits_stack_tem_indent are lacking.

[Dunqing]

• perf(formatter): use ArenaVec and ArenaBox #15420
• perf(formatter): reuse previous indent stack in FitsMeasurer #15416 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #15416 will not alter performance

_{Comparing 11-07-perf_formatter_reuse_previous_indent_stack_in_fitsmeasurer (86f714d) with main (2820a39)¹}

Summary

✅ 33 untouched
⏩ 4 skipped²

Footnotes

1. No successful run was found on main (2ad77fb) during the generation of this report, so 2820a39 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 4 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. ↩

[Copilot]

Pull Request Overview

This pull request extends the resource cleanup mechanism in the formatter's FitsMeasurer to properly handle indent stack resources. The changes ensure that indent stacks are recycled and reused across fits measurements, preventing unnecessary allocations.

• Adds a finish method to FitsIndentStack that extracts both the indent stack and history stack vectors
• Updates the FitsMeasurer::finish method to properly clear and return both indent stacks to the printer state for reuse

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
crates/oxc_formatter/src/formatter/printer/call_stack.rs	Implements finish method for FitsIndentStack to extract and return both indent vectors
crates/oxc_formatter/src/formatter/printer/mod.rs	Extends FitsMeasurer::finish to clear and recycle indent stacks back to printer state

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[leaysgur]

Please merge after addressing Copilot suggestion( which seems valid?). 🙆🏻‍♂️

[Dunqing]

Merge activity

• Nov 7, 10:17 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 7, 10:19 AM UTC: Dunqing added this pull request to the Graphite merge queue.
• Nov 7, 10:27 AM UTC: Merged by the Graphite merge queue.