fix(transformer/typescript): namespaces disappeared and do not transform when a type-only namespace followed by a value module namespace

[Dunqing]

Input:

// SymbolFlags: NameSpaceModule
export namespace Foo {
	 export type T = 0;
}
// SymbolFlags: ValueModule
export namespace Foo {
	 export const Bar = 1;
}

Before output:

expot {}

After Output:

// SymbolFlags: ValueModule
export let Foo;
(function(_Foo) {
  const Bar = _Foo.Bar = 1;
})(Foo || (Foo = {}));

When both NameSpaceModule and ValueModule are present, we need to check the current
declaration flags. If the current declaration is NameSpaceModule, we can return early
because it's a type-only namespace and doesn't emit any JS code, otherwise we need to
continue transforming it.

[Dunqing]

• fix(transformer/typescript): namespaces disappeared and do not transform when a type-only namespace followed by a value module namespace #10511 👈 (View in Graphite)
• fix(transformer/typescript): variable declaration disappears when declaring type-alias/interface first and then declaring namespace #10510
• main

---

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #10511 will create unknown performance changes

_{Comparing 04-20-fix_transformer_typescript_namespaces_disappeared_and_do_not_transform_when_a_type-only_namespace_followed_by_a_value_module_namespace (33a2625) with 04-20-fix_transformer_typescript_variable_declaration_disappears_when_declaring_type-alias_interface_first_and_then_declaring_namespace (710a35c)}

Summary

🆕 36 new benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	codegen[checker.ts]	N/A	22.2 ms	N/A
🆕	codegen_sourcemap[checker.ts]	N/A	65.1 ms	N/A
🆕	formatter[antd.js]	N/A	708.5 ms	N/A
🆕	formatter[react.development.js]	N/A	8 ms	N/A
🆕	formatter[typescript.js]	N/A	1.1 s	N/A
🆕	isolated-declarations[vue-id.ts]	N/A	58.4 ms	N/A
🆕	lexer[RadixUIAdoptionSection.jsx]	N/A	21.3 µs	N/A
🆕	lexer[antd.js]	N/A	24.8 ms	N/A
🆕	lexer[cal.com.tsx]	N/A	5.9 ms	N/A
🆕	lexer[checker.ts]	N/A	14.9 ms	N/A
🆕	lexer[pdf.mjs]	N/A	3.9 ms	N/A
🆕	linter[RadixUIAdoptionSection.jsx]	N/A	2.7 ms	N/A
🆕	linter[cal.com.tsx]	N/A	1.2 s	N/A
🆕	linter[checker.ts]	N/A	3 s	N/A
🆕	mangler[antd.js]	N/A	15.9 ms	N/A
🆕	mangler[react.development.js]	N/A	293.2 µs	N/A
🆕	mangler[typescript.js]	N/A	39.4 ms	N/A
🆕	minifier[antd.js]	N/A	163.5 ms	N/A
🆕	minifier[react.development.js]	N/A	1.8 ms	N/A
🆕	minifier[typescript.js]	N/A	287.9 ms	N/A
...	...	...	...	...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

[Boshen]

Merge activity

• Apr 21, 5:19 AM EDT: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Apr 21, 5:19 AM EDT: Boshen added this pull request to the Graphite merge queue.
• Apr 21, 5:31 AM EDT: Merged by the Graphite merge queue.