Recommended coding standards
The following are the coding standards that the Cocos Creator development team use. They are included in the manual for game developers and tool developers reference.
Naming standards
When we name the variables, functions and living examples, we use camelCase nomenclature
// bad var FOOBar = {}; var foo_bar = {}; function FOOBar () {} // good var fooBar = {}; function fooBar () {}
When we name types or modules, we use PascalCase nomenclature
// bad var foobar = cc.Class({ foo: 'foo', bar: 'bar', }); var foobar = require('foo-bar'); // good var FooBar = cc.Class({ foo: 'foo', bar: 'bar', }); var FooBar = require('foo-bar');
Use underscores
_
when naming private attributes// bad this.__firstName__ = 'foobar'; this.firstName_ = 'foobar'; // good this._firstName = 'foobar';
We use dash nomenclature for files
// bad fooBar.js FooBar.js // good foo-bar.js
Grammar standards
Use
Object.create(null)
to create an object// bad var obj = new Object(); // bad var obj = {}; // good var obj = Object.create(null);
Use
[]
to create an array// bad var array = new Array(); // good var array = [];
Try your best to use single quotation marks
''
to define a string in js code// bad var str = "Hello World"; // good var str = 'Hello World';
When defining multi-lines string, try your best to use
+
// bad const errorMessage = 'This is a super long error that was thrown out because of Batman. When you stop to think about how Batman had anything to do with this, you would get nowhere fast.'; // bad const errorMessage = 'This is a super long error that was thrown out because \ of Batman. When you stop to think about how Batman had anything to do \ with this, you would get nowhere \ fast.'; // good const errorMessage = 'This is a super long error that was thrown out because ' + 'of Batman. When you stop to think about how Batman had anything to do ' + 'with this, you would get nowhere fast.';
Use
===
and!==
rather than==
and!=
.
Grammar standards
Choose quadruple spacing or double spacing for indentation according to your own habits and the primary code writer's format.
// bad function() { ∙var name; } // very bad function() { ∙∙<tab>∙∙var name; } // good function() { ∙∙var name; } // good function() { ∙∙∙∙var name; }
Do not leave spaces at the end of the line. Leave an empty line at the bottom of the file
// bad function () {∙ ∙∙∙∙var name;∙ } /* EOF */ // good function () { ∙∙∙∙var name; } /* EOF */
Please add
;
at the end of the statement.// bad proto.foo = function () { } // good proto.foo = function () { }; // very bad function foo () { return 'test' } // good function foo () { return 'test'; } // bad function foo () { }; // good, this is not the end of the statement function foo () { }
Try to put
{
and the expression in the same line// bad if ( isFoobar ) { } // good if ( isFoobar ) { } // bad function foobar() { } // good function foobar() { } // bad var obj = { foo: 'foo', bar: 'bar', } // good var obj = { foo: 'foo', bar: 'bar', }
Put a space before
{
// bad if (isJedi){ fight(); } else{ escape(); } // good if (isJedi) { fight(); } else { escape(); } // bad dog.set('attr',{ age: '1 year', breed: 'Bernese Mountain Dog', }); // good dog.set('attr', { age: '1 year', breed: 'Bernese Mountain Dog', });
Please put a space before
(
of the logic state expressions (if
,else
,while
,switch
)// bad if(isJedi) { fight (); } else{ escape(); } // good if (isJedi) { fight(); } else { escape(); }
Leave one space between the binary ternary operators
// bad var x=y+5; var left = rotated? y: x; // good var x = y + 5; var left = rotated ? y : x; // bad for (let i=0; i< 10; i++) { } // good for (let i = 0; i < 10; i++) { }
The way some functions are declared
// bad var test = function () { console.log('test'); }; // good function test () { console.log('test'); } // bad function divisibleFunction () { return DEBUG ? 'foo' : 'bar'; } // good var divisibleFunction = DEBUG ? function () { return 'foo'; } : function () { return 'bar'; }; // bad function test(){ } // good function test () { } // bad var obj = { foo: function () { } }; // good var obj = { foo () { } }; // bad array.map(x=>x + 1); array.map(x => { return x + 1; }); // good array.map(x => x + 1);
Put a space between Block definitions
// bad if (foo) { return bar; } return baz; // good if (foo) { return bar; } return baz; // bad const obj = { x: 0, y: 0, foo() { }, bar() { }, }; return obj; // good const obj = { x: 0, y: 0, foo() { }, bar() { }, }; return obj;
Do not use a comma to define
// bad var story = [ once , upon , aTime ]; // good var story = [ once, upon, aTime, ]; // bad var hero = { firstName: 'Ada' , lastName: 'Lovelace' , birthYear: 1815 , superPower: 'computers' }; // good var hero = { firstName: 'Ada', lastName: 'Lovelace', birthYear: 1815, superPower: 'computers', };
Single line comments, please add a space after the slash
//bad // good
Multiline comments
/* * good */
A multiline comments that needs to be exported to the API document
/** * good */