From e66cb58a9bea0559796f934ff997387503a7d717 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 9f14e5c1c69d3c..4ba6141f59fa5d 100644
--- a/lib/repl.js
+++ b/lib/repl.js
@@ -90,18 +90,6 @@ 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');
 
@@ -806,6 +794,10 @@ 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', {
@@ -813,17 +805,6 @@ 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>');
@@ -1135,19 +1116,19 @@ 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();
           });
@@ -1371,21 +1352,16 @@ 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 69011e4af894f2..0325678ff2e200 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) {