add missing motion tests (#10355)

* add missing motion tests

* fix

---------

Co-authored-by: Rich Harris <[email protected]>

Author: Rich-Harris

packages/svelte/tests/motion/test.ts

@@ -0,0 +1,30 @@
+import { describe, it, assert } from 'vitest';
+import { get } from 'svelte/store';
+import { spring, tweened } from 'svelte/motion';
+
+describe('motion', () => {
+	describe('spring', () => {
+		it('handles initially undefined values', () => {
+			const size = spring();
+
+			size.set(100);
+			assert.equal(get(size), 100);
+		});
+	});
+
+	describe('tweened', () => {
+		it('handles initially undefined values', () => {
+			const size = tweened();
+
+			size.set(100);
+			assert.equal(get(size), 100);
+		});
+
+		it('sets immediately when duration is 0', () => {
+			const size = tweened(0);
+
+			size.set(100, { duration: 0 });
+			assert.equal(get(size), 100);
+		});
+	});
+});

packages/svelte/tsconfig.json

@@ -21,6 +21,7 @@
 			"svelte/compiler": ["./src/compiler/public.d.ts"],
 			"svelte/internal": ["./src/internal/index.js"],
 			"svelte/legacy": ["./src/legacy/legacy-client.js"],
+			"svelte/motion": ["./src/motion/public.d.ts"],
 			"svelte/server": ["./src/server/index.js"],
 			"svelte/store": ["./src/store/public.d.ts"],
 			"#compiler": ["./src/compiler/types/index.d.ts"]