ReviewOS
Reload

also looking at this

stacks/dtsx

fix(extractor): keep the heritage clause of an anonymous default class

#3124
Open mkantautas wants to merge fix/anonymous-class-heritage into main
2 files +103 -1
packages/dtsx/src/extractor/scanner.tsmodified+10-1
@@ -2607,7 +2607,16 @@ function scanDeclarationsInternal(_source: string, _filename: string, _keepComme
26072607 pos += 5 // skip 'class'
26082608 skipWhitespaceAndComments()
26092609
2610 const name = readIdent() || 'AnonymousClass'
2610 // `export default class extends Base {}` has no name: `extends`, or
2611 // `implements` before a type, begins its heritage clause, as TypeScript
2612 // reads it. Such a class gets a helper name the file does not use, as a
2613 // default-exported expression does.
2614 const isAnonymous = isDefault && (matchWord('extends') || (matchWord('implements') && isIdentStart(peekAfterWord('implements'))))
2615 let name = isAnonymous ? '' : (readIdent() || 'AnonymousClass')
2616 if (!name) {
2617 name = '__dtsx_default_class__'
2618 for (let suffix = 1; source.includes(name); suffix++) name = `__dtsx_default_class_${suffix}__`
2619 }
26112620 skipWhitespaceAndComments()
26122621
26132622 const generics = extractGenerics()
packages/dtsx/test/anonymous-default-class.test.tsadded+93-0
@@ -0,0 +1,93 @@
1/**
2 * An anonymous default-exported class with a heritage clause lost it, and its
3 * members with it:
4 *
5 * export default class extends Base { c = 2 }
6 *
7 * emitted `export default class extends {}`, which does not parse.
8 * `extractClass` read `extends` (or `implements`) as the class name. The class
9 * now gets a helper name, `__dtsx_default_class__`, as a default-exported
10 * expression gets `__dtsx_default_export__`.
11 */
12import { describe, expect, it } from 'bun:test'
13import { mkdir, mkdtemp, readFile, rm, writeFile } from 'node:fs/promises'
14import { tmpdir } from 'node:os'
15import { join } from 'node:path'
16import { generate } from '../src/generator'
17import { runTsc } from './helpers/tsc'
18import { processCode } from './test-utils'
19
20/** Type-check `consumer` against the generated declarations as `./index`. */
21async function checkConsumer(dts: string, consumer: string): Promise<string> {
22 const dir = await mkdtemp(join(tmpdir(), 'dtsx-anonymous-class-'))
23 try {
24 await writeFile(join(dir, 'index.d.ts'), dts)
25 await writeFile(join(dir, 'use.ts'), consumer)
26 return runTsc(dir, ['index.d.ts', 'use.ts']).output
27 }
28 finally {
29 await rm(dir, { recursive: true, force: true })
30 }
31}
32
33describe('anonymous default class with a heritage clause', () => {
34 it.each([
35 [
36 'extends',
37 'class Base { b = 1 }\nexport default class extends Base { c = 2 }\n',
38 'export default class __dtsx_default_class__ extends Base {',
39 'import C from \'./index\'\nconst c = new C()\nconst n: number = c.b + c.c\nexport {}\n',
40 ],
41 [
42 'implements',
43 'interface Named { name(): string }\nexport default class implements Named { name(): string { return \'x\' } }\n',
44 'export default class __dtsx_default_class__ implements Named {',
45 'import C from \'./index\'\nconst s: string = new C().name()\nexport {}\n',
46 ],
47 [
48 'abstract, implements',
49 'export default abstract class implements Iterable<number> { abstract [Symbol.iterator](): Iterator<number> }\n',
50 'export default abstract class __dtsx_default_class__ implements Iterable<number> {',
51 'import C from \'./index\'\nexport class D extends C { *[Symbol.iterator](): Iterator<number> { yield 1 } }\nconst all: number[] = [...new D()]\n',
52 ],
53 [
54 'generic, extends',
55 'class Box<T> { value!: T }\nexport default class<T> extends Box<T> { label = \'\' }\n',
56 'export default class AnonymousClass<T> extends Box<T> {',
57 'import C from \'./index\'\nconst c = new C<number>()\nconst n: number = c.value\nconst s: string = c.label\nexport {}\n',
58 ],
59 [
60 'beside a class named AnonymousClass',
61 'interface Marker {}\nexport class AnonymousClass { tag = \'real\' }\nexport default class implements Marker { id = 1 }\n',
62 'export default class __dtsx_default_class__ implements Marker {',
63 'import C, { AnonymousClass } from \'./index\'\nconst n: number = new C().id\nconst s: string = new AnonymousClass().tag\nexport {}\n',
64 ],
65 ])('keeps the clause and the members: %s', async (_label, code, header, consumer) => {
66 const output = processCode(code)
67 expect(output).toContain(header)
68 expect(await checkConsumer(output, consumer)).toBe('')
69 })
70
71 it.each([
72 ['ambient class', 'export declare class implements { c: number }\n', 'export declare class implements {'],
73 ['default class', 'export default class implements { c = 1 }\n', 'export default class implements {'],
74 ])('keeps a class named implements: %s', (_label, code, header) => {
75 expect(processCode(code)).toContain(header)
76 })
77
78 it('keeps the clause in a bundle', async () => {
79 const cwd = await mkdtemp(join(tmpdir(), 'dtsx-anonymous-class-bundle-'))
80 try {
81 await mkdir(join(cwd, 'src'))
82 await writeFile(join(cwd, 'src', 'index.ts'), 'class Base { b = 1 }\nexport default class extends Base { c = 2 }\nexport * from \'./other\'\n')
83 await writeFile(join(cwd, 'src', 'other.ts'), 'export class AnonymousClass { real = \'yes\' }\nexport type Label = `AnonymousClass-${string}`\n')
84 await generate({ cwd, root: 'src', outdir: 'dist', entrypoints: ['index.ts'], bundle: true, clean: false, keepComments: false })
85 expect(await readFile(join(cwd, 'dist', 'index.d.ts'), 'utf8')).toContain('class __dtsx_default_class__ extends Base {')
86 await writeFile(join(cwd, 'dist', 'use.ts'), 'import C, { AnonymousClass, type Label } from \'./index\'\nconst n: number = new C().b + new C().c\nconst real: string = new AnonymousClass().real\nconst label: Label = \'AnonymousClass-ok\'\nexport {}\n')
87 expect(runTsc(join(cwd, 'dist'), ['index.d.ts', 'use.ts']).output).toBe('')
88 }
89 finally {
90 await rm(cwd, { recursive: true, force: true })
91 }
92 })
93})