repl: do not include legacy getter/setter methods in completion

For every object that inherits from `Object.prototype`, the REPL
includes the `Object.prototype` methods in its autocompletion.
This is already a little noisy, but in particular, this also
includes the legacy `__defineGetter__` family of methods;
since those are deprecated and not in practical use anymore,
it helps reduce noise a bit to remove them.
This commit does not remove `__proto__` as it is a little
more popular and, despite its downsides, a slightly more convenient
way to access the prototype of an object in the REPL than
`Object.getPrototypeOf(...)`.
PR-URL: #39576
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

Author: addaleax

lib/repl.js

@@ -1188,11 +1188,31 @@ function isIdentifier(str) {
 returntrue;
 }
 
+functionisNotLegacyObjectPrototypeMethod(str){
+returnisIdentifier(str)&&
+str!=='__defineGetter__'&&
+str!=='__defineSetter__'&&
+str!=='__lookupGetter__'&&
+str!=='__lookupSetter__';
+}
+
 functionfilteredOwnPropertyNames(obj){
 if(!obj)return[];
+// `Object.prototype` is the only non-contrived object that fulfills
+// `Object.getPrototypeOf(X) === null &&
+// Object.getPrototypeOf(Object.getPrototypeOf(X.constructor)) === X`.
+letisObjectPrototype=false;
+if(ObjectGetPrototypeOf(obj)===null){
+constctorDescriptor=ObjectGetOwnPropertyDescriptor(obj,'constructor');
+if(ctorDescriptor&&ctorDescriptor.value){
+constctorProto=ObjectGetPrototypeOf(ctorDescriptor.value);
+isObjectPrototype=ctorProto&&ObjectGetPrototypeOf(ctorProto)===obj;
+}
+}
 constfilter=ALL_PROPERTIES|SKIP_SYMBOLS;
-returnArrayPrototypeFilter(getOwnNonIndexProperties(obj,filter),
-isIdentifier);
+returnArrayPrototypeFilter(
+getOwnNonIndexProperties(obj,filter),
+isObjectPrototype ? isNotLegacyObjectPrototypeMethod : isIdentifier);
 }
 
 functiongetGlobalLexicalScopeNames(contextId){

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

@@ -443,6 +443,18 @@ testMe.complete('obj.', common.mustCall((error, data) => {
 assert(data[0].includes('obj.key'));
 }));
 
+// Make sure tab completion does not include __defineSetter__ and friends.
+putIn.run(['.clear']);
+
+putIn.run(['var obj = {};']);
+testMe.complete('obj.',common.mustCall(function(error,data){
+assert.strictEqual(data[0].includes('obj.__defineGetter__'),false);
+assert.strictEqual(data[0].includes('obj.__defineSetter__'),false);
+assert.strictEqual(data[0].includes('obj.__lookupGetter__'),false);
+assert.strictEqual(data[0].includes('obj.__lookupSetter__'),false);
+assert.strictEqual(data[0].includes('obj.__proto__'),true);
+}));
+
 // Tab completion for files/directories
 {
 putIn.run(['.clear']);