From e3055dc5254502d2f02276f20c9a3f37b41e7f12 Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Fri, 25 Jan 2019 08:26:53 +0100
Subject: [PATCH] repl: simplify and improve completion
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The completion lists used a hand crafted list of global entries that
was redundant due to also using the actual global properties for tab
completion. Those entries ended up in an separated completion group
which did not seem useful.

PR-URL: https://github.com/nodejs/node/pull/25731
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
---
 lib/repl.js                             | 58 ++++++++-----------------
 test/parallel/test-repl-tab-complete.js |  2 +-
 2 files changed, 18 insertions(+), 42 deletions(-)

diff --git a/lib/repl.js b/lib/repl.js
index 30812c232b7639..df861843d1d501 100644
--- a/lib/repl.js
+++ b/lib/repl.js
@@ -89,18 +89,6 @@ let processTopLevelAwait;
 const parentModule = module;
 const replMap = new WeakMap();
 
-const GLOBAL_OBJECT_PROPERTIES = [
-  'NaN', 'Infinity', 'undefined', 'eval', 'parseInt', 'parseFloat', 'isNaN',
-  'isFinite', 'decodeURI', 'decodeURIComponent', 'encodeURI',
-  'encodeURIComponent', 'Object', 'Function', 'Array', 'String', 'Boolean',
-  'Number', 'Date', 'RegExp', 'Error', 'EvalError', 'RangeError',
-  'ReferenceError', 'SyntaxError', 'TypeError', 'URIError', 'Math', 'JSON'
-];
-const GLOBAL_OBJECT_PROPERTY_MAP = {};
-for (var n = 0; n < GLOBAL_OBJECT_PROPERTIES.length; n++) {
-  GLOBAL_OBJECT_PROPERTY_MAP[GLOBAL_OBJECT_PROPERTIES[n]] =
-    GLOBAL_OBJECT_PROPERTIES[n];
-}
 const kBufferedCommandSymbol = Symbol('bufferedCommand');
 const kContextId = Symbol('contextId');
 
@@ -807,6 +795,10 @@ REPLServer.prototype.createContext = function() {
     }, () => {
       context = vm.createContext();
     });
+    for (const name of Object.getOwnPropertyNames(global)) {
+      Object.defineProperty(context, name,
+                            Object.getOwnPropertyDescriptor(global, name));
+    }
     context.global = context;
     const _console = new Console(this.outputStream);
     Object.defineProperty(context, 'console', {
@@ -814,17 +806,6 @@ REPLServer.prototype.createContext = function() {
       writable: true,
       value: _console
     });
-
-    var names = Object.getOwnPropertyNames(global);
-    for (var n = 0; n < names.length; n++) {
-      var name = names[n];
-      if (name === 'console' || name === 'global')
-        continue;
-      if (GLOBAL_OBJECT_PROPERTY_MAP[name] === undefined) {
-        Object.defineProperty(context, name,
-                              Object.getOwnPropertyDescriptor(global, name));
-      }
-    }
   }
 
   var module = new CJSModule('<repl>');
@@ -1137,19 +1118,19 @@ function complete(line, callback) {
           }
           completionGroups.push(
             filteredOwnPropertyNames.call(this, this.context));
-          addStandardGlobals(completionGroups, filter);
+          if (filter !== '') addCommonWords(completionGroups);
           completionGroupsLoaded();
         } else {
           this.eval('.scope', this.context, 'repl', function ev(err, globals) {
             if (err || !Array.isArray(globals)) {
-              addStandardGlobals(completionGroups, filter);
+              if (filter !== '') addCommonWords(completionGroups);
             } else if (Array.isArray(globals[0])) {
               // Add grouped globals
               for (var n = 0; n < globals.length; n++)
                 completionGroups.push(globals[n]);
             } else {
               completionGroups.push(globals);
-              addStandardGlobals(completionGroups, filter);
+              if (filter !== '') addCommonWords(completionGroups);
             }
             completionGroupsLoaded();
           });
@@ -1373,21 +1354,16 @@ function _memory(cmd) {
   }
 }
 
-function addStandardGlobals(completionGroups, filter) {
-  // Global object properties
-  // (http://www.ecma-international.org/publications/standards/Ecma-262.htm)
-  completionGroups.push(GLOBAL_OBJECT_PROPERTIES);
-  // Common keywords. Exclude for completion on the empty string, b/c
-  // they just get in the way.
-  if (filter) {
-    completionGroups.push([
-      'async', 'await', 'break', 'case', 'catch', 'const', 'continue',
-      'debugger', 'default', 'delete', 'do', 'else', 'export', 'false',
-      'finally', 'for', 'function', 'if', 'import', 'in', 'instanceof', 'let',
-      'new', 'null', 'return', 'switch', 'this', 'throw', 'true', 'try',
-      'typeof', 'undefined', 'var', 'void', 'while', 'with', 'yield'
-    ]);
-  }
+function addCommonWords(completionGroups) {
+  // Only words which do not yet exist as global property should be added to
+  // this list.
+  completionGroups.push([
+    'async', 'await', 'break', 'case', 'catch', 'const', 'continue',
+    'debugger', 'default', 'delete', 'do', 'else', 'export', 'false',
+    'finally', 'for', 'function', 'if', 'import', 'in', 'instanceof', 'let',
+    'new', 'null', 'return', 'switch', 'this', 'throw', 'true', 'try',
+    'typeof', 'var', 'void', 'while', 'with', 'yield'
+  ]);
 }
 
 function _turnOnEditorMode(repl) {
diff --git a/test/parallel/test-repl-tab-complete.js b/test/parallel/test-repl-tab-complete.js
index 4c68ec2c8f383b..5438c960b84cb1 100644
--- a/test/parallel/test-repl-tab-complete.js
+++ b/test/parallel/test-repl-tab-complete.js
@@ -457,7 +457,7 @@ const testNonGlobal = repl.start({
   useGlobal: false
 });
 
-const builtins = [['Infinity', '', 'Int16Array', 'Int32Array',
+const builtins = [['Infinity', 'Int16Array', 'Int32Array',
                    'Int8Array'], 'I'];
 
 if (common.hasIntl) {