repl: allow autocompletion for scoped packages

Previously, autocompletion of scoped packages was not supported by the
repl due to not including the `@` character in the regular expression.

PR-URL: https://github.com/nodejs/node/pull/10296
Reviewed-By: Prince John Wesley <princejohnwesley@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/repl.js

@@ -787,7 +787,7 @@ ArrayStream.prototype.writable = true;
 ArrayStream.prototype.resume = function() {};
 ArrayStream.prototype.write = function() {};
 
-const requireRE = /\brequire\s*\(['"](([\w./-]+\/)?([\w./-]*))/;
+const requireRE = /\brequire\s*\(['"](([\w@./-]+\/)?([\w@./-]*))/;
 const simpleExpressionRE =
     /(([a-zA-Z_$](?:\w|\$)*)\.)*([a-zA-Z_$](?:\w|\$)*)\.?$/;
 

test/fixtures/node_modules/@nodejsscope/index.js

@@ -0,0 +1 @@
+// Not used

test/parallel/test-repl-tab-complete.js

@@ -1,8 +1,14 @@
 'use strict';
 
-var common = require('../common');
-var assert = require('assert');
-var repl = require('repl');
+const common = require('../common');
+const assert = require('assert');
+
+// We have to change the directory to ../fixtures before requiring repl
+// in order to make the tests for completion of node_modules work properly
+// since repl modifies module.paths.
+process.chdir(common.fixturesDir);
+
+const repl = require('repl');
 
 function getNoResultsFunction() {
   return common.mustCall((err, data) => {
@@ -196,6 +202,15 @@ testMe.complete('require(\'n', common.mustCall(function(error, data) {
   });
 }));
 
+{
+  const expected = ['@nodejsscope', '@nodejsscope/'];
+  putIn.run(['.clear']);
+  testMe.complete('require(\'@nodejs', common.mustCall((err, data) => {
+    assert.strictEqual(err, null);
+    assert.deepStrictEqual(data, [expected, '@nodejs']);
+  }));
+}
+
 // Make sure tab completion works on context properties
 putIn.run(['.clear']);