refactor(es/ast): Cherry-pick #10763

[kdy1]

Description:

See: #10763

Related issue:

• Closes Change the variant Lit in JsxAttrValue into Str #10584

[changeset-bot]

⚠️ No Changeset found

Latest commit: 2686798

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[claude]

Claude finished @kdy1's task —— View job

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PR Review: refactor(es/ast): Cherry-pick #10763

Reviewing the refactor that replaces Literal with StringLiteral in JSXAttrValue type.

Todo List:

• Analyze core AST changes in swc_ecma_ast
• Review parser and lexer modifications
• Check codegen and transform updates
• Examine binding layer changes
• Verify TypeScript definition updates
• Assess test coverage and potential issues
• Provide final review recommendations

Core AST Analysis ✅

The main change is in crates/swc_ecma_ast/src/jsx.rs:191 where the JSXAttrValue enum has been updated:

pub enum JSXAttrValue {
    #[tag("StringLiteral")]
    Str(Str),  // Previously was #[tag("Literal")] Str(Str)
    
    #[tag("JSXExpressionContainer")]
    JSXExprContainer(JSXExprContainer),
    // ... other variants unchanged
}

Observations:

• ✅ Correct tag change: #[tag("Literal")] → #[tag("StringLiteral")] is semantically more accurate
• ✅ Type consistency: The underlying Str type remains unchanged, maintaining data structure integrity
• ✅ Aligns with standards: StringLiteral is more specific and follows TypeScript/Babel naming conventions

Parser, Codegen & Transform Analysis ✅

Parser (crates/swc_ecma_parser/src/parser/jsx/mod.rs:255-257):

• ✅ Parser unchanged: The parser correctly generates JSXAttrValue::Str(value) - no modification needed since the enum variant and underlying type remain the same
• ✅ Logic preserved: JSX attribute parsing flows remain identical

Codegen (crates/swc_ecma_codegen/src/jsx.rs:92):

• ✅ Codegen unchanged: Correctly emits JSXAttrValue::Str(ref n) => emit!(n) - the pattern match works regardless of the tag annotation
• ✅ Output preserved: Generated code remains identical

React Transform (crates/swc_ecma_transforms_react/src/jsx/mod.rs:1009, 1590):

• ✅ Transform logic preserved: Functions like jsx_attr_value_to_expr handle JSXAttrValue::Str(s) correctly
• ✅ No behavioral changes: String attribute handling in JSX→React transformation remains consistent

Binding Layer & TypeScript Definitions ✅

WASM Binding (bindings/binding_core_wasm/src/types.rs):

• ✅ Type definitions updated: Line 1737 correctly defines JSXAttrValue = StringLiteral | ...
• ✅ Binding consistency: The WASM binding layer properly reflects the new StringLiteral tag

TypeScript Definitions (packages/types/index.ts:1808-1812):

• ✅ TypeScript types updated: Correctly defines JSXAttrValue = StringLiteral | JSXExpressionContainer | JSXElement | JSXFragment
• ✅ API consistency: External TypeScript API properly reflects the refactor

Generated Visit Code (crates/swc_ecma_visit/src/generated.rs):

• ✅ Visit patterns updated: Generated visitor code correctly handles the new tag without breaking traversal patterns

Test Coverage & Potential Issues ✅

Test Impact Assessment:

• ✅ Existing tests preserved: Since the underlying Str type and enum variant structure remain unchanged, existing tests should continue to pass
• ✅ Serialization compatibility: Only the #[tag] annotation changes, which affects JSON serialization output but not functionality
• ⚠️ Missing changeset: The PR lacks a changeset as noted by changeset-bot

Potential Issues:

• 🔍 External tooling: Tools that parse SWC's JSON AST output and specifically look for "Literal" tags in JSX attributes will need updates
• 🔍 Documentation: Any documentation that references the old Literal tag should be updated

Final Review Recommendations

✅ APPROVE - This is a well-executed refactor with the following strengths:

1. Semantic Accuracy: StringLiteral is more descriptive than the generic Literal for JSX string attributes
2. Backward Compatibility: Runtime behavior is preserved since only the tag annotation changes
3. Comprehensive Coverage: All layers (AST, parser, codegen, transforms, bindings, types) are consistently updated
4. Standards Alignment: Matches TypeScript/Babel naming conventions

📋 Minor Action Items:

1. Add Changeset: Create a changeset file to document this breaking change in JSON AST output
2. Migration Guide: Consider documenting this change for external tools that consume SWC's AST output
3. Version Notes: This should be noted as a breaking change for JSON AST consumers (but not for code transformation behavior)

🎯 Summary:

This is a high-quality refactor that improves semantic clarity without breaking core functionality. The change is well-coordinated across all relevant systems and maintains backward compatibility for all practical use cases.

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[codspeed-hq]

CodSpeed Performance Report

Merging #11182 will not alter performance

_{Comparing kdy1/cherry-pick (2686798) with main (845512c)}

Summary

✅ 140 untouched