feat: abillity to configure "Start Dev Server" command in project settings

apps/server/src/routes/worktree/index.ts

@@ -134,7 +134,7 @@ export function createWorktreeRoutes(
   router.post(
     '/start-dev',
     validatePathParams('projectPath', 'worktreePath'),
-    createStartDevHandler()
+    createStartDevHandler(settingsService)
   );
   router.post('/stop-dev', createStopDevHandler());
   router.post('/list-dev-servers', createListDevServersHandler());

apps/server/src/routes/worktree/routes/start-dev.ts

@@ -1,16 +1,22 @@
 /**
  * POST /start-dev endpoint - Start a dev server for a worktree
  *
- * Spins up a development server (npm run dev) in the worktree directory
- * on a unique port, allowing preview of the worktree's changes without
- * affecting the main dev server.
+ * Spins up a development server in the worktree directory on a unique port,
+ * allowing preview of the worktree's changes without affecting the main dev server.
+ *
+ * If a custom devCommand is configured in project settings, it will be used.
+ * Otherwise, auto-detection based on package manager (npm/yarn/pnpm/bun run dev) is used.
  */
 
 import type { Request, Response } from 'express';
+import type { SettingsService } from '../../../services/settings-service.js';
 import { getDevServerService } from '../../../services/dev-server-service.js';
 import { getErrorMessage, logError } from '../common.js';
+import { createLogger } from '@automaker/utils';
+
+const logger = createLogger('start-dev');
 
-export function createStartDevHandler() {
+export function createStartDevHandler(settingsService?: SettingsService) {
   return async (req: Request, res: Response): Promise<void> => {
     try {
       const { projectPath, worktreePath } = req.body as {
@@ -34,8 +40,25 @@ export function createStartDevHandler() {
         return;
       }
 
+      // Get custom dev command from project settings (if configured)
+      let customCommand: string | undefined;
+      if (settingsService) {
+        const projectSettings = await settingsService.getProjectSettings(projectPath);
+        const devCommand = projectSettings?.devCommand?.trim();
+        if (devCommand) {
+          customCommand = devCommand;
+          logger.debug(`Using custom dev command from project settings: ${customCommand}`);
+        } else {
+          logger.debug('No custom dev command configured, using auto-detection');
+        }
+      }
+
       const devServerService = getDevServerService();
-      const result = await devServerService.startDevServer(projectPath, worktreePath);
+      const result = await devServerService.startDevServer(
+        projectPath,
+        worktreePath,
+        customCommand
+      );
 
       if (result.success && result.result) {
         res.json({

apps/server/src/services/dev-server-service.ts

@@ -273,12 +273,56 @@ class DevServerService {
     }
   }
 
+  /**
+   * Parse a custom command string into cmd and args
+   * Handles quoted strings with spaces (e.g., "my command" arg1 arg2)
+   */
+  private parseCustomCommand(command: string): { cmd: string; args: string[] } {
+    const tokens: string[] = [];
+    let current = '';
+    let inQuote = false;
+    let quoteChar = '';
+
+    for (let i = 0; i < command.length; i++) {
+      const char = command[i];
+
+      if (inQuote) {
+        if (char === quoteChar) {
+          inQuote = false;
+        } else {
+          current += char;
+        }
+      } else if (char === '"' || char === "'") {
+        inQuote = true;
+        quoteChar = char;
+      } else if (char === ' ') {
+        if (current) {
+          tokens.push(current);
+          current = '';
+        }
+      } else {
+        current += char;
+      }
+    }
+
+    if (current) {
+      tokens.push(current);
+    }
+
+    const [cmd, ...args] = tokens;
+    return { cmd: cmd || '', args };
+  }
+
   /**
    * Start a dev server for a worktree
+   * @param projectPath - The project root path
+   * @param worktreePath - The worktree directory path
+   * @param customCommand - Optional custom command to run instead of auto-detected dev command
    */
   async startDevServer(
     projectPath: string,
-    worktreePath: string
+    worktreePath: string,
+    customCommand?: string
   ): Promise<{
     success: boolean;
     result?: {
@@ -311,22 +355,41 @@ class DevServerService {
       };
     }
 
-    // Check for package.json
-    const packageJsonPath = path.join(worktreePath, 'package.json');
-    if (!(await this.fileExists(packageJsonPath))) {
-      return {
-        success: false,
-        error: `No package.json found in: ${worktreePath}`,
-      };
-    }
+    // Determine the dev command to use
+    let devCommand: { cmd: string; args: string[] };
 
-    // Get dev command
-    const devCommand = await this.getDevCommand(worktreePath);
-    if (!devCommand) {
-      return {
-        success: false,
-        error: `Could not determine dev command for: ${worktreePath}`,
-      };
+    // Normalize custom command: trim whitespace and treat empty strings as undefined
+    const normalizedCustomCommand = customCommand?.trim();
+
+    if (normalizedCustomCommand) {
+      // Use the provided custom command
+      devCommand = this.parseCustomCommand(normalizedCustomCommand);
+      if (!devCommand.cmd) {
+        return {
+          success: false,
+          error: 'Invalid custom command: command cannot be empty',
+        };
+      }
+      logger.debug(`Using custom command: ${normalizedCustomCommand}`);
+    } else {
+      // Check for package.json when auto-detecting
+      const packageJsonPath = path.join(worktreePath, 'package.json');
+      if (!(await this.fileExists(packageJsonPath))) {
+        return {
+          success: false,
+          error: `No package.json found in: ${worktreePath}`,
+        };
+      }
+
+      // Get dev command from package manager detection
+      const detectedCommand = await this.getDevCommand(worktreePath);
+      if (!detectedCommand) {
+        return {
+          success: false,
+          error: `Could not determine dev command for: ${worktreePath}`,
+        };
+      }
+      devCommand = detectedCommand;
     }
 
     // Find available port

apps/server/src/services/settings-service.ts

@@ -837,6 +837,20 @@ export class SettingsService {
       delete updated.defaultFeatureModel;
     }
 
+    // Handle devCommand special cases:
+    // - null means delete the key (use auto-detection)
+    // - string means custom command
+    if ('devCommand' in updates && updates.devCommand === null) {
+      delete updated.devCommand;
+    }
+
+    // Handle testCommand special cases:
+    // - null means delete the key (use auto-detection)
+    // - string means custom command
+    if ('testCommand' in updates && updates.testCommand === null) {
+      delete updated.testCommand;
+    }
+
     await writeSettingsJson(settingsPath, updated);
     logger.info(`Project settings updated for ${projectPath}`);