tdd-start

TDD Mode Activation

Activate TDD Dev Mode for this session. From now on, apply strict Test-Driven Development practices to all coding requests.

Step 1: Detect Configuration First

Before creating the flag file, detect the test command:

1. Check for settings file: Look for .claude/tdd-dev.local.md in project root
2. Auto-detect test command:
   • If package.json exists: Use npm test or check for vitest/jest in devDependencies
   • If pyproject.toml or pytest.ini exists: Use pytest
   • If go.mod exists: Use go test ./...
   • Otherwise: Ask user for test command
3. Read strictness setting: Default to strict if not configured

Step 2: Create TDD Mode Flag File

CRITICAL: Create the flag file that enables hook enforcement.

1. Ensure .claude/ directory exists in project root
2. Create the TDD mode state file at .claude/.tdd-mode-active with the following JSON content:

{
  "active": true,
  "activatedAt": "[current ISO timestamp]",
  "strictness": "strict",
  "testCommand": "[detected or configured test command]"
}

This file signals to hooks that TDD mode is active and stores the detected configuration for use by commands and hooks.

Step 2.5: Initialize TDD Cycle State

CRITICAL: Create the cycle state file that tracks TDD phases.

Create .claude/.tdd-cycle-state with the following JSON content:

{
  "phase": "red",
  "testFilesWritten": [],
  "testsRan": false,
  "testsFailed": false
}

This file tracks the current TDD phase:

• red: Waiting for failing test to be written and run
• green: Test failed, now implement to make it pass
• refactor: Tests passing, safe to refactor

The hooks use this file to enforce the TDD cycle:

• PreToolUse (Write|Edit) blocks source file edits unless phase is "green" or "refactor"
• PostToolUse (Bash) detects test runs and transitions phases automatically

Step 3: Session State

Set the following TDD mode state:

• TDD Mode: ACTIVE (flag file created)
• Strictness: [detected or default: strict]
• Test Command: [detected command]