Expand tilde (~) in config paths like derivedDataPath

src/mcp/tools/device/__tests__/list_devices.test.ts

@@ -225,7 +225,7 @@ describe('list_devices plugin (device-shared)', () => {
           },
         ],
         nextStepParams: {
-          build_device: { scheme: 'SCHEME', deviceId: 'DEVICE_UDID' },
+          build_device: { scheme: 'SCHEME' },
           build_run_device: { scheme: 'SCHEME', deviceId: 'DEVICE_UDID' },
           test_device: { scheme: 'SCHEME', deviceId: 'DEVICE_UDID' },
           get_device_app_path: { scheme: 'SCHEME' },

src/mcp/tools/device/list_devices.ts

@@ -399,7 +399,7 @@ export async function list_devicesLogic(
         'Before running build/run/test/UI automation tools, set the desired device identifier in session defaults.\n';
 
       nextStepParams = {
-        build_device: { scheme: 'SCHEME', deviceId: 'DEVICE_UDID' },
+        build_device: { scheme: 'SCHEME' },
         build_run_device: { scheme: 'SCHEME', deviceId: 'DEVICE_UDID' },
         test_device: { scheme: 'SCHEME', deviceId: 'DEVICE_UDID' },
         get_device_app_path: { scheme: 'SCHEME' },

src/utils/__tests__/build-utils.test.ts

@@ -387,5 +387,41 @@ describe('build-utils Sentry Classification', () => {
       expect(capturedCommand).toContain(expectedDerivedDataPath);
       expect(capturedOptions).toEqual({ cwd: path.dirname(expectedProjectPath) });
     });
+
+    it('should expand tilde in derivedDataPath to home directory', async () => {
+      let capturedCommand: string[] | undefined;
+      const mockExecutor = createMockExecutor({
+        success: true,
+        output: 'BUILD SUCCEEDED',
+        exitCode: 0,
+        onExecute: (command) => {
+          capturedCommand = command;
+        },
+      });
+
+      const { homedir } = await import('os');
+      const expectedDerivedDataPath = path.join(homedir(), '.derivedData/test');
+
+      await executeXcodeBuildCommand(
+        {
+          scheme: 'TestScheme',
+          configuration: 'Debug',
+          projectPath: '/path/to/project.xcodeproj',
+          derivedDataPath: '~/.derivedData/test',
+        },
+        {
+          platform: XcodePlatform.iOSSimulator,
+          simulatorName: 'iPhone 17 Pro',
+          useLatestOS: true,
+          logPrefix: 'iOS Simulator Build',
+        },
+        false,
+        'build',
+        mockExecutor,
+      );
+
+      expect(capturedCommand).toBeDefined();
+      expect(capturedCommand).toContain(expectedDerivedDataPath);
+    });
   });
 });

src/utils/__tests__/project-config.test.ts

@@ -1,5 +1,6 @@
 import { describe, expect, it } from 'vitest';
 import path from 'node:path';
+import { homedir } from 'node:os';
 import { parse as parseYaml } from 'yaml';
 import { createMockFileSystemExecutor } from '../../test-utils/mock-executors.ts';
 import {
@@ -187,6 +188,25 @@ describe('project-config', () => {
       );
     });
 
+    it('should expand tilde in derivedDataPath and other path fields', async () => {
+      const yaml = [
+        'schemaVersion: 1',
+        'sessionDefaults:',
+        '  workspacePath: "./App.xcworkspace"',
+        '  derivedDataPath: "~/.derivedData/myproject"',
+        '',
+      ].join('\n');
+
+      const { fs } = createFsFixture({ exists: true, readFile: yaml });
+      const result = await loadProjectConfig({ fs, cwd });
+
+      if (!result.found) throw new Error('expected config to be found');
+
+      const defaults = result.config.sessionDefaults ?? {};
+      expect(defaults.derivedDataPath).toBe(path.join(homedir(), '.derivedData', 'myproject'));
+      expect(defaults.workspacePath).toBe(path.join(cwd, 'App.xcworkspace'));
+    });
+
     it('should return an error result when schemaVersion is unsupported', async () => {
       const yaml = ['schemaVersion: 2', 'sessionDefaults:', '  scheme: "App"', ''].join('\n');
       const { fs } = createFsFixture({ exists: true, readFile: yaml });

src/utils/build-utils.ts

@@ -32,8 +32,15 @@ import {
 } from './xcodemake.ts';
 import { sessionStore } from './session-store.ts';
 import path from 'path';
+import { homedir } from 'os';
 
 function resolvePathFromCwd(pathValue: string): string {
+  if (pathValue === '~') {
+    return homedir();
+  }
+  if (pathValue.startsWith('~/')) {
+    return path.join(homedir(), pathValue.slice(2));
+  }
   if (path.isAbsolute(pathValue)) {
     return pathValue;
   }

src/utils/project-config.ts

@@ -1,4 +1,5 @@
 import path from 'node:path';
+import { homedir } from 'node:os';
 import { fileURLToPath } from 'node:url';
 import { parse as parseYaml, stringify as stringifyYaml } from 'yaml';
 import type { FileSystemExecutor } from './FileSystemExecutor.ts';
@@ -125,6 +126,14 @@ function normalizePathValue(value: string, cwd: string): string {
     return fileUrlPath;
   }
 
+  if (value === '~') {
+    return homedir();
+  }
+
+  if (value.startsWith('~/')) {
+    return path.join(homedir(), value.slice(2));
+  }
+
   if (path.isAbsolute(value)) {
     return value;
   }