fix(bundle): leave template literal text alone when renaming identifiers

packages/dtsx/src/bundle-linker.tsmodified+42-3

Changes to packages/dtsx/src/bundle-linker.ts

		⋯331 linesShow the 331 lines above this hunk@@ -332,9 +332,9 @@ function parseModule(file: string, dts: string): ModuleInfo {
332	332	}
333	333
334	334	/**
335		- * Rename identifier references in declaration text. Strings, comments,
336		- * qualified-name members (`a.b`) and property or parameter names (`{ b: T }`,
337		- * `(b: T)`) are left alone.
	335	+ * Rename identifier references in declaration text. Strings, template literal
	336	+ * text (not its `${}` placeholders), comments, qualified-name members (`a.b`)
	337	+ * and property or parameter names (`{ b: T }`, `(b: T)`) are left alone.
338	338	*/
339	339	export function renameIdentifiers(text: string, renames: Map<string, string>): string {
340	340	if (renames.size === 0) return text
		⋯1 lineShow the 1 line above this hunk@@ -342,8 +342,47 @@ export function renameIdentifiers(text: string, renames: Map<string, string>): s
342	342	let i = 0
343	343	const n = text.length
344	344	let lastSignificant = '\n'
	345	+ // One entry per template literal or placeholder the scan is in: -1 for
	346	+ // template text, otherwise the braces open inside that placeholder.
	347	+ const templates: number[] = []
345	348	while (i < n) {
346	349	const c = text[i]
	350	+ if (templates.length > 0 && templates[templates.length - 1] === -1) {
	351	+ if (c === '\\') {
	352	+ out += text.slice(i, i + 2)
	353	+ i += 2
	354	+ }
	355	+ else if (c === '`') {
	356	+ templates.pop()
	357	+ out += c
	358	+ lastSignificant = c
	359	+ i++
	360	+ }
	361	+ else if (c === '$' && text[i + 1] === '{') {
	362	+ templates.push(0)
	363	+ out += '${'
	364	+ lastSignificant = '{'
	365	+ i += 2
	366	+ }
	367	+ else {
	368	+ out += c
	369	+ i++
	370	+ }
	371	+ continue
	372	+ }
	373	+ if (c === '`') {
	374	+ templates.push(-1)
	375	+ out += c
	376	+ i++
	377	+ continue
	378	+ }
	379	+ if (templates.length > 0 && c === '{') {
	380	+ templates[templates.length - 1]++
	381	+ }
	382	+ else if (templates.length > 0 && c === '}') {
	383	+ if (templates[templates.length - 1] === 0) templates.pop()
	384	+ else templates[templates.length - 1]--
	385	+ }
347	386	if (c === '/' && text[i + 1] === '*') {
348	387	const end = text.indexOf('*/', i + 2)
349	388	const stop = end === -1 ? n : end + 2

packages/dtsx/test/bundle-linker.test.tsmodified+14-0

Changes to packages/dtsx/test/bundle-linker.test.ts

		⋯30 linesShow the 30 lines above this hunk@@ -31,4 +31,18 @@ describe('renameIdentifiers', () => {
31	31	'declare function f(options: Options_1, o: { Options: string, x?: Options_1 }): Ns.Options | \'Options\';',
32	32	)
33	33	})
	34	+
	35	+ it('leaves template literal text alone and renames inside its placeholders', () => {
	36	+ const renames = new Map([['Options', 'Options_1']])
	37	+ const text = [
	38	+ 'type A = `Options` | `// Options` | `\\`Options` | `\\${Options}` | Options;',
	39	+ 'type B = `${Options}-Options` | `a${`Options-${Options}`}b` | `${{ Options: 1 } extends Options ? \'x\' : \'y\'}`;',
	40	+ 'type C = Options;',
	41	+ ].join('\n')
	42	+ expect(renameIdentifiers(text, renames)).toBe([
	43	+ 'type A = `Options` | `// Options` | `\\`Options` | `\\${Options}` | Options_1;',
	44	+ 'type B = `${Options_1}-Options` | `a${`Options-${Options_1}`}b` | `${{ Options: 1 } extends Options_1 ? \'x\' : \'y\'}`;',
	45	+ 'type C = Options_1;',
	46	+ ].join('\n'))
	47	+ })
34	48	})

packages/dtsx/test/module-graph.test.tsmodified+52-0

Changes to packages/dtsx/test/module-graph.test.ts

		⋯460 linesShow the 460 lines above this hunk@@ -461,6 +461,58 @@ describe('generate with bundle: true', () => {
461	461	await rm(dir, { recursive: true, force: true })
462	462	})
463	463
	464	+ // Renaming a linked name (`enabled` to the default export's helper, a
	465	+ // colliding `Options` to `Options_1`) also rewrote the same word inside
	466	+ // template literal types, changing what they accept.
	467	+ it('keeps template literal text when renaming', async () => {
	468	+ const dir = await mkdtemp(join(tmpdir(), 'dtsx-bundle-template-'))
	469	+ await writeFiles(dir, {
	470	+ 'src/index.ts': [
	471	+ `import enabled from './flag'`,
	472	+ `export * from './labels'`,
	473	+ `export type Options = 'x' | 'y'`,
	474	+ 'export type Status = `enabled` | `Options`',
	475	+ `export function isEnabled(): number { return Number(enabled) }`,
	476	+ ].join('\n'),
	477	+ 'src/flag.ts': `export default 1`,
	478	+ 'src/labels.ts': [
	479	+ `type Options = 'a' | 'b'`,
	480	+ 'export type Label = `Options-${Options}`',
	481	+ ].join('\n'),
	482	+ 'consumer.ts': [
	483	+ `import { isEnabled, type Label, type Options, type Status } from './dist/index'`,
	484	+ `const status: Status = 'enabled'`,
	485	+ `const other: Status = 'Options'`,
	486	+ `const label: Label = 'Options-a'`,
	487	+ `const option: Options = 'x'`,
	488	+ `export { status, other, label, option, isEnabled }`,
	489	+ ].join('\n'),
	490	+ })
	491	+
	492	+ await generate({
	493	+ cwd: dir,
	494	+ root: 'src',
	495	+ entrypoints: ['index.ts'],
	496	+ outdir: join(dir, 'dist'),
	497	+ clean: false,
	498	+ keepComments: false,
	499	+ tsconfigPath: '',
	500	+ verbose: false,
	501	+ bundle: true,
	502	+ })
	503	+ const bundled = await Bun.file(join(dir, 'dist', 'index.d.ts')).text()
	504	+
	505	+ expect(bundled).toContain('type Status = `enabled` | `Options`;')
	506	+ expect(bundled).toContain('type Label = `Options-${Options_1}`;')
	507	+
	508	+ if (tscAvailable) {
	509	+ const result = runTsc(dir, ['consumer.ts'])
	510	+ expect(result.output).toBe('')
	511	+ expect(result.ok).toBe(true)
	512	+ }
	513	+ await rm(dir, { recursive: true, force: true })
	514	+ })
	515	+
464	516	it('writes one bundled file per entrypoint', async () => {
465	517	await writeFiles(TMP, {
466	518	'src/index.ts': `export * from './router';`,