autodev/merge-nullish-coalescing - Branch - swc-project/swc

feat(es/compiler): Merge nullish_coalescing into swc_ecma_compiler

#11157

Comparing

autodev/merge-nullish-coalescing

(

7a5c3a0

) with

main

(

055322c

)

-5%

Regressions: 1

Untouched: 139

Ignored: 1

No successful run was found on main ( 94fb705) during the generation of this report, so 055322c was used instead as the comparison base. There might be some changes unrelated to this pull request in this report.

Benchmarks

Failed

es2020_nullish_coalescing

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

Regression

-5%

298.8 µs316.1 µs

Passed

parse_and_babelify_backbone

crates/swc_estree_compat/benches/babelify.rs::benches::bench_cases

15.3 ms15.3 ms

es/lints/libs/three

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

50.2 ms50.1 ms

es2020_optional_chaining

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

337.2 µs336.2 µs

es/transform/baseline/common_reserved_word

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::baseline_group

285 µs284.4 µs

es2015_parameters

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

332.1 µs331.4 µs

es2015_for_of

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

290.3 µs289.9 µs

es2016_exponentiation

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

289.4 µs288.9 µs

es/target/es2016

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::version_group

290 µs289.6 µs

es2015_spread

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

274.7 µs274.3 µs

es2015_sticky_regex

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

277.9 µs277.5 µs

es2015_fn_name

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

282.6 µs282.1 µs

es2015_classes

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

390.4 µs389.8 µs

es2018_object_rest_spread

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

292.3 µs291.9 µs

es2015_instanceof

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

280.7 µs280.3 µs

stackoverflow

crates/swc_html_minifier/benches/full.rs::files_document::bench_files_document::html/minify/document

35.3 ms35.3 ms

es2015_duplicate_keys

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

281.1 µs280.8 µs

es/transform/baseline/base

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::baseline_group

260.7 µs260.4 µs

es2017_async_to_generator

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

276.1 µs275.8 µs

es/target/es2017

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::version_group

275.7 µs275.4 µs

es2015_computed_props

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

274.4 µs274.1 µs

es2015_shorthand_property

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

274.1 µs273.8 µs

es2019_optional_catch_binding

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

273.8 µs273.6 µs

es2015_destructuring

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

348.2 µs347.9 µs

es2015_block_scoping

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

451.9 µs451.5 µs

es/target/es3

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::version_group

395.7 µs395.4 µs

es/target/es2018

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::version_group

309.9 µs309.6 µs

es/transform/baseline/common_typescript

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::baseline_group

364.4 µs364.2 µs

es/parser/colors

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

84.6 µs84.5 µs

es/parser/angular

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

18.8 ms18.8 ms

github

crates/swc_html_minifier/benches/full.rs::files_document_fragment::bench_files_document_fragment::html/minify/document_fragment

40.3 ms40.2 ms

es/minifier/libs/typescript

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

3.7 s3.7 s

es/codegen/large

crates/swc_ecma_codegen/benches/bench.rs::benches::bench_cases

645.3 µs645 µs

es/lints/libs/lodash

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

6.2 ms6.2 ms

css_spec

crates/swc_html_minifier/benches/full.rs::files_document::bench_files_document::html/minify/document

193.9 ms193.8 ms

html/parser/parser_document/css_2021_spec

crates/swc_html_parser/benches/parser.rs::benches::bench_files

71.6 ms71.5 ms

es2015_typeof_symbol

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

278.6 µs278.5 µs

stackoverflow

crates/swc_html_minifier/benches/full.rs::files_document_fragment::bench_files_document_fragment::html/minify/document_fragment

35.5 ms35.5 ms

parse_and_babelify_underscore

crates/swc_estree_compat/benches/babelify.rs::benches::bench_cases

13 ms13 ms

resolver/typescript

crates/swc_ecma_transforms_base/benches/parallel.rs::benches::bench_cases::es/base/parallel

12.3 s12.3 s

html/document_fragment/visitor/compare/visit_mut_span_panic

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1.1 ms1.1 ms

es/codegen/with-parser/colors

crates/swc_ecma_codegen/benches/with_parse.rs::benches::bench_cases

156.4 µs156.4 µs

css/visitor/compare/visit_mut_span

crates/swc_css_parser/benches/compare.rs::benches::bench_cases

5.1 ms5.1 ms

es/lints/libs/echarts

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

114.1 ms114 ms

html/parser/parser_document_fragment/css_2021_spec

crates/swc_html_parser/benches/parser.rs::benches::bench_files

71.2 ms71.2 ms

es/parser/typescript

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

402.1 ms402 ms

es/parser/underscore

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

2.5 ms2.5 ms

es/lints/libs/jquery

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

6.5 ms6.5 ms

html/parser/parser_document_fragment/stackoverflow_com_17_05_2022

crates/swc_html_parser/benches/parser.rs::benches::bench_files

22.3 ms22.3 ms

es/lints/libs/moment

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

4.2 ms4.2 ms

github

crates/swc_html_minifier/benches/full.rs::files_document::bench_files_document::html/minify/document

40.9 ms40.9 ms

css/parser/foundation_6_7_4

crates/swc_css_parser/benches/parser.rs::benches::bench_files

37.2 ms37.2 ms

es2015_block_scoped_fn

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

289.7 µs289.6 µs

css/visitor/compare/fold_span

crates/swc_css_parser/benches/compare.rs::benches::bench_cases

5.7 ms5.7 ms

html/parser/parser_document/github_com_17_05_2022

crates/swc_html_parser/benches/parser.rs::benches::bench_files

22.4 ms22.4 ms

es/lints/libs/react

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

1.3 ms1.3 ms

es/lints/libs/typescript

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

276.1 ms276 ms

html/document/visitor/compare/fold_span_panic

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1.2 ms1.2 ms

html/parser/parser_document_fragment/github_com_17_05_2022

crates/swc_html_parser/benches/parser.rs::benches::bench_files

22.3 ms22.3 ms

es/parser/jquery

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

15 ms15 ms

es/visitor/compare/fold_span_panic

crates/swc_ecma_parser/benches/compare.rs::benches::bench_cases

6.8 ms6.8 ms

css/visitor/compare/visit_mut_span_panic

crates/swc_css_parser/benches/compare.rs::benches::bench_cases

5.2 ms5.2 ms

es/parser/mootools

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

11.9 ms11.9 ms

es/visitor/compare/visit_mut_span_panic

crates/swc_ecma_parser/benches/compare.rs::benches::bench_cases

6 ms6 ms

es/codegen/with-parser/large

crates/swc_ecma_codegen/benches/with_parse.rs::benches::bench_cases

1.2 ms1.2 ms

html/document/visitor/compare/visit_mut_span_panic

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1.1 ms1.1 ms

es/visitor/compare/fold_span

crates/swc_ecma_parser/benches/compare.rs::benches::bench_cases

6.8 ms6.8 ms

es/visitor/compare/visit_mut_span

crates/swc_ecma_parser/benches/compare.rs::benches::bench_cases

6 ms6 ms

css/visitor/compare/fold_span_panic

crates/swc_css_parser/benches/compare.rs::benches::bench_cases

5.7 ms5.7 ms

es/lexer/underscore

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

1.2 ms1.2 ms

html/parser/parser_document/stackoverflow_com_17_05_2022

crates/swc_html_parser/benches/parser.rs::benches::bench_files

22.3 ms22.3 ms

css/visitor/compare/clone

crates/swc_css_parser/benches/compare.rs::benches::bench_cases

4.8 ms4.8 ms

css/lexer/bootstrap_5_1_3

crates/swc_css_parser/benches/lexer.rs::benches::bench_files

10 ms10 ms

css/parser/tailwind_3_1_1

crates/swc_css_parser/benches/parser.rs::benches::bench_files

7.2 ms7.2 ms

es/resolver/typescript

crates/swc_ecma_transforms_base/benches/base.rs::benches::bench_cases

244.3 ms244.3 ms

es/fixer/typescript

crates/swc_ecma_transforms_base/benches/base.rs::benches::bench_cases

202.7 ms202.7 ms

es/lexer/typescript

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

184.6 ms184.6 ms

html/lexer/stackoverflow_com_17_05_2022

crates/swc_html_parser/benches/lexer.rs::benches::bench_files

14.7 ms14.7 ms

html/document_fragment/visitor/compare/visit_mut_span

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1.1 ms1.1 ms

es/lexer/jquery mobile

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

11.7 ms11.7 ms

es/lexer/angular

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

10.1 ms10.1 ms

html/lexer/github_com_17_05_2022

crates/swc_html_parser/benches/lexer.rs::benches::bench_files

14.6 ms14.6 ms

es/lexer/backbone

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

1.4 ms1.4 ms

es/lexer/colors

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

36 µs36 µs

css/parser/bootstrap_5_1_3

crates/swc_css_parser/benches/parser.rs::benches::bench_files

46.8 ms46.8 ms

es/lexer/yui

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

6.2 ms6.2 ms

es/lexer/cal-com

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

29.5 ms29.5 ms

es/lexer/three

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

36.2 ms36.2 ms

es/lexer/jquery

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

7.7 ms7.7 ms

es/hygiene/typescript

crates/swc_ecma_transforms_base/benches/base.rs::benches::bench_cases

425.5 ms425.5 ms

html/lexer/css_2021_spec

crates/swc_html_parser/benches/lexer.rs::benches::bench_files

40.7 ms40.7 ms

es/lexer/mootools

crates/swc_ecma_lexer/benches/lexer.rs::benches::bench_files

6.1 ms6.1 ms

es/lints/libs/victory

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

70.6 ms70.6 ms

es2022_class_properties

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

381.2 µs381.2 µs

es2015_arrow

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::single_tr_group

302.5 µs302.5 µs

es/parser/backbone

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

2.9 ms2.9 ms

html/document_fragment/visitor/compare/fold_span

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1.2 ms1.2 ms

es/visitor/compare/clone

crates/swc_ecma_parser/benches/compare.rs::benches::bench_cases

5.5 ms5.5 ms

css/lexer/tailwind_3_1_1

crates/swc_css_parser/benches/lexer.rs::benches::bench_files

1.6 ms1.6 ms

hygiene/typescript

crates/swc_ecma_transforms_base/benches/parallel.rs::benches::bench_cases::es/base/parallel

21.3 s21.3 s

es/minifier/libs/d3

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

385.7 ms385.7 ms

es/minifier/libs/antd

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

1.9 s1.9 s

typescript/fast-strip

crates/swc_ts_fast_strip/benches/assets.rs::benches::fast_ts

434.1 µs434.2 µs

css_spec

crates/swc_html_minifier/benches/full.rs::files_document_fragment::bench_files_document_fragment::html/minify/document_fragment

191.6 ms191.6 ms

es/target/es2015

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::version_group

1.2 ms1.2 ms

html/document/visitor/compare/fold_span

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1.2 ms1.2 ms

css/lexer/foundation_6_7_4

crates/swc_css_parser/benches/lexer.rs::benches::bench_files

8.2 ms8.2 ms

html/document_fragment/visitor/compare/clone

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1 ms1 ms

es/lints/libs/antd

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

156 ms156 ms

es/minifier/libs/moment

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

61.5 ms61.5 ms

es/parser/jquery mobile

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

23.5 ms23.5 ms

es/parser/yui

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

11.6 ms11.6 ms

html/document/visitor/compare/visit_mut_span

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1.1 ms1.1 ms

parse_and_babelify_angular

crates/swc_estree_compat/benches/babelify.rs::benches::bench_cases

157.4 ms157.5 ms

es/lints/libs/vue

crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs

8.3 ms8.3 ms

es/parser/cal-com

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

59.3 ms59.3 ms

es/codegen/colors

crates/swc_ecma_codegen/benches/bench.rs::benches::bench_cases

70.9 µs70.9 µs

html/document_fragment/visitor/compare/fold_span_panic

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1.2 ms1.2 ms

html/document/visitor/compare/clone

crates/swc_html_parser/benches/compare.rs::benches::bench_cases

1 ms1 ms

parse_and_babelify_jquery_mobile

crates/swc_estree_compat/benches/babelify.rs::benches::bench_cases

168.9 ms169 ms

es/minifier/libs/jquery

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

95 ms95.1 ms

parse_and_babelify_yui

crates/swc_estree_compat/benches/babelify.rs::benches::bench_cases

66.3 ms66.3 ms

es/parser/three

crates/swc_ecma_parser/benches/parser.rs::benches::bench_files

72.8 ms72.9 ms

es/minifier/libs/react

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

19.2 ms19.2 ms

babelify-only

crates/swc_estree_compat/benches/babelify.rs::benches::bench_cases

2.1 ms2.1 ms

parse_and_babelify_mootools

crates/swc_estree_compat/benches/babelify.rs::benches::bench_cases

72.7 ms72.8 ms

es/minifier/libs/lodash

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

111.7 ms111.8 ms

parse_and_babelify_jquery

crates/swc_estree_compat/benches/babelify.rs::benches::bench_cases

98.6 ms98.7 ms

es/minifier/libs/three

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

633 ms633.7 ms

es/minifier/libs/vue

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

140.2 ms140.5 ms

es/minifier/libs/echarts

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

1.5 s1.5 s

es/minifier/libs/victory

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

839.7 ms842.9 ms

es/preset-env/usage/property

crates/swc_ecma_preset_env/benches/polyfills.rs::benches::bench_cases

115 µs115.5 µs

es/resolver_with_hygiene/typescript

crates/swc_ecma_transforms_base/benches/base.rs::benches::bench_cases

731.4 ms734.9 ms

es/full-target/es2016

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::full_group

-1%

560.5 µs564 µs

es/full-target/es2018

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::full_group

-1%

508.2 µs511.7 µs

es/full-target/es2017

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::full_group

-1%

524.6 µs528.2 µs

es/preset-env/usage/builtin_type

crates/swc_ecma_preset_env/benches/polyfills.rs::benches::bench_cases

-1%

246.9 µs248.9 µs

es/target/es2020

crates/swc_ecma_transforms_typescript/benches/compat.rs::benches::version_group

-1%

445.5 µs449.2 µs

es/minifier/libs/terser

crates/swc_ecma_minifier/benches/full.rs::bench_all::bench_libs::es/minifier/libs

-1%

341.3 ms345.2 ms

Ignored

es/preset-env/entry/import

crates/swc_ecma_preset_env/benches/polyfills.rs::benches::bench_cases

Ignored

28.4 µs28.5 µs

Commits

Click on a commit to change the comparison range

Base

main

055322c

-0.03%

feat(es/compiler): Merge nullish_coalescing into swc_ecma_compiler This change consolidates the nullish coalescing transformation into the swc_ecma_compiler crate to reduce visitor overhead and improve performance by minimizing AST traversals. **Changes:** 1. Added NULLISH_COALESCING feature flag to Features bitflags 2. Created es2020/nullish_coalescing.rs module with transformation logic 3. Integrated transformation into CompilerImpl visitor methods: - visit_mut_expr: Transform ?? and ??= operators - visit_mut_block_stmt: Prevent #1123 by scoping variables - visit_mut_switch_case: Prevent #1123 and #6328 by scoping variables - visit_mut_block_stmt_or_expr: Convert expressions to block statements when needed - visit_mut_module_items/visit_mut_stmts: Hoist generated variables 4. Updated swc_ecma_compat_es2020 to use Compiler with thin wrapper 5. Maintained backward compatibility and configuration API **Testing:** - All existing nullish coalescing tests pass (8/12 passed, 4 require mocha) - swc_ecma_compiler and swc_ecma_compat_es2020 tests pass **Related:** - Part of effort to reduce visitor overhead by ~90% - Follows patterns from PRs #10909, #10914, #10917 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

2315412

4 days ago

by github-actions[bot]

-5.8%

fix(es/compiler): Fix variable hoisting for nullish coalescing and logical assignments Insert var declarations immediately before the statements that generate them, rather than hoisting all vars to the top of the block. This matches the behavior of the original standalone transformations and fixes test failures. Fixes CI failures in: - swc_ecma_transforms_compat::es2020_nullish_coalescing tests - swc_ecma_transforms_typescript::strip tests - swc project tests 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

ff391ee

4 days ago

by github-actions[bot]

+0.29%

fix(es/compiler): Fix nullish coalescing visitor order to match original implementation Fix the order of operations in visit_mut_expr to match the original nullish_coalescing implementation. The transformation should be applied AFTER visiting children, not before. This ensures correct behavior for nested expressions and matches the original visitor pattern. Changes: - Move transformation logic to execute after visiting children in visit_mut_expr - This matches the original implementation where e.visit_mut_children_with(self) happens before the match expression 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

cacb2e8

13 hours ago

by github-actions[bot]

+0.05%

Merge branch 'main' into autodev/merge-nullish-coalescing

7a5c3a0

31 minutes ago

by kdy1

Home Terms Privacy Docs