fix(scripts): add help to coverage gates (#3070)

Co-authored-by: Steven Enamakel <enamakel@tinyhumans.ai>

scripts/__tests__/coverage-script-help.test.mjs

@@ -0,0 +1,41 @@
+import assert from 'node:assert/strict';
+import { spawnSync } from 'node:child_process';
+import { dirname, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { test } from 'node:test';
+
+const HERE = dirname(fileURLToPath(import.meta.url));
+const SCRIPTS = resolve(HERE, '..');
+
+function run(scriptName, args) {
+  return spawnSync(process.execPath, [resolve(SCRIPTS, scriptName), ...args], {
+    encoding: 'utf8',
+  });
+}
+
+test('coverage helper scripts print help without running checks', () => {
+  for (const [scriptName, usage] of [
+    ['check-coverage-matrix.mjs', 'Usage: node scripts/check-coverage-matrix.mjs'],
+    ['check-domain-e2e-coverage.mjs', 'Usage: node scripts/check-domain-e2e-coverage.mjs'],
+  ]) {
+    for (const helpFlag of ['--help', '-h']) {
+      const result = run(scriptName, [helpFlag]);
+
+      assert.equal(result.status, 0, result.stderr);
+      assert.equal(result.stdout.trim(), usage);
+      assert.equal(result.stderr, '');
+    }
+  }
+});
+
+test('coverage helper scripts reject unknown arguments', () => {
+  for (const [scriptName, error] of [
+    ['check-coverage-matrix.mjs', /check-coverage-matrix: unknown argument: --bogus/],
+    ['check-domain-e2e-coverage.mjs', /check-domain-e2e-coverage: unknown argument: --bogus/],
+  ]) {
+    const result = run(scriptName, ['--bogus']);
+
+    assert.equal(result.status, 2, result.stdout);
+    assert.match(result.stderr, error);
+  }
+});

scripts/check-coverage-matrix.mjs

@@ -7,6 +7,20 @@ import { parseMatrix, validateAgainstCatalog } from './lib/coverage-matrix-parse
 const here = dirname(fileURLToPath(import.meta.url));
 const repoRoot = join(here, '..');
 
+function usage() {
+  return 'Usage: node scripts/check-coverage-matrix.mjs';
+}
+
+for (const arg of process.argv.slice(2)) {
+  if (arg === '--help' || arg === '-h') {
+    console.log(usage());
+    process.exit(0);
+  }
+  console.error(`check-coverage-matrix: unknown argument: ${arg}`);
+  console.error(usage());
+  process.exit(2);
+}
+
 let matrixMd;
 let catalog;
 try {

scripts/check-domain-e2e-coverage.mjs

@@ -3,6 +3,21 @@ import fs from 'node:fs';
 import path from 'node:path';
 
 const ROOT = process.cwd();
+
+function usage() {
+  return 'Usage: node scripts/check-domain-e2e-coverage.mjs';
+}
+
+for (const arg of process.argv.slice(2)) {
+  if (arg === '--help' || arg === '-h') {
+    console.log(usage());
+    process.exit(0);
+  }
+  console.error(`check-domain-e2e-coverage: unknown argument: ${arg}`);
+  console.error(usage());
+  process.exit(2);
+}
+
 const rawThreshold = process.env.DOMAIN_E2E_COVERAGE_THRESHOLD ?? '90';
 const THRESHOLD = Number(rawThreshold);
 if (!Number.isFinite(THRESHOLD) || THRESHOLD < 0 || THRESHOLD > 100) {