Add comprehensive tests for validation and transformation functions

.c8rc.json

@@ -0,0 +1,8 @@
+{
+  "all": true,
+  "include": ["src/**/*.js"],
+  "exclude": ["src/schemas/dereferenceSchemas.js"],
+  "reporter": ["text", "lcov", "json", "json-summary"],
+  "report-dir": "coverage",
+  "check-coverage": false
+}

.claude/skills/tdd-coverage/SKILL.md

@@ -0,0 +1,161 @@
+# TDD and Coverage Skill
+
+**Type:** Rigid (follow exactly)
+
+## When to Use
+
+Use this skill when:
+- Creating new functionality
+- Modifying existing code
+- Fixing bugs
+- Refactoring
+
+## Mandatory Process
+
+### 1. Test First (TDD)
+
+Before writing or modifying any implementation code:
+
+1. **Write the test(s)** that describe the expected behavior
+2. **Run the test** - it should FAIL (red)
+3. **Write the implementation** to make the test pass
+4. **Run the test** - it should PASS (green)
+5. **Refactor** if needed, keeping tests passing
+
+### 2. Coverage Verification
+
+After any code change:
+
+```bash
+# Run tests with coverage
+npm run test:coverage
+
+# Verify coverage hasn't decreased
+npm run test:coverage:ratchet
+```
+
+**Coverage must not decrease.** If ratchet check fails:
+1. Add tests for uncovered code
+2. Re-run coverage until ratchet passes
+
+### 3. Coverage Thresholds
+
+Current thresholds are in `coverage-thresholds.json`. These values must only increase:
+
+| Metric | Threshold |
+|--------|-----------|
+| Lines | 100% |
+| Statements | 100% |
+| Functions | 100% |
+| Branches | 100% |
+
+### 4. Test Location
+
+| Code | Test File |
+|------|-----------|
+| `src/validate.js` | `test/validate.test.js` |
+| `src/resolvePaths.js` | `test/resolvePaths.test.js` |
+| `src/files.js` | `test/files.test.js` |
+| Schema validation | `test/schema.test.js` |
+
+### 5. Test Structure Pattern
+
+```javascript
+const sinon = require("sinon");
+
+(async () => {
+  const { expect } = await import("chai");
+  const { functionUnderTest } = require("../src/module");
+
+  describe("functionUnderTest", function () {
+    describe("input validation", function () {
+      it("should throw error when required param missing", function () {
+        expect(() => functionUnderTest()).to.throw();
+      });
+    });
+
+    describe("happy path", function () {
+      it("should return expected result for valid input", function () {
+        const result = functionUnderTest({ validInput: true });
+        expect(result).to.deep.equal(expectedOutput);
+      });
+    });
+
+    describe("edge cases", function () {
+      it("should handle boundary condition", function () {
+        // test edge case
+      });
+    });
+  });
+})();
+```
+
+### 6. Checklist
+
+Before completing any code change:
+
+- [ ] Tests written BEFORE implementation (or for existing code: tests added)
+- [ ] All tests pass (`npm test`)
+- [ ] Coverage hasn't decreased (`npm run test:coverage:ratchet`)
+- [ ] New code has corresponding test coverage
+- [ ] Error paths are tested (not just happy paths)
+
+## Commands Reference
+
+```bash
+# Run all tests
+npm test
+
+# Run tests with coverage report
+npm run test:coverage
+
+# Run coverage ratchet check
+npm run test:coverage:ratchet
+
+# Generate HTML coverage report
+npm run test:coverage:html
+```
+
+## Common Patterns
+
+### Testing async functions
+
+```javascript
+it("should handle async operation", async function () {
+  const result = await asyncFunction();
+  expect(result).to.exist;
+});
+```
+
+### Mocking with Sinon
+
+```javascript
+const stub = sinon.stub(fs, "readFileSync").returns("mock content");
+try {
+  const result = functionUnderTest();
+  expect(result).to.equal("expected");
+} finally {
+  stub.restore();
+}
+```
+
+### Testing error handling
+
+```javascript
+it("should throw on invalid input", function () {
+  expect(() => functionUnderTest(null)).to.throw(/error message/);
+});
+```
+
+### Testing transformations
+
+```javascript
+it("should transform v2 object to v3", function () {
+  const result = transformToSchemaKey({
+    currentSchema: "schema_v2",
+    targetSchema: "schema_v3",
+    object: v2Object,
+  });
+  expect(result.newProperty).to.equal(expectedValue);
+});
+```

.github/workflows/auto-dev-release.yml

@@ -100,6 +100,12 @@ jobs:
         if: steps.check_changes.outputs.skip_release == 'false'
         run: npm run build
 
+      - name: Run coverage and ratchet check
+        if: steps.check_changes.outputs.skip_release == 'false'
+        run: |
+          npm run test:coverage
+          npm run test:coverage:ratchet
+
       - name: Configure Git
         run: |
           git config --global user.name 'github-actions[bot]'

.github/workflows/npm-test.yml

@@ -38,6 +38,28 @@ jobs:
           node-version: ${{ matrix.node }}
       - run: npm ci
       - run: npm run build # Automatically run tests because of the `postbuild` script in package.json
+
+  coverage:
+    name: Coverage Check
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          cache: "npm"
+          cache-dependency-path: package-lock.json
+          node-version: 20
+      - run: npm ci
+      - run: npm run dereferenceSchemas
+      - name: Run tests with coverage
+        run: npm run test:coverage
+      - name: Check coverage ratchet
+        run: npm run test:coverage:ratchet
+      - name: Upload coverage report
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-report
+          path: coverage/
 
   threat-assessment:
     if: github.event_name == 'release' && github.event.action == 'published'

AGENTS.md

@@ -106,6 +106,8 @@ When creating new schema version (e.g., v4):
 **Test structure (Mocha + Chai):**
 - `test/schema.test.js`: Validates all schema examples (auto-generated from schemas)
 - `test/files.test.js`: Unit tests for `readFile()` with Sinon stubs
+- `test/validate.test.js`: Tests for `validate()` and `transformToSchemaKey()`
+- `test/resolvePaths.test.js`: Tests for path resolution
 
 **Run tests:** `npm test` (or `mocha`)
 
@@ -115,6 +117,51 @@ const result = validate({ schemaKey: "step_v3", object: example });
 assert.ok(result.valid, `Validation failed: ${result.errors}`);
 ```
 
+### Testing Requirements (CRITICAL)
+
+**TDD is mandatory for this project.** All code changes must follow test-driven development:
+
+1. **Write tests first** - before any implementation
+2. **Run tests** - verify they fail (red)
+3. **Write implementation** - make tests pass
+4. **Run tests** - verify they pass (green)
+5. **Check coverage** - must not decrease
+
+**Coverage enforcement:**
+
+```bash
+# Run tests with coverage
+npm run test:coverage
+
+# Verify coverage baseline (CI enforces this)
+npm run test:coverage:ratchet
+
+# Generate HTML report for detailed analysis
+npm run test:coverage:html
+```
+
+**Current coverage thresholds (enforced by CI):**
+
+| Metric | Threshold |
+|--------|-----------|
+| Lines | 100% |
+| Statements | 100% |
+| Functions | 100% |
+| Branches | 100% |
+
+**Coverage ratchet:** Thresholds in `coverage-thresholds.json` can only increase. CI fails if coverage decreases.
+
+**Test file mapping:**
+
+| Source | Test File |
+|--------|-----------|
+| `src/validate.js` | `test/validate.test.js` |
+| `src/resolvePaths.js` | `test/resolvePaths.test.js` |
+| `src/files.js` | `test/files.test.js` |
+| Schema examples | `test/schema.test.js` |
+
+**AI Tooling:** See `.claude/skills/tdd-coverage/SKILL.md` for detailed TDD workflow.
+
 ### Version Management & CI/CD Workflows
 
 #### Auto Dev Release (`.github/workflows/auto-dev-release.yml`)

CLAUDE.md

@@ -0,0 +1,38 @@
+# Claude Code Configuration
+
+This file is a pointer for Claude Code and similar AI assistants.
+
+## Primary Documentation
+
+See **[AGENTS.md](./AGENTS.md)** for complete project guidelines, architecture, and development workflows.
+
+## Quick Reference
+
+### Testing (CRITICAL)
+
+**All code changes require TDD:**
+1. Write tests first
+2. Verify tests fail
+3. Write implementation
+4. Verify tests pass
+5. Check coverage: `npm run test:coverage:ratchet`
+
+**Coverage must never decrease.**
+
+### Available Commands
+
+```bash
+npm test                     # Run tests
+npm run test:coverage        # Tests + coverage report
+npm run test:coverage:ratchet # Verify coverage baseline
+npm run build               # Build schemas
+```
+
+### Key Files
+
+| Purpose | Location |
+|---------|----------|
+| Project guidelines | `AGENTS.md` |
+| TDD/Coverage skill | `.claude/skills/tdd-coverage/SKILL.md` |
+| Coverage config | `.c8rc.json` |
+| Coverage baseline | `coverage-thresholds.json` |

coverage-thresholds.json

@@ -0,0 +1,8 @@
+{
+  "description": "Coverage baseline thresholds. These values should only increase, never decrease.",
+  "lastUpdated": "2026-01-07",
+  "lines": 100,
+  "statements": 100,
+  "functions": 100,
+  "branches": 100
+}