Add tests for optional props on Svelte components

packages/language-server/test/plugins/typescript/features/DiagnosticsProvider.test.ts

@@ -112,6 +112,24 @@ describe('TypeScript Plugin#DiagnosticsProvider', () => {
 		]);
 	});
 
+	it('properly support optional props on Svelte components', async () => {
+		const { provider, document } = setup('svelteOptional.astro');
+
+		const diagnostics = await provider.getDiagnostics(document);
+
+		expect(diagnostics).to.deep.equal([
+			{
+				code: 2322,
+				message:
+					"Type '{}' is not assignable to type 'IntrinsicAttributes & { notOptional: any; optional?: string; }'.\nProperty 'notOptional' is missing in type '{}' but required in type '{ notOptional: any; optional?: string; }'.",
+				range: Range.create(4, 1, 4, 20),
+				severity: DiagnosticSeverity.Error,
+				source: 'ts',
+				tags: [],
+			},
+		]);
+	});
+
 	it('provide diagnostics for invalid framework components', async () => {
 		const { provider, document } = setup('frameworkComponentError.astro');
 

packages/language-server/test/plugins/typescript/features/HoverProvider.test.ts

@@ -67,7 +67,7 @@ describe('TypeScript Plugin#HoverProvider', () => {
 
 		expect(hoverInfo).to.deep.equal(<Hover>{
 			contents:
-				'```typescript\n(alias) function Sveltecomment(_props: typeof Props): any\nimport Sveltecomment\n```\n---\nMy super Svelte component!',
+				'```typescript\n(alias) function Sveltecomment(_props: typeof Component.props): any\nimport Sveltecomment\n```\n---\nMy super Svelte component!',
 			range: Range.create(4, 1, 4, 14),
 		});
 	});

packages/language-server/test/plugins/typescript/fixtures/diagnostics/SvelteOptionalProps.svelte

@@ -0,0 +1,4 @@
+<script>
+	export const optional = "Hey"
+	export let notOptional
+</script>

packages/language-server/test/plugins/typescript/fixtures/diagnostics/svelteOptional.astro

@@ -0,0 +1,5 @@
+---
+import SvelteOptionalProps from "./SvelteOptionalProps.svelte"
+---
+
+<SvelteOptionalProps></SvelteOptionalProps>