test: add install_to_bmad design contract tests

Unit tests against getInstallToBmad and loadSkillManifest that nail
down the 4 core design decisions for the install_to_bmad flag.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

test/test-install-to-bmad.js

@@ -0,0 +1,154 @@
+/**
+ * install_to_bmad Flag — Design Contract Tests
+ *
+ * Unit tests against the functions that implement the install_to_bmad flag.
+ * These nail down the 4 core design decisions:
+ *
+ * 1. true/omitted → skill stays in _bmad/ (default behavior)
+ * 2. false → skill removed from _bmad/ after IDE install
+ * 3. No platform → no cleanup runs (cleanup lives in installVerbatimSkills)
+ * 4. Mixed flags → each skill evaluated independently
+ *
+ * Usage: node test/test-install-to-bmad.js
+ */
+
+const path = require('node:path');
+const os = require('node:os');
+const fs = require('fs-extra');
+const { loadSkillManifest, getInstallToBmad } = require('../tools/cli/installers/lib/ide/shared/skill-manifest');
+
+// ANSI colors
+const colors = {
+  reset: '\u001B[0m',
+  green: '\u001B[32m',
+  red: '\u001B[31m',
+  yellow: '\u001B[33m',
+  cyan: '\u001B[36m',
+  dim: '\u001B[2m',
+};
+
+let passed = 0;
+let failed = 0;
+
+function assert(condition, testName, errorMessage = '') {
+  if (condition) {
+    console.log(`${colors.green}✓${colors.reset} ${testName}`);
+    passed++;
+  } else {
+    console.log(`${colors.red}✗${colors.reset} ${testName}`);
+    if (errorMessage) {
+      console.log(`  ${colors.dim}${errorMessage}${colors.reset}`);
+    }
+    failed++;
+  }
+}
+
+async function runTests() {
+  console.log(`${colors.cyan}========================================`);
+  console.log('install_to_bmad — Design Contract Tests');
+  console.log(`========================================${colors.reset}\n`);
+
+  // ============================================================
+  // 1. true/omitted → getInstallToBmad returns true (keep in _bmad/)
+  // ============================================================
+  console.log(`${colors.yellow}Design decision 1: true or omitted → skill stays in _bmad/${colors.reset}\n`);
+
+  // Null manifest (no bmad-skill-manifest.yaml) → true
+  assert(getInstallToBmad(null, 'workflow.md') === true, 'null manifest defaults to true');
+
+  // Single-entry, flag omitted → true
+  assert(
+    getInstallToBmad({ __single: { type: 'skill' } }, 'workflow.md') === true,
+    'single-entry manifest with flag omitted defaults to true',
+  );
+
+  // Single-entry, explicit true → true
+  assert(
+    getInstallToBmad({ __single: { type: 'skill', install_to_bmad: true } }, 'workflow.md') === true,
+    'single-entry manifest with explicit true returns true',
+  );
+
+  console.log('');
+
+  // ============================================================
+  // 2. false → getInstallToBmad returns false (remove from _bmad/)
+  // ============================================================
+  console.log(`${colors.yellow}Design decision 2: false → skill removed from _bmad/${colors.reset}\n`);
+
+  // Single-entry, explicit false → false
+  assert(
+    getInstallToBmad({ __single: { type: 'skill', install_to_bmad: false } }, 'workflow.md') === false,
+    'single-entry manifest with explicit false returns false',
+  );
+
+  // loadSkillManifest round-trip: YAML with false is preserved through load
+  {
+    const tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), 'bmad-itb-'));
+    await fs.writeFile(path.join(tmpDir, 'bmad-skill-manifest.yaml'), 'type: skill\ninstall_to_bmad: false\n');
+    const loaded = await loadSkillManifest(tmpDir);
+    assert(getInstallToBmad(loaded, 'workflow.md') === false, 'loadSkillManifest preserves install_to_bmad: false through round-trip');
+    await fs.remove(tmpDir);
+  }
+
+  console.log('');
+
+  // ============================================================
+  // 3. No platform → cleanup only runs inside installVerbatimSkills
+  //    (This is a design invariant: getInstallToBmad is only consulted
+  //     during IDE install. Without a platform, the flag has no effect.)
+  // ============================================================
+  console.log(`${colors.yellow}Design decision 3: flag is a per-skill property, not a pipeline gate${colors.reset}\n`);
+
+  // The flag value is stored but doesn't trigger any side effects by itself.
+  // Cleanup is driven by reading the CSV column inside installVerbatimSkills.
+  // We verify the flag is just data — getInstallToBmad doesn't touch the filesystem.
+  {
+    const manifest = { __single: { type: 'skill', install_to_bmad: false } };
+    const result = getInstallToBmad(manifest, 'workflow.md');
+    assert(typeof result === 'boolean', 'getInstallToBmad returns a boolean (pure data, no side effects)');
+    assert(result === false, 'false value is faithfully returned for consumer to act on');
+  }
+
+  console.log('');
+
+  // ============================================================
+  // 4. Mixed flags → each skill evaluated independently
+  // ============================================================
+  console.log(`${colors.yellow}Design decision 4: mixed flags — each skill independent${colors.reset}\n`);
+
+  // Multi-entry manifest: different files can have different flags
+  {
+    const manifest = {
+      'workflow.md': { type: 'skill', install_to_bmad: false },
+      'other.md': { type: 'skill', install_to_bmad: true },
+    };
+    assert(getInstallToBmad(manifest, 'workflow.md') === false, 'multi-entry: workflow.md with false returns false');
+    assert(getInstallToBmad(manifest, 'other.md') === true, 'multi-entry: other.md with true returns true');
+    assert(getInstallToBmad(manifest, 'unknown.md') === true, 'multi-entry: unknown file defaults to true');
+  }
+
+  console.log('');
+
+  // ============================================================
+  // Summary
+  // ============================================================
+  console.log(`${colors.cyan}========================================`);
+  console.log('Results:');
+  console.log(`  Passed: ${colors.green}${passed}${colors.reset}`);
+  console.log(`  Failed: ${colors.red}${failed}${colors.reset}`);
+  console.log(`========================================${colors.reset}\n`);
+
+  if (failed === 0) {
+    console.log(`${colors.green}All install_to_bmad contract tests passed!${colors.reset}\n`);
+    process.exit(0);
+  } else {
+    console.log(`${colors.red}Some install_to_bmad contract tests failed${colors.reset}\n`);
+    process.exit(1);
+  }
+}
+
+runTests().catch((error) => {
+  console.error(`${colors.red}Test runner failed:${colors.reset}`, error.message);
+  console.error(error.stack);
+  process.exit(1);
+});