fix(svelte): expose public store declaration types

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packages/svelte/src/stores/craft.tsmodified+2-1

Changes to packages/svelte/src/stores/craft.ts

		@@ -1,4 +1,5 @@
1	1	import { writable, derived } from 'svelte/store';
	2	+import type { Readable } from 'svelte/store';
2	3
3	4	interface CraftAPI {
4	5	getPlatform(): Promise<{ platform: string; version: string }>;
		⋯13 linesShow the 13 lines above this hunk@@ -18,7 +19,7 @@ declare global {
18	19	}
19	20	}
20	21
21		-function createCraftStore() {
	22	+function createCraftStore(): Readable<CraftAPI | null> {
22	23	const { subscribe, set } = writable<CraftAPI | null>(null);
23	24
24	25	if (typeof window !== 'undefined') {

packages/svelte/src/stores/platform.tsmodified+2-1

Changes to packages/svelte/src/stores/platform.ts

		@@ -1,7 +1,8 @@
1	1	import { writable } from 'svelte/store';
	2	+import type { Readable } from 'svelte/store';
2	3	import { craft } from './craft';
3	4
4		-export function createPlatformStore() {
	5	+export function createPlatformStore(): Readable<{ platform: string; version: string } | null> {
5	6	const { subscribe, set } = writable<{ platform: string; version: string } | null>(null);
6	7
7	8	craft.subscribe(async (_$craft) => {

scripts/svelte-package.test.tsmodified+54-0

Changes to scripts/svelte-package.test.ts

		⋯30 linesShow the 30 lines above this hunk@@ -31,3 +31,57 @@ test('packed Svelte condition resolves outside the workspace', async () => {
31	31	rmSync(temp, { recursive: true, force: true })
32	32	}
33	33	})
	34	+
	35	+test('store declarations expose the public Readable contract', () => {
	36	+ const root = resolve(import.meta.dir, '..')
	37	+ const temp = mkdtempSync(join(tmpdir(), 'craft-svelte-types-'))
	38	+ const run = (args: string[], cwd = temp): void => {
	39	+ const result = Bun.spawnSync([
	40	+ process.execPath, join(root, 'packages/typescript/scripts/tsc.ts'), ...args,
	41	+ ], { cwd, stdout: 'pipe', stderr: 'pipe' })
	42	+ expect(`${result.stdout}\n${result.stderr}`).not.toContain('error TS')
	43	+ expect(result.exitCode).toBe(0)
	44	+ }
	45	+ try {
	46	+ run([
	47	+ '-p', join(root, 'packages/svelte/tsconfig.json'), '--emitDeclarationOnly',
	48	+ '--outDir', join(temp, 'declarations'),
	49	+ ])
	50	+ // Consumers only need Svelte's public store interface. Inferred subscribe
	51	+ // signatures must not leak helper exports from the build-time peer.
	52	+ writeFileSync(join(temp, 'store-contract.d.ts'), `
	53	+declare module 'svelte/store' {
	54	+ export interface Readable<T> {
	55	+ subscribe(run: (value: T) => void, invalidate?: (value?: T) => void): () => void
	56	+ }
	57	+}
	58	+`)
	59	+ writeFileSync(join(temp, 'consumer.mts'), `
	60	+import type { Readable } from 'svelte/store'
	61	+import { craft, isReady } from './declarations/stores/craft.js'
	62	+import { platform, createPlatformStore } from './declarations/stores/platform.js'
	63	+const ready: Readable<boolean> = isReady
	64	+const info: Readable<{ platform: string; version: string } | null> = platform
	65	+const another: typeof info = createPlatformStore()
	66	+const unsubscribe: () => void = craft.subscribe(api => {
	67	+ if (api) {
	68	+ const result: Promise<{ platform: string; version: string }> = api.getPlatform()
	69	+ void result
	70	+ }
	71	+})
	72	+// @ts-expect-error the Craft store is read-only to consumers
	73	+craft.set(null)
	74	+// @ts-expect-error readiness remains boolean
	75	+const wrong: Readable<string> = isReady
	76	+void [ready, info, another, unsubscribe, wrong]
	77	+`)
	78	+ run([
	79	+ 'consumer.mts', 'store-contract.d.ts', '--noEmit', '--strict',
	80	+ '--module', 'nodenext', '--moduleResolution', 'nodenext',
	81	+ '--target', 'esnext', '--ignoreConfig',
	82	+ ])
	83	+ }
	84	+ finally {
	85	+ rmSync(temp, { recursive: true, force: true })
	86	+ }
	87	+}, 60_000)