test(skills): add unit and CLI tests for the sync CLI

Guard the CLI entrypoint so the module is importable, export the pure helpers, and add node:test suites (no new deps) covering repo inference, .skills.local parsing, frontmatter, maturity/domain filtering, arg parsing, skill collection, and CLI commands. Wire `test` to `node --test`.

Author: abretonc7s

bin/metamask-skills.mjs

@@ -3,7 +3,7 @@ import { spawnSync } from 'node:child_process';
 import { mkdirSync, readdirSync, readFileSync, statSync } from 'node:fs';
 import os from 'node:os';
 import path from 'node:path';
-import { fileURLToPath } from 'node:url';
+import { fileURLToPath, pathToFileURL } from 'node:url';
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url));
 const PACKAGE_ROOT = path.resolve(__dirname, '..');
@@ -737,31 +737,61 @@ function postinstall(args) {
   }
 }
 
-const [command, ...args] = process.argv.slice(2);
-if (!command || command === '-h' || command === '--help') {
-  usage(0);
-}
-
-let exitCode;
-try {
-  if (command === 'list') {
-    exitCode = listSkills(args);
-  } else if (command === 'search') {
-    exitCode = searchSkills(args);
-  } else if (command === 'describe') {
-    exitCode = describeSkill(args);
-  } else if (command === 'sync') {
-    exitCode = sync(args);
-  } else if (command === 'postinstall') {
-    exitCode = postinstall(args);
-  } else if (command === 'install') {
-    exitCode = install(args);
-  } else {
-    process.stderr.write(`Unknown command: ${command}\n\n`);
-    usage(1);
+export {
+  bodyAfterFrontmatter,
+  collectSkills,
+  domainMatches,
+  expandHome,
+  filterSkills,
+  findSkill,
+  formatSkillTable,
+  getConfigValue,
+  hasArg,
+  isTruthy,
+  maturityMatches,
+  parseDiscoveryArgs,
+  parseFrontmatter,
+  parseGlobalArgs,
+  parseSkillsLocal,
+  repoNameFromGitHubUrl,
+  repoOverlays,
+  hasSkillsSource,
+  shouldSkipPostinstall,
+  splitList,
+  stripInlineComment,
+  unquote,
+};
+
+const invokedDirectly =
+  Boolean(process.argv[1]) && import.meta.url === pathToFileURL(process.argv[1]).href;
+
+if (invokedDirectly) {
+  const [command, ...args] = process.argv.slice(2);
+  if (!command || command === '-h' || command === '--help') {
+    usage(0);
+  }
+
+  let exitCode;
+  try {
+    if (command === 'list') {
+      exitCode = listSkills(args);
+    } else if (command === 'search') {
+      exitCode = searchSkills(args);
+    } else if (command === 'describe') {
+      exitCode = describeSkill(args);
+    } else if (command === 'sync') {
+      exitCode = sync(args);
+    } else if (command === 'postinstall') {
+      exitCode = postinstall(args);
+    } else if (command === 'install') {
+      exitCode = install(args);
+    } else {
+      process.stderr.write(`Unknown command: ${command}\n\n`);
+      usage(1);
+    }
+  } catch (error) {
+    process.stderr.write(`metamask-skills: ${error instanceof Error ? error.message : String(error)}\n`);
+    exitCode = 1;
   }
-} catch (error) {
-  process.stderr.write(`metamask-skills: ${error instanceof Error ? error.message : String(error)}\n`);
-  exitCode = 1;
+  process.exit(exitCode);
 }
-process.exit(exitCode);

package.json

@@ -18,7 +18,7 @@
   "scripts": {
     "smoke": "node bin/metamask-skills.mjs --help",
     "build": "node bin/metamask-skills.mjs --help",
-    "test": "node bin/metamask-skills.mjs --help",
+    "test": "node --test test/*.test.mjs",
     "pack:dry-run": "npm pack --dry-run",
     "changelog:validate": "bash scripts/validate-changelog.sh",
     "create-release-branch": "create-release-branch --formatter oxfmt"

test/cli.test.mjs

@@ -0,0 +1,81 @@
+import assert from 'node:assert/strict';
+import { spawnSync } from 'node:child_process';
+import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import os from 'node:os';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { after, before, describe, test } from 'node:test';
+
+const BIN = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..', 'bin', 'metamask-skills.mjs');
+
+function runCli(args, env = {}) {
+  return spawnSync(process.execPath, [BIN, ...args], {
+    encoding: 'utf8',
+    maxBuffer: 16 * 1024 * 1024,
+    // Neutralize any source-dir env vars from the host shell so tests are deterministic.
+    env: { ...process.env, METAMASK_SKILLS_DIR: '', CONSENSYS_SKILLS_DIR: '', ...env },
+  });
+}
+
+describe('CLI entrypoint', () => {
+  test('--help prints usage and exits 0', () => {
+    const result = runCli(['--help']);
+    assert.equal(result.status, 0);
+    assert.match(result.stdout, /MetaMask skills CLI/u);
+    assert.match(result.stdout, /metamask-skills sync/u);
+  });
+
+  test('no command prints usage and exits 0', () => {
+    const result = runCli([]);
+    assert.equal(result.status, 0);
+    assert.match(result.stdout, /Usage:/u);
+  });
+
+  test('unknown command exits 1 with error', () => {
+    const result = runCli(['frobnicate']);
+    assert.equal(result.status, 1);
+    assert.match(result.stderr, /Unknown command: frobnicate/u);
+  });
+});
+
+describe('CLI list against a fixture source', () => {
+  let root;
+  let source;
+
+  before(() => {
+    root = mkdtempSync(path.join(os.tmpdir(), 'mms-cli-'));
+    source = path.join(root, 'skills-source');
+    const skillDir = path.join(source, 'domains', 'testing', 'skills', 'unit-testing');
+    mkdirSync(path.join(skillDir, 'repos'), { recursive: true });
+    mkdirSync(path.join(source, 'tools'), { recursive: true });
+    writeFileSync(
+      path.join(skillDir, 'skill.md'),
+      ['---', 'name: unit-testing', 'description: Write unit tests', 'maturity: stable', '---', 'Body.'].join('\n'),
+    );
+  });
+
+  after(() => {
+    rmSync(root, { recursive: true, force: true });
+  });
+
+  test('list --json emits valid JSON scoped to the configured source', () => {
+    const result = runCli(['list', '--json', '--target', root, '--repo', 'core'], {
+      METAMASK_SKILLS_DIR: source,
+    });
+    assert.equal(result.status, 0);
+    const parsed = JSON.parse(result.stdout);
+    assert.equal(parsed.repo, 'core');
+    assert.deepEqual(parsed.sources, [source]);
+    assert.deepEqual(parsed.skills.map((s) => s.id), ['testing/unit-testing']);
+  });
+
+  test('search narrows results and exits 0', () => {
+    const result = runCli(['search', 'unit', '--json', '--target', root], {
+      METAMASK_SKILLS_DIR: source,
+    });
+    assert.equal(result.status, 0);
+    const parsed = JSON.parse(result.stdout);
+    assert.equal(parsed.skills.length, 1);
+    assert.equal(parsed.query, 'unit');
+  });
+});