fix: resolve test failures by implementing proper dependency injection for resource handlers

- Add setTestExecutor/clearTestExecutor functions for test dependency injection
- Fix TypeScript issues by replacing Function types with CommandExecutor
- Fix ESLint/Prettier formatting violations
- Enable proper mock executor injection in resource tests
- Maintain backward compatibility with production resource handling

Co-authored-by: Cameron Cooke <cameroncooke@users.noreply.github.com>

Author: claude[bot]

src/core/__tests__/resources.test.ts

@@ -6,13 +6,18 @@ import {
   getAvailableResources,
   supportsResources,
   RESOURCE_URIS,
+  setTestExecutor,
+  clearTestExecutor,
 } from '../resources.js';
-import { createMockExecutor } from '../../utils/command.js';
+import { createMockExecutor, CommandExecutor } from '../../utils/command.js';
 
 describe('resources', () => {
   let mockServer: McpServer;
 
   beforeEach(() => {
+    // Clear any test executor from previous tests
+    clearTestExecutor();
+
     // Create a mock MCP server using simple object structure
     mockServer = {
       resource: () => {},
@@ -62,15 +67,19 @@ describe('resources', () => {
       let capturedDescription: string | undefined;
       let capturedOptions: { mimeType: string } | undefined;
       let capturedHandler:
-        | ((executor?: any) => Promise<{ contents: Array<{ type: 'text'; text: string }> }>)
+        | ((
+            executor?: CommandExecutor,
+          ) => Promise<{ contents: Array<{ type: 'text'; text: string }> }>)
         | undefined;
 
       // Capture the registration call parameters
       mockServer.resource = (
         uri: string,
         description: string,
         options: { mimeType: string },
-        handler: (executor?: any) => Promise<{ contents: Array<{ type: 'text'; text: string }> }>,
+        handler: (
+          executor?: CommandExecutor,
+        ) => Promise<{ contents: Array<{ type: 'text'; text: string }> }>,
       ) => {
         capturedUri = uri;
         capturedDescription = description;
@@ -101,15 +110,17 @@ describe('resources', () => {
 
   describe('Simulators Resource Handler', () => {
     let resourceHandler: (
-      executor?: any,
+      executor?: CommandExecutor,
     ) => Promise<{ contents: Array<{ type: 'text'; text: string }> }>;
 
     beforeEach(() => {
       mockServer.resource = (
         _uri: string,
         _description: string,
         _options: { mimeType: string },
-        handler: (executor?: any) => Promise<{ contents: Array<{ type: 'text'; text: string }> }>,
+        handler: (
+          executor?: CommandExecutor,
+        ) => Promise<{ contents: Array<{ type: 'text'; text: string }> }>,
       ) => {
         resourceHandler = handler;
       };

src/core/resources.ts

@@ -16,6 +16,12 @@ import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
 import { log, getDefaultCommandExecutor, CommandExecutor } from '../utils/index.js';
 import { list_simsLogic } from '../plugins/simulator-shared/list_sims.js';
 
+/**
+ * Test executor injection for dependency injection during testing
+ * This allows tests to override the executor without modifying production code
+ */
+let testExecutor: CommandExecutor | undefined;
+
 /**
  * Resource URI schemes supported by XcodeBuildMCP
  */
@@ -33,6 +39,21 @@ export function supportsResources(): boolean {
   return true;
 }
 
+/**
+ * Set test executor for dependency injection (testing only)
+ * @param executor Test executor to use
+ */
+export function setTestExecutor(executor: CommandExecutor): void {
+  testExecutor = executor;
+}
+
+/**
+ * Clear test executor (testing only)
+ */
+export function clearTestExecutor(): void {
+  testExecutor = undefined;
+}
+
 /**
  * Resource handler for simulator data
  * Uses existing list_simsLogic to maintain consistency
@@ -43,8 +64,9 @@ async function handleSimulatorsResource(executor?: CommandExecutor): Promise<{
   try {
     log('info', 'Processing simulators resource request');
 
-    // Use existing logic with dependency injection
-    const result = await list_simsLogic({}, executor || getDefaultCommandExecutor());
+    // Use provided executor, or test executor, or default executor (in that order)
+    const effectiveExecutor = executor || testExecutor || getDefaultCommandExecutor();
+    const result = await list_simsLogic({}, effectiveExecutor);
 
     if (result.isError) {
       throw new Error(result.content[0]?.text || 'Failed to retrieve simulator data');
@@ -80,7 +102,8 @@ async function handleSimulatorsResource(executor?: CommandExecutor): Promise<{
 export function registerResources(server: McpServer): void {
   log('info', 'Registering MCP resources');
 
-  // Register simulators resource with wrapper to support dependency injection in tests
+  // Register simulators resource with wrapper that supports test executor injection
+  // The wrapper allows tests to pass an executor parameter for dependency injection
   server.resource(
     RESOURCE_URIS.SIMULATORS,
     'Available iOS simulators with their UUIDs and states',