Test Runner MCP

Instructions

Implementation Reference

• src/index.ts:181-253 (handler)

  Main handler for the 'run_tests' tool via CallToolRequestSchema. Validates input, orchestrates test execution, result parsing, reporting, and response formatting.
  this.server.setRequestHandler(CallToolRequestSchema, async (request: Request) => { if (!request.params?.name) { throw new Error('Missing tool name'); } if (request.params.name !== 'run_tests') { throw new Error(`Unknown tool: ${request.params.name}`); } if (!request.params.arguments) { throw new Error('Missing tool arguments'); } const args = request.params.arguments as unknown as TestRunArguments; if (!this.isValidTestRunArguments(args)) { throw new Error('Invalid test run arguments'); } const { command, workingDir, framework, outputDir = 'test_reports', timeout = DEFAULT_TIMEOUT, env, securityOptions } = args; // Validate command against security rules if (framework === 'generic') { const validation = validateCommand(command, securityOptions); if (!validation.isValid) { throw new Error(`Command validation failed: ${validation.reason}`); } } debug('Running tests with args:', { command, workingDir, framework, outputDir, timeout, env }); // Create output directory const resultDir = join(workingDir, outputDir); await mkdir(resultDir, { recursive: true }); try { // Run tests with timeout const { stdout, stderr } = await this.executeTestCommand(command, workingDir, framework, resultDir, timeout, env, securityOptions); // Save raw output await writeFile(join(resultDir, 'test_output.log'), stdout); if (stderr) { await writeFile(join(resultDir, 'test_errors.log'), stderr); } // Parse the test results using the appropriate parser try { const results = this.parseTestResults(framework, stdout, stderr); // Write parsed results to file await writeFile(join(resultDir, 'test_results.json'), JSON.stringify(results, null, 2)); // Create a summary file const summaryContent = this.generateSummary(results); await writeFile(join(resultDir, 'summary.txt'), summaryContent); } catch (parseError) { debug('Error parsing test results:', parseError); // Still continue even if parsing fails } return { content: [ { type: 'text', text: stdout + (stderr ? '\n' + stderr : ''), }, ], isError: stdout.includes('failed') || stdout.includes('[E]') || stderr.length > 0, }; } catch (error) { const errorMessage = error instanceof Error ? error.message : 'Unknown error occurred'; debug('Test execution failed:', errorMessage); throw new Error(`Test execution failed: ${errorMessage}`); } });
• src/index.ts:45-100 (schema)

  Input schema definition for the 'run_tests' tool, specifying required parameters and types for command, working directory, framework, and optional fields.
  inputSchema: { type: 'object', properties: { command: { type: 'string', description: 'Test command to execute (e.g., "bats tests/*.bats")', }, workingDir: { type: 'string', description: 'Working directory for test execution', }, framework: { type: 'string', enum: ['bats', 'pytest', 'flutter', 'jest', 'go', 'rust', 'generic'], description: 'Testing framework being used', }, outputDir: { type: 'string', description: 'Directory to store test results', }, timeout: { type: 'number', description: 'Test execution timeout in milliseconds (default: 300000)', }, env: { type: 'object', description: 'Environment variables for test execution', additionalProperties: { type: 'string' } }, securityOptions: { type: 'object', description: 'Security options for command execution', properties: { allowSudo: { type: 'boolean', description: 'Allow sudo commands (default: false)' }, allowSu: { type: 'boolean', description: 'Allow su commands (default: false)' }, allowShellExpansion: { type: 'boolean', description: 'Allow shell expansion like $() or backticks (default: true)' }, allowPipeToFile: { type: 'boolean', description: 'Allow pipe to file operations (default: false)' } } } }, required: ['command', 'workingDir', 'framework'], },
• src/index.ts:42-102 (registration)

  Registration of the 'run_tests' tool in the MCP server capabilities.
  run_tests: { name: 'run_tests', description: 'Run tests and capture output', inputSchema: { type: 'object', properties: { command: { type: 'string', description: 'Test command to execute (e.g., "bats tests/*.bats")', }, workingDir: { type: 'string', description: 'Working directory for test execution', }, framework: { type: 'string', enum: ['bats', 'pytest', 'flutter', 'jest', 'go', 'rust', 'generic'], description: 'Testing framework being used', }, outputDir: { type: 'string', description: 'Directory to store test results', }, timeout: { type: 'number', description: 'Test execution timeout in milliseconds (default: 300000)', }, env: { type: 'object', description: 'Environment variables for test execution', additionalProperties: { type: 'string' } }, securityOptions: { type: 'object', description: 'Security options for command execution', properties: { allowSudo: { type: 'boolean', description: 'Allow sudo commands (default: false)' }, allowSu: { type: 'boolean', description: 'Allow su commands (default: false)' }, allowShellExpansion: { type: 'boolean', description: 'Allow shell expansion like $() or backticks (default: true)' }, allowPipeToFile: { type: 'boolean', description: 'Allow pipe to file operations (default: false)' } } } }, required: ['command', 'workingDir', 'framework'], }, }, },
• src/index.ts:312-393 (helper)

  Helper function that executes the test command using node:child_process.spawn, manages timeout, environment sanitization, stdout/stderr capture, and framework-specific configurations.
  private async executeTestCommand( command: string, workingDir: string, framework: Framework, resultDir: string, timeout: number, env?: Record<string, string>, securityOptions?: Partial<SecurityOptions> ): Promise<{ stdout: string; stderr: string }> { return new Promise((resolve, reject) => { const timer = setTimeout(() => { reject(new Error('Test execution timed out')); }, timeout); // Split command into executable and args const parts = command.split(' '); const cmd = parts[0]; const cmdArgs = parts.slice(1); debug('Executing command:', { cmd, cmdArgs, workingDir }); // Sanitize environment variables for security const safeEnv = sanitizeEnvironmentVariables(env); const spawnOptions: SpawnOptions = { cwd: workingDir, env: { ...process.env, ...safeEnv }, shell: true, }; // Add framework-specific environment if needed if (framework === 'flutter') { spawnOptions.env = { ...spawnOptions.env, ...this.getFlutterEnv() }; try { this.verifyFlutterInstallation(spawnOptions); } catch (error) { clearTimeout(timer); reject(error); return; } } else if (framework === 'rust') { // Ensure RUST_BACKTRACE is set for better error reporting spawnOptions.env = { ...spawnOptions.env, RUST_BACKTRACE: '1' }; } const childProcess = spawn(cmd, cmdArgs, spawnOptions); let stdout = ''; let stderr = ''; childProcess.stdout?.on('data', (data: Buffer) => { const chunk = data.toString(); stdout += chunk; debug('stdout chunk:', chunk); }); childProcess.stderr?.on('data', (data: Buffer) => { const chunk = data.toString(); stderr += chunk; debug('stderr chunk:', chunk); }); childProcess.on('error', (error: Error) => { debug('Process error:', error); clearTimeout(timer); reject(error); }); childProcess.on('close', async (code: number | null) => { clearTimeout(timer); debug('Process closed with code:', code); resolve({ stdout, stderr }); }); }); }
• src/index.ts:111-113 (helper)

  Helper method to parse test results using the framework-specific parser from parsers/index.js.
  parseTestResults(framework: Framework, stdout: string, stderr: string): ParsedResults { return TestParserFactory.parseTestResults(framework, stdout, stderr); }