chore: import upstream snapshot with attribution

tools/ui/tests/unit/parse-mcp-server-settings.test.ts

@@ -0,0 +1,144 @@
+import { describe, expect, it, vi } from 'vitest';
+import { parseMcpServerSettings } from '$lib/utils/mcp';
+import { DEFAULT_MCP_CONFIG, MCP_SERVER_ID_PREFIX } from '$lib/constants/mcp';
+
+/**
+ * Tests for the mcpServers settings parser.
+ *
+ * The branch seeds the MCP servers setting with a default value of
+ * `JSON.stringify(RECOMMENDED_MCP_SERVERS)`, so the parser has to be
+ * resilient to anything that may live in the user's localStorage: malformed
+ * JSON, wrong shapes, missing fields, falsy-but-not-zero numbers, and entry
+ * arrays that have been mutated by the user via the settings form.
+ */
+describe('parseMcpServerSettings', () => {
+	it('returns an empty array for falsy or whitespace-only input', () => {
+		expect(parseMcpServerSettings(null)).toEqual([]);
+		expect(parseMcpServerSettings(undefined)).toEqual([]);
+		expect(parseMcpServerSettings('')).toEqual([]);
+		expect(parseMcpServerSettings('   ')).toEqual([]);
+	});
+
+	it('returns an empty array and logs a warning for invalid JSON strings', () => {
+		const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+
+		expect(parseMcpServerSettings('{not-json')).toEqual([]);
+		expect(warn).toHaveBeenCalled();
+
+		warn.mockRestore();
+	});
+
+	it('returns an empty array for valid JSON that is not an array', () => {
+		expect(parseMcpServerSettings('"plain-string"')).toEqual([]);
+		expect(parseMcpServerSettings('{"id":"foo"}')).toEqual([]);
+		expect(parseMcpServerSettings('42')).toEqual([]);
+		expect(parseMcpServerSettings('null')).toEqual([]);
+	});
+
+	it('drops entries with no parseable id and substitutes a stable fallback', () => {
+		const parsed = parseMcpServerSettings(
+			JSON.stringify([{ url: 'https://a.test', enabled: true }, { url: 'https://b.test' }])
+		);
+
+		expect(parsed).toHaveLength(2);
+		expect(parsed[0]?.id).toBe(`${MCP_SERVER_ID_PREFIX}-1`);
+		expect(parsed[1]?.id).toBe(`${MCP_SERVER_ID_PREFIX}-2`);
+	});
+
+	it('reuses the first id when it is present and falls back only for missing ones', () => {
+		const parsed = parseMcpServerSettings(
+			JSON.stringify([
+				{ id: 'custom-1', url: 'https://a.test' },
+				{ url: 'https://b.test' },
+				{ id: 'custom-3', url: 'https://c.test' }
+			])
+		);
+
+		expect(parsed[0]?.id).toBe('custom-1');
+		expect(parsed[1]?.id).toBe(`${MCP_SERVER_ID_PREFIX}-2`);
+		expect(parsed[2]?.id).toBe('custom-3');
+	});
+
+	it('falls back to the configured default requestTimeoutSeconds only for nullish values', () => {
+		const fallback = DEFAULT_MCP_CONFIG.requestTimeoutSeconds;
+
+		const parsed = parseMcpServerSettings(
+			JSON.stringify([
+				{ id: 'a', url: 'https://a.test' },
+				{ id: 'b', url: 'https://b.test', requestTimeoutSeconds: undefined },
+				{ id: 'c', url: 'https://c.test', requestTimeoutSeconds: 0 },
+				{ id: 'd', url: 'https://d.test', requestTimeoutSeconds: 45 }
+			])
+		);
+
+		// The parser uses ?? for timeout fallback, which only triggers on
+		// null/undefined. Explicit 0 is preserved at face value.
+		expect(parsed[0]?.requestTimeoutSeconds).toBe(fallback);
+		expect(parsed[1]?.requestTimeoutSeconds).toBe(fallback);
+		expect(parsed[2]?.requestTimeoutSeconds).toBe(0);
+		expect(parsed[3]?.requestTimeoutSeconds).toBe(45);
+	});
+
+	it('treats whitespace-only headers strings as undefined', () => {
+		const parsed = parseMcpServerSettings(
+			JSON.stringify([
+				{ id: 'a', url: 'https://a.test', headers: '   ' },
+				{ id: 'b', url: 'https://b.test', headers: '{"X-Foo":"bar"}' }
+			])
+		);
+
+		// The parser trims headers and coerces empty/whitespace to undefined.
+		expect(parsed[0]?.headers).toBeUndefined();
+		expect(parsed[1]?.headers).toBe('{"X-Foo":"bar"}');
+	});
+
+	it('defaults coercion for booleans (undefined -> false, true -> true)', () => {
+		const parsed = parseMcpServerSettings(
+			JSON.stringify([
+				{ id: 'a', url: 'https://a.test' },
+				{ id: 'b', url: 'https://b.test', enabled: true },
+				{ id: 'c', url: 'https://c.test', enabled: false },
+				{ id: 'd', url: 'https://d.test', useProxy: true }
+			])
+		);
+
+		expect(parsed[0]?.enabled).toBe(false);
+		expect(parsed[1]?.enabled).toBe(true);
+		expect(parsed[2]?.enabled).toBe(false);
+		expect(parsed[0]?.useProxy).toBe(false);
+		expect(parsed[3]?.useProxy).toBe(true);
+	});
+
+	it('preserves input order when mapping entries', () => {
+		const source = [
+			{ id: 'gamma', url: 'https://c.test' },
+			{ id: 'alpha', url: 'https://a.test' },
+			{ id: 'beta', url: 'https://b.test' }
+		];
+
+		const parsed = parseMcpServerSettings(JSON.stringify(source));
+
+		expect(parsed.map((entry) => entry.id)).toEqual(['gamma', 'alpha', 'beta']);
+	});
+
+	it('passes non-string raw input through the JSON-equality path', () => {
+		const parsed = parseMcpServerSettings([
+			{ id: 'a', url: 'https://a.test' },
+			{ id: 'b', url: 'https://b.test', enabled: true }
+		]);
+
+		expect(parsed).toHaveLength(2);
+		expect(parsed[0]?.id).toBe('a');
+		expect(parsed[1]?.enabled).toBe(true);
+	});
+
+	it('coerces non-string url values to an empty string rather than throwing', () => {
+		const parsed = parseMcpServerSettings(
+			JSON.stringify([{ id: 'a', url: 42 }, { id: 'b' }, { id: 'c', url: 'https://c.test' }])
+		);
+
+		expect(parsed[0]?.url).toBe('');
+		expect(parsed[1]?.url).toBe('');
+		expect(parsed[2]?.url).toBe('https://c.test');
+	});
+});