fix(transformer/typescript): panic occurs when declare property and definite property that has initializer

[Dunqing]

Remove two incorrect assertions, which cause panic in the #13766.

The declare property with an initializer is allowed in TypeScript

class DeclareExample {
  declare readonly bar = "test";
  declare readonly foo = 1;
}

The ! (definite) with an initializer isn't allowed in TypeScript, but this is a recoverable error, so the AST can have such.

class DefiniteExample {
   readonly bar! = "test";
   readonly foo! = 1;
}

[Dunqing]

• fix(transformer/class-properties): don't transform properties that have declare modifier #13766
• fix(transformer/typescript): panic occurs when declare property and definite property that has initializer #13785 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR fixes a panic in the TypeScript transformer when handling class properties with both declare and definite assignment assertion modifiers that have initializers.

• Removes assertion checks that were causing panics for declare and definite properties with initializers
• Adds test coverage for the fixed behavior with both declare and definite properties

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
crates/oxc_transformer/src/typescript/annotations.rs	Removes panic-causing assertions for declare and definite properties with initializers
tasks/transform_conformance/tests/babel-plugin-transform-typescript/test/fixtures/declare-and-definite-with-initializer/input.ts	Test input showing declare and definite properties with initializers
tasks/transform_conformance/tests/babel-plugin-transform-typescript/test/fixtures/declare-and-definite-with-initializer/output.js	Expected output after transformation
tasks/transform_conformance/snapshots/oxc.snap.md	Updates test count to reflect new passing test

Comments suppressed due to low confidence (1)

crates/oxc_transformer/src/typescript/annotations.rs:352

• The function removes TypeScript-specific property modifiers but lacks documentation explaining why declare and definite properties with initializers are now allowed, given that the removed assertions suggested this was previously considered invalid.

    fn enter_property_definition(
        &mut self,
        def: &mut PropertyDefinition<'a>,
        _ctx: &mut TraverseCtx<'a>,
    ) {
        def.accessibility = None;
        def.definite = false;
        def.r#override = false;
        def.optional = false;
        def.readonly = false;
        def.type_annotation = None;
    }

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13785 will not alter performance

_{Comparing 09-15-fix_transformer_typescript_panics_when_declare_property_and_definite_property_with_initializer (7d0b8a1) with main (26af302)¹}

Summary

✅ 37 untouched

Footnotes

1. No successful run was found on main (7d0b8a1) during the generation of this report, so 26af302 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[overlookmotel]

Merge activity

• Sep 16, 12:56 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Sep 16, 12:56 PM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Sep 16, 1:02 PM UTC: Merged by the Graphite merge queue.