feat(estree): add IS_COMPACT const to Formatter trait

[overlookmotel]

Add IS_COMPACT const to Formatter and Serializer traits. In conjunction with #19773, callers can manually construct JSON themselves in the correct format for the serializer (compact or pretty-printed).

This is used in #19744 to net a +9% perf gain in ESTree token serialization.

[overlookmotel]

• perf(estree/tokens): use strings from AST for identifier tokens #19744 : 2 dependent PRs (#19735 , #19796 )
• refactor(estree/tokens): add TokenType type #19789
• feat(estree): add IS_COMPACT const to Formatter trait #19787 👈 (View in Graphite)
• feat(estree): expose buffer and formatter of serializers #19773
• perf(estree): use CodeBuffer::print_strs_array to reduce bounds checks #19766
• feat(data_structures): add CodeBuffer::print_strs_array #19760
• perf(estree): use CodeBuffer::print_indent #19727
• perf(estree/tokens): serialize tokens while visiting AST #19726
• perf(estree/tokens): serialize with ESTree not serde #19725
• feat(estree): oxc_estree crate export config and formatter types #19724
• refactor(estree/tokens): convert tokens spans before AST spans #19723
• refactor(estree/tokens): simplify code #19722
• perf(estree/tokens): do not branch on presence of override twice #19721
• refactor(estree/tokens): move logic for excluding legacy identifiers into visitor #19720
• perf(estree/tokens): replace hash map with Vec #19718
• perf(estree/tokens): replace multiple hash sets into a single hash map #19716
• refactor(estree/tokens): replace stored token when re-lexing #19698
• perf(parser): remove branches from finish_next_inner #19695
• perf(parser): remove const generic param from finish_next_inner #19684
• feat(parser): add LexerConfig::TOKENS_METHOD_IS_STATIC const #19683
• docs(parser): improve doc comments for ParserConfig and LexerConfig #19682
• refactor(estree/tokens): use wildcard import for AST types #19681
• test(estree): ESTree conformance check files with hashbangs #19680
• fix(estree/tokens): reverse field order of regex object in tokens #19679
• perf(estree/tokens): serialize tokens to compact JSON #19572
• ci(benchmarks): correct comment #19650
• perf(parser/tokens): pre-allocate capacity for tokens #19543
• fix(estree/tokens): generate tokens for files with BOM #19535
• refactor(estree/tokens): combine collect_token_context into to_estree_tokens_json #19534
• refactor(estree): reorder tokens code #19533
• refactor(coverage): standardize ESTree tokens testing functions #19532
• perf(linter/plugins): remove typescript from bundle #19531
• docs(linter/plugins): correct doc comments for initTokens #19530
• refactor(linter/plugins): combine functions for getting tokens #19529
• ci(benchmarks): benchmark parser with tokens and ESTree tokens conversion #19649
• perf(linter/plugins): use Oxc tokens in plugins #19498
• test(estree/tokens): do not skip tokens conformance tests for files with hashbangs #19643
• fix(estree): fix tokens for JSX #19524
• perf(parser): introduce ParserConfig #19637
• feat(parser,estree,coverage): collect tokens in parser and convert to ESTree format #19497
• feat(coverage): add estree token conformance scaffolding #19496
• fix(tasks/coverage): bring back acorn-jsx estree testing #19516 : 1 other dependent PR (#19515 )
• chore(submodules): update submodule SHAs to latest commits #19518
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 52 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing om/02-26-feat_estree_add_is_compact_const_to_formatter_trait (8b9f2ae) with om/02-26-feat_estree_expose_buffer_and_formatter_of_serializers (6f29d1c)²}

Footnotes

1. 3 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. ↩

2. No successful run was found on om/02-26-feat_estree_expose_buffer_and_formatter_of_serializers (aea71cc) during the generation of this report, so d1f4b1c was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Copilot]

Pull request overview

This PR adds an IS_COMPACT associated constant to both the Formatter and Serializer traits, enabling callers to determine at compile-time whether a serializer produces compact or pretty-printed JSON. This change supports performance optimizations in #19744 (which achieves a +9% perf gain in ESTree token serialization) by allowing callers to manually construct JSON in the correct format when working with the low-level APIs exposed in #19773.

Changes:

• Add IS_COMPACT const to Formatter trait with implementations in CompactFormatter and PrettyFormatter
• Add IS_COMPACT const to Serializer trait with a default value that delegates to the formatter

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
crates/oxc_estree/src/serialize/formatter.rs	Adds IS_COMPACT const to Formatter trait and implements it as true for CompactFormatter and false for PrettyFormatter
crates/oxc_estree/src/serialize/mod.rs	Adds IS_COMPACT const to Serializer trait with a default value that delegates to Self::Formatter::IS_COMPACT

[graphite-app]

Merge activity

• Feb 27, 12:10 AM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Feb 27, 12:17 AM UTC: Merged by the Graphite merge queue.