test: add IIFE test for REPL

README.md

@@ -452,8 +452,6 @@ For information about the governance of the Node.js project, see
   **Mohammed Keyvanzadeh** <<[email protected]>> (he/him)
 * [watilde](https://github.com/watilde) -
   **Daijiro Wachi** <<[email protected]>> (he/him)
-* [watson](https://github.com/watson) -
-  **Thomas Watson** <<[email protected]>>
 * [XadillaX](https://github.com/XadillaX) -
   **Khaidi Chu** <<[email protected]>> (he/him)
 * [yashLadha](https://github.com/yashLadha) -
@@ -620,6 +618,8 @@ For information about the governance of the Node.js project, see
   **Vladimir Kurchatkin** <<[email protected]>>
 * [vsemozhetbyt](https://github.com/vsemozhetbyt) -
   **Vse Mozhet Byt** <<[email protected]>> (he/him)
+* [watson](https://github.com/watson) -
+  **Thomas Watson** <<[email protected]>>
 * [whitlockjc](https://github.com/whitlockjc) -
   **Jeremy Whitlock** <<[email protected]>>
 * [yhwang](https://github.com/yhwang) -

test/parallel/test-repl-IIFE.js

@@ -0,0 +1,50 @@
+'use strict';
+
+// REPL regression test for IIFE https://github.com/nodejs/node/issues/38685
+
+require('../common');
+const util = require('util');
+const assert = require('assert');
+const ArrayStream = require('../common/arraystream');
+const repl = require('repl');
+
+// Create a dummy stream that does nothing
+const stream = new ArrayStream();
+let output = '';
+
+function testNormalIIFE() {
+  const server = runRepl();
+
+  stream.run(['(() => true)()']);
+  assert.strictEqual(output, '> true\n> ');
+  output = '';
+  server.close();
+  testAsyncIIEF();
+}
+
+function testAsyncIIEF() {
+  const server = runRepl();
+  const asyncFn = '(async() => true)();';
+
+  stream.run([asyncFn]);
+  // promise output twice
+  output = util.inspect(output).split('\\n> ')[1];
+  assert.strictEqual(output, 'Promise { <pending> }');
+  output = '';
+  server.close();
+}
+
+// run repl
+function runRepl() {
+  stream.write = function(d) {
+    output += d;
+  };
+
+  return repl.start({
+    input: stream,
+    output: stream
+  });
+}
+
+// start
+testNormalIIFE();