feat(parse/astro): add astro parser / formatter #6701

emilienbidet · 2025-07-04T11:26:58Z

Summary

This PR adds initial Astro parser and formatter support to Biome, providing a foundation for handling .astro files. The implementation was generated by Claude Code and inspired by the prettier-plugin-astro repository to help quick-start Astro support in Biome.

Motivation

I really love using Biome for its speed and comprehensive tooling, and I would like to use it with Astro projects. This contribution aims to bridge that gap by providing basic Astro file support.

What's been done

Added Astro syntax parsing capabilities
Implemented basic Astro file formatting
Created foundational structure for Astro language support
Based implementation on patterns from prettier-plugin-astro for compatibility

Test plan

Test Astro file parsing with various syntax patterns
Test Astro file formatting maintains correct structure
Verify integration with existing Biome toolchain
Run existing test suite to ensure no regressions

Notes

This is an initial implementation to get Astro support started. Further refinements and feature additions can be made in follow-up PRs based on community feedback and usage patterns.

🤖 Generated with Claude Code

changeset-bot · 2025-07-04T11:27:02Z

⚠️ No Changeset found

Latest commit: 19992d1

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

dyc3

Nothing immediately sticks out to me as particularly problematic, from a code perspective. This PR does adequately follow the project's patterns and conventions.

However, I'm not sure this is the direction we want to go architecturally. This PR effectively seeks to duplicate the effort of the HTML parser and formatter. We do want to be able to reuse that logic, because its a lot of work to maintain multiple implementations of effectively the same thing.

ematipico · 2025-07-04T12:07:51Z

@dyc3 is right, and in fact we want to extend the HTML parser, and handle vue/svelte/astro files.

In fact, in this PR we already implemented the parsing of Astro frontmatter in Astro files #6689

That's the direction we're taking

Add Astro-specific syntax nodes to HTML grammar: - HtmlAstroExpression for {expr} syntax - HtmlAstroShorthandAttribute for {name} syntax - HtmlAstroSpreadAttribute for {...props} syntax - HtmlAstroExpressionAttribute for name={expr} syntax - HtmlAstroTemplateLiteralAttribute for name={`template`} syntax - HtmlAstroFragment for Astro fragment syntax This extends the HTML parser to handle Astro expressions and attributes as requested by maintainers, avoiding code duplication by reusing the HTML parser infrastructure. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>

Regenerate HTML syntax files with new Astro syntax nodes: - Add Astro syntax kinds to HtmlSyntaxKind enum - Add missing HTML_JS_CONTENT and HTML_TEMPLATE_LITERAL_CONTENT kinds - Update T\! macro to support new tokens: { } ` ... - Generate AST node structs for all Astro syntax nodes These generated files enable the parser to create proper AST nodes for Astro expressions and attributes. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>

Add support for Astro-specific tokens in HTML lexer: - Support { } tokens in Regular and OutsideTag contexts - Support backtick (`) tokens for template literals - Add consume_dot_or_dot_dot_dot() for spread operator (...) - Tokens are properly recognized in both tag and content contexts This enables the lexer to tokenize Astro expressions like {name}, {...props}, and {`template`} while maintaining HTML compatibility. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>

Add comprehensive parsing support for Astro syntax: - parse_astro_expression() for {expr} in content - parse_astro_shorthand_attribute() for {name} attributes - parse_astro_spread_attribute() for {...props} attributes - parse_astro_expression_attribute() for name={expr} - parse_astro_template_literal_attribute() for name={`template`} - Component vs element detection logic (PascalCase detection) Integrate parsing functions into ElementList and AttributeList: - ElementList handles Astro expressions in content - AttributeList handles all Astro attribute types - Enhanced attribute_initializer to support Astro expressions This provides complete parsing of Astro's unique syntax while extending the existing HTML parser infrastructure. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>

Generate and update HTML formatter for Astro syntax nodes: - Run codegen to generate formatter files for all Astro nodes - Update any/attribute.rs and any/element.rs to handle Astro cases - Update attribute_list.rs to format Astro attributes - All Astro formatters use format_verbatim_node() for now This ensures that Astro syntax can be formatted without compilation errors, providing basic formatting support while maintaining the structure of Astro expressions and attributes. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>

Add lexer tests covering all Astro syntax features: - astro_expression_simple: Basic {name} expressions - astro_spread_attribute: Spread syntax {...props} - astro_expression_attribute: Attribute expressions name={value} - astro_template_literal: Template literals with backticks - astro_frontmatter_fence: Frontmatter --- blocks - astro_component_tag: PascalCase component recognition - astro_complex_expression: Complex JavaScript expressions - astro_mixed_attributes: Mixed HTML and Astro attributes Tests validate proper tokenization in various HTML contexts and ensure lexer correctly identifies Astro-specific tokens while maintaining HTML compatibility. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>

codspeed-hq · 2025-07-06T16:35:08Z

CodSpeed Performance Report

Merging #6701 will not alter performance

_{Comparing emilienbidet:main (19992d1) with main (52e36ae)}

Summary

✅ 114 untouched benchmarks

Regenerate the HTML formatter generated.rs file to include complete AsFormat trait implementations for all Astro syntax nodes. This fixes the CI build errors where the formatter couldn't find format() methods for Astro nodes. The codegen command now properly generates all necessary trait implementations. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>

…rser Remove standalone Astro parser infrastructure and fully integrate Astro support into the HTML parser as requested by maintainers: - Remove biome_astro_parser, biome_astro_syntax, biome_astro_factory, biome_astro_formatter - Update service handlers to use HTML parser for Astro files - Update factory files after grammar regeneration - Remove Astro configuration from separate module This completes the transition from duplicate standalone parsers to extending the HTML parser infrastructure, addressing maintainer feedback to avoid code duplication. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>

dyc3 · 2025-07-07T19:14:13Z

crates/biome_js_formatter/tests/specs/prettier/.DS_Store

Not sure how this got in here, but this file needs to be removed.

dyc3 · 2025-07-07T19:16:14Z

xtask/codegen/astro.ungram

dyc3 · 2025-07-07T19:17:46Z

xtask/codegen/html.ungram

+// ==================================
+// Astro-specific syntax nodes
+// ==================================
+
+// Astro expressions: {expression}
+HtmlAstroExpression =
+	l_curly: '{'


For these, I think it would be better to prefix them with just Astro instead of HtmlAstro. This would be more consistent with how js and ts nodes are named.

dyc3 · 2025-07-07T19:21:13Z

crates/biome_service/src/file_handlers/astro.rs

+                formatter: Some(html::formatter_enabled),
+                search: Some(html::search_enabled),
+                assist: Some(html::assist_enabled),
+                linter: Some(html::linter_enabled),


Let's refrain from making public facing changes for now. We haven't made enough progress to do that yet -- if we were to merge this we would regress in functionality.

dyc3 · 2025-07-07T19:22:31Z

crates/biome_html_parser/src/syntax/mod.rs

@@ -81,10 +90,11 @@ fn parse_element(p: &mut HtmlParser) -> ParsedSyntax {

    p.bump(T![<]);
    let opening_tag_name = p.cur_text().to_string();
-    let should_be_self_closing = VOID_ELEMENTS
+    let is_component = is_astro_component(&opening_tag_name);


I think it would be better to have astro specific logic gated behind a parser option.

dyc3 · 2025-07-07T19:24:50Z

crates/biome_html_parser/src/syntax/astro.rs

There's a lot of new logic here that is not covered by snapshot tests.

feat(parse/astro): add astro parser / formatter

e42b0b9

github-actions bot added A-Project Area: project A-Parser Area: parser A-Formatter Area: formatter A-Tooling Area: internal tools labels Jul 4, 2025

dyc3 reviewed Jul 4, 2025

View reviewed changes

emilienbidet and others added 6 commits July 6, 2025 18:14

github-actions bot added the L-HTML Language: HTML label Jul 6, 2025

emilienbidet requested a review from dyc3 July 6, 2025 16:29

emilienbidet and others added 2 commits July 6, 2025 18:38

emilienbidet force-pushed the main branch from c228a47 to 19992d1 Compare July 6, 2025 17:57

github-actions bot added L-JavaScript Language: JavaScript and super languages L-CSS Language: CSS L-JSON Language: JSON and super languages L-Grit Language: GritQL labels Jul 6, 2025

dyc3 requested changes Jul 7, 2025

View reviewed changes

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Uh oh!

feat(parse/astro): add astro parser / formatter #6701

feat(parse/astro): add astro parser / formatter #6701

emilienbidet commented Jul 4, 2025 •

edited

Loading

Uh oh!

changeset-bot bot commented Jul 4, 2025 •

edited

Loading

Uh oh!

dyc3 left a comment

Uh oh!

ematipico commented Jul 4, 2025

Uh oh!

codspeed-hq bot commented Jul 6, 2025 •

edited

Loading

Uh oh!

dyc3 Jul 7, 2025

Uh oh!

dyc3 Jul 7, 2025

Uh oh!

dyc3 Jul 7, 2025

Uh oh!

dyc3 Jul 7, 2025

Uh oh!

dyc3 Jul 7, 2025

Uh oh!

dyc3 Jul 7, 2025

Uh oh!

Uh oh!

Uh oh!

feat(parse/astro): add astro parser / formatter #6701

Are you sure you want to change the base?

feat(parse/astro): add astro parser / formatter #6701

Conversation

emilienbidet commented Jul 4, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Motivation

What's been done

Test plan

Notes

Uh oh!

changeset-bot bot commented Jul 4, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

⚠️ No Changeset found

Uh oh!

dyc3 left a comment

Choose a reason for hiding this comment

Uh oh!

ematipico commented Jul 4, 2025

Uh oh!

codspeed-hq bot commented Jul 6, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

CodSpeed Performance Report

Merging #6701 will not alter performance

Summary

Uh oh!

dyc3 Jul 7, 2025

Choose a reason for hiding this comment

Uh oh!

dyc3 Jul 7, 2025

Choose a reason for hiding this comment

Uh oh!

dyc3 Jul 7, 2025

Choose a reason for hiding this comment

Uh oh!

dyc3 Jul 7, 2025

Choose a reason for hiding this comment

Uh oh!

dyc3 Jul 7, 2025

Choose a reason for hiding this comment

Uh oh!

dyc3 Jul 7, 2025

Choose a reason for hiding this comment

Uh oh!

Uh oh!

emilienbidet commented Jul 4, 2025 •

edited

Loading

changeset-bot bot commented Jul 4, 2025 •

edited

Loading

codspeed-hq bot commented Jul 6, 2025 •

edited

Loading