not workng yet

package.json

@@ -49,6 +49,7 @@
         "eslint-config-prettier": "^9.1.0",
         "eslint-plugin-prettier": "^5.1.1",
         "eslint-plugin-svelte": "^2.36.0",
+        "fast-check": "^3.23.2",
         "globals": "^15.0.0",
         "jsdom": "^24.0.0",
         "lodash": "^4.17.21",

packages/ui-components/src/__tests__/handleShareChoices.test.ts

@@ -1,6 +1,7 @@
 import { describe, it, expect, vi, beforeEach } from 'vitest';
 import { handleShareChoices } from '../lib/services/handleShareChoices';
 import type { DotrainOrderGui } from '@rainlanguage/orderbook/js_api';
+import fc from 'fast-check';
 
 describe('handleShareChoices', () => {
 	beforeEach(() => {
@@ -50,3 +51,42 @@ describe('handleShareChoices', () => {
 		expect(navigator.clipboard.writeText).toHaveBeenCalledWith('http://example.com/?state=');
 	});
 });
+
+describe('property-based tests', () => {
+	beforeEach(() => {
+		Object.assign(navigator, {
+			clipboard: {
+				writeText: vi.fn()
+			}
+		});
+
+		vi.mock('$app/stores', () => ({
+			page: {
+				subscribe: vi.fn((fn) => {
+					fn({ url: new URL('http://example.com') });
+					return () => {};
+				})
+			}
+		}));
+	});
+
+	it('should always create valid URLs with any state string', async () => {
+		await fc.assert(
+			fc.asyncProperty(fc.string(), async (state) => {
+				const mockGui = {
+					serializeState: vi.fn().mockReturnValue(state)
+				};
+
+				await handleShareChoices(mockGui as unknown as DotrainOrderGui);
+
+				const clipboardText = (navigator.clipboard.writeText as any).mock.calls[0][0];
+				const url = new URL(clipboardText);
+
+				// Property: URL should always be valid and contain the state parameter
+				expect(url.searchParams.has('state')).toBe(true);
+				// Compare with the encoded state value
+				expect(url.searchParams.get('state')).toBe(encodeURIComponent(state));
+			})
+		);
+	});
+});