feat: add --expose-gc flag (#4)

README.md

@@ -91,6 +91,7 @@ Note the use of `incremental: true`, which speed up compilation massively.
 * `--timeout` or `-t`, timeouts the tests after a given time; default is 30000 ms
 * `--coverage-exclude` or `-X`, a list of comma-separated patterns to exclude from the coverage report. All tests files are ignored by default.
 * `--ignore` or `-i`, ignore a glob pattern, and not look for tests there
+* `--expose-gc`, exposes the gc() function to tests
 * `--pattern` or `-p`, run tests matching the given glob pattern
 
 ## License

borp.js

@@ -9,6 +9,7 @@ import posix from 'node:path/posix'
 import runWithTypeScript from './lib/run.js'
 import { Report } from 'c8'
 import os from 'node:os'
+import { execa } from 'execa'
 
 let reporter
 /* c8 ignore next 4 */
@@ -30,17 +31,32 @@ const args = parseArgs({
     timeout: { type: 'string', short: 't', default: '30000' },
     'coverage-exclude': { type: 'string', short: 'X', multiple: true },
     ignore: { type: 'string', short: 'i', multiple: true },
+    'expose-gc': { type: 'boolean' },
     help: { type: 'boolean', short: 'h' }
   },
   allowPositionals: true
 })
 
-/* c8 ignore next 4 */
+/* c8 ignore next 5 */
 if (args.values.help) {
   console.log(await readFile(new URL('./README.md', import.meta.url), 'utf8'))
   process.exit(0)
 }
 
+if (args.values['expose-gc'] && typeof global.gc !== 'function') {
+  try {
+    await execa('node', ['--expose-gc', ...process.argv.slice(1)], {
+      stdio: 'inherit',
+      env: {
+        ...process.env
+      }
+    })
+    process.exit(0)
+  } catch (error) {
+    process.exit(1)
+  }
+}
+
 if (args.values.concurrency) {
   args.values.concurrency = parseInt(args.values.concurrency)
 }

fixtures/gc/gc.test.js

@@ -0,0 +1,8 @@
+import { doesNotThrow } from 'node:assert'
+import { test } from 'node:test'
+
+test('this needs gc', () => {
+  doesNotThrow(() => {
+    global.gc()
+  })
+})

test/cli.test.js

@@ -23,3 +23,22 @@ test('failing test set correct status code', async () => {
     cwd: join(import.meta.url, '..', 'fixtures', 'fails')
   }))
 })
+
+test('--expose-gc flag enables garbage collection in tests', async () => {
+  await execa('node', [
+    borp,
+    '--expose-gc'
+  ], {
+    cwd: join(import.meta.url, '..', 'fixtures', 'gc')
+  })
+})
+
+test('failing test with --expose-gc flag sets correct status code', async () => {
+  // execa rejects if status code is not 0
+  await rejects(execa('node', [
+    borp,
+    '--expose-gc'
+  ], {
+    cwd: join(import.meta.url, '..', 'fixtures', 'fails')
+  }))
+})