diff --git a/lib/util.js b/lib/util.js index 136a66a6c1c0e8..c5d7bea7db352d 100644 --- a/lib/util.js +++ b/lib/util.js @@ -167,6 +167,22 @@ function arrayToHash(array) { } +function getConstructorOf(obj) { + while (obj) { + var descriptor = Object.getOwnPropertyDescriptor(obj, 'constructor'); + if (descriptor !== undefined && + typeof descriptor.value === 'function' && + descriptor.value.name !== '') { + return descriptor.value; + } + + obj = Object.getPrototypeOf(obj); + } + + return null; +} + + function inspectPromise(p) { Debug = Debug || require('vm').runInDebugContext('Debug'); var mirror = Debug.MakeMirror(p, true); @@ -260,14 +276,17 @@ function formatValue(ctx, value, recurseTimes) { } } + var constructor = getConstructorOf(value); var base = '', empty = false, braces, formatter; if (Array.isArray(value)) { + if (constructor === Array) + constructor = null; braces = ['[', ']']; empty = value.length === 0; formatter = formatArray; } else if (value instanceof Set) { - braces = ['Set {', '}']; + braces = ['{', '}']; // With `showHidden`, `length` will display as a hidden property for // arrays. For consistency's sake, do the same for `size`, even though this // property isn't selected by Object.getOwnPropertyNames(). @@ -276,7 +295,7 @@ function formatValue(ctx, value, recurseTimes) { empty = value.size === 0; formatter = formatSet; } else if (value instanceof Map) { - braces = ['Map {', '}']; + braces = ['{', '}']; // Ditto. if (ctx.showHidden) keys.unshift('size'); @@ -286,9 +305,11 @@ function formatValue(ctx, value, recurseTimes) { // Only create a mirror if the object superficially looks like a Promise. var promiseInternals = value instanceof Promise && inspectPromise(value); if (promiseInternals) { - braces = ['Promise {', '}']; + braces = ['{', '}']; formatter = formatPromise; } else { + if (constructor === Object) + constructor = null; braces = ['{', '}']; empty = true; // No other data than keys. formatter = formatObject; @@ -336,6 +357,10 @@ function formatValue(ctx, value, recurseTimes) { base = ' ' + '[Boolean: ' + formatted + ']'; } + // Add constructor name if available + if (base === '' && constructor) + braces[0] = constructor.name + ' ' + braces[0]; + if (empty === true) { return braces[0] + base + braces[1]; } diff --git a/test/parallel/test-sys.js b/test/parallel/test-sys.js index bbc8c092002af6..9367e55c687f2f 100644 --- a/test/parallel/test-sys.js +++ b/test/parallel/test-sys.js @@ -17,7 +17,7 @@ assert.equal(new Date('2010-02-14T12:48:40+01:00').toString(), assert.equal("'\\n\\u0001'", common.inspect('\n\u0001')); assert.equal('[]', common.inspect([])); -assert.equal('{}', common.inspect(Object.create([]))); +assert.equal('Array {}', common.inspect(Object.create([]))); assert.equal('[ 1, 2 ]', common.inspect([1, 2])); assert.equal('[ 1, [ 2, 3 ] ]', common.inspect([1, [2, 3]])); diff --git a/test/parallel/test-util-inspect.js b/test/parallel/test-util-inspect.js index f583005ce96f75..fcde1c74c3984e 100644 --- a/test/parallel/test-util-inspect.js +++ b/test/parallel/test-util-inspect.js @@ -61,7 +61,7 @@ assert.ok(ex.indexOf('[message]') != -1); // GH-1941 // should not throw: -assert.equal(util.inspect(Object.create(Date.prototype)), '{}'); +assert.equal(util.inspect(Object.create(Date.prototype)), 'Date {}'); // GH-1944 assert.doesNotThrow(function() { @@ -306,3 +306,44 @@ checkAlignment(function() { }()); checkAlignment(new Set(big_array)); checkAlignment(new Map(big_array.map(function(y) { return [y, null]; }))); + + +// Test display of constructors + +class ObjectSubclass {} +class ArraySubclass extends Array {} +class SetSubclass extends Set {} +class MapSubclass extends Map {} +class PromiseSubclass extends Promise {} + +var x = new ObjectSubclass(); +x.foo = 42; +assert.equal(util.inspect(x), + 'ObjectSubclass { foo: 42 }'); +assert.equal(util.inspect(new ArraySubclass(1, 2, 3)), + 'ArraySubclass [ 1, 2, 3 ]'); +assert.equal(util.inspect(new SetSubclass([1, 2, 3])), + 'SetSubclass { 1, 2, 3 }'); +assert.equal(util.inspect(new MapSubclass([['foo', 42]])), + 'MapSubclass { \'foo\' => 42 }'); +assert.equal(util.inspect(new PromiseSubclass(function() {})), + 'PromiseSubclass { }'); + +// Corner cases. +var x = { constructor: 42 }; +assert.equal(util.inspect(x), '{ constructor: 42 }'); + +var x = {}; +Object.defineProperty(x, 'constructor', { + get: function() { + throw new Error('should not access constructor'); + }, + enumerable: true +}); +assert.equal(util.inspect(x), '{ constructor: [Getter] }'); + +var x = new (function() {}); +assert.equal(util.inspect(x), '{}'); + +var x = Object.create(null); +assert.equal(util.inspect(x), '{}');