code.delx.au - gnu-emacs-elpa/blob - NEWS.md

   1 # History of user-visible changes
   2
   3 ## Next
   4
   5 * Object properties are highlighted using a different face:
   6   `js2-object-property`, which has no color by default.
   7 * `js2-getter-setter-node` is renamed to `js2-method-node`, together
   8   with its related functions.  It already handles generator methods,
   9   and will in the future add support for async methods, so the old
  10   name will get more confusing.
  11 * Support for default parameters in destructuring.  It should work for both
  12   objects and arrays, in both literals and function arguments.
  13 * New mode: `js2-jsx-mode`, deriving from `js2-mode`.  Supports indentation of
  14   JSXElement expressions wrapped within parentheses or as function arguments.
  15   Indentation is customizable via `sgml-attribute-offset`.
  16
  17 ## 20150909
  18
  19 * `js2-mode` now derives from `js-mode`. That means the former
  20   function will run `js-mode-hook`, as well as `js2-mode-hook`. The
  21   key bindings will default to `js-mode-map` where they're not set in
  22   `js2-mode-map`. And in Emacs 25 or later (including the snapshot
  23   builds), `js2-mode` uses the indentation code from `js-mode`.  Where
  24   feasible, the user options (and functions) now have aliases, but if
  25   you're using Emacs 25 and you see an indentation-related setting
  26   that stopped working, try looking for a corresponding one in the
  27   `js` group: `M-x customize-group RET js RET`.
  28
  29 * New command: `js2-jump-to-definition`. It's bound to `M-.` by
  30   default, via remapping `js-find-symbol`. To get back to the default
  31   `M-.` binding (e.g. `find-tag`), put this in your init file:
  32
  33       (eval-after-load 'js (define-key js-mode-map (kbd "M-.") nil))
  34
  35 ## 20150713
  36
  37 * More comprehensive strict mode warnings and syntax errors.
  38 * New minor mode: `js2-highlight-unused-variables-mode`.
  39 * `js2-pretty-multiline-declarations` can take the value `dynamic` now.
  40
  41 ## 20150202
  42
  43 Support for:
  44
  45 * [ES6 modules](http://www.2ality.com/2014/09/es6-modules-final.html).
  46 * [Short-hand object literals](http://ariya.ofilabs.com/2013/02/es6-and-object-literal-property-value-shorthand.html).
  47 * [Method definitions](http://ariya.ofilabs.com/2013/03/es6-and-method-definitions.html).
  48 * ['u' and 'y' RegExp flags](https://mathiasbynens.be/notes/es6-unicode-regex).
  49 * [Computed property names](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-object-initializer).
  50 * [Class statements and expressions](https://github.com/lukehoban/es6features#classes).
  51 * [Template strings](http://tc39wiki.calculist.org/es6/template-strings/), including tagged ones.
  52
  53 The variable `js2-allow-keywords-as-property-names` has been
  54 removed. Instead we check if `js2-language-version` is 180 or highter.
  55
  56 ## 20141115
  57
  58 Support for:
  59
  60 * Unicode characters in identifiers (improved).
  61 * [Delegating yield](http://wiki.ecmascript.org/doku.php?id=harmony:generators#delegating_yield).
  62 * [ES6 numeric literals](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-literals-numeric-literals) (octal, binary).
  63 * Harmony [array and generator comprehensions](http://wingolog.org/archives/2014/03/07/es6-generator-and-array-comprehensions-in-spidermonkey).
  64
  65 ## 20131106
  66
  67 Support for:
  68
  69 * [Arrow functions](http://wiki.ecmascript.org/doku.php?id=harmony:arrow_function_syntax)
  70 * [Generators](http://wiki.ecmascript.org/doku.php?id=harmony:generators)
  71 * [Spread operator](http://wiki.ecmascript.org/doku.php?id=harmony:spread)
  72
  73 ## 20130510
  74
  75 ### Support for JSLint global declaration
  76
  77 See the docstring for `js2-include-jslint-globals`.
  78
  79 ## 20130216
  80
  81 ### We don't rebind `RET` anymore
  82
  83 Because well-behaving major modes aren't supposed to do that.
  84
  85 So pressing it won't continue a block comment, or turn a string into a concatenation.
  86 Pressing `M-j`, however, will.
  87
  88 The options `js2-indent-on-enter-key` and `js2-enter-indents-newline` were also removed.
  89
  90 To bring back the previous behavior, put this in your init file:
  91
  92 ```js
  93 (eval-after-load 'js2-mode
  94   '(define-key js2-mode-map (kbd "RET") 'js2-line-break))
  95 ```
  96
  97 ## 20120617
  98
  99 ### Support for [default](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/default_parameters) and [rest](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/rest_parameters) parameters
 100
 101 ## 20120614
 102
 103 ### Support for [for..of loops](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of)
 104
 105 ## Older changes
 106
 107 ### Popular indentation style
 108
 109 ```js
 110 [foo, bar, baz].forEach(function (v) {
 111     if (validate(v))
 112         process(v);
 113 });
 114
 115 [a, b, c].some(function (v) {
 116     return validate(v);
 117 });
 118 ```
 119
 120 ### Pretty multiline variable declaration
 121
 122 In the original mode,
 123
 124 ```js
 125 var foo = 10,
 126 bar = 20,
 127 baz = 30;
 128 ```
 129
 130 In this mode when the value of `js2-pretty-multiline-declarations` is non-nil,
 131
 132 ```js
 133 var foo = 10,
 134     bar = 20,
 135     baz = 30;
 136 ```
 137
 138 ### Abbreviated destructuring assignments
 139
 140 ```js
 141 let {a, b}       = {a: 10, b: 20}; // Abbreviated   (Not supported in the original mode)
 142 let {a: a, b: b} = {a: 10, b: 20}; // Same as above (Supported in the original mode)
 143
 144 (function ({responseText}) { /* */ })(xhr); // As the argument of function
 145
 146 for (let [k, { name, age }] in Iterator(obj)) // nested
 147     print(k, name, age);
 148 ```
 149
 150 ### Expression closure in property value
 151
 152 ```js
 153 let worker = {
 154     get age() 20,
 155     get sex() "male",
 156     fire: function () _fire()
 157 };
 158 ```
 159
 160 ### Fix for odd indentation of "else if" with no braces
 161
 162 In the original mode,
 163
 164 ```js
 165 if (foo)
 166     return foo;
 167 else if (bar)
 168 return bar;      // here
 169 ```
 170
 171 In this mode,
 172
 173 ```js
 174 if (foo)
 175     return foo;
 176 else if (bar)
 177     return bar;  // fixed
 178 ```
 179
 180 ### Imenu support for function nesting
 181
 182 Supports function nesting and anonymous wrappers:
 183
 184 ```js
 185 (function() {
 186   var foo = function() {
 187     function bar() { // shown as foo.bar.<definition-1>
 188       function baz() {} // foo.bar.baz
 189       var qux = function() {}; // foo.bar.quux
 190     }
 191   };
 192 });
 193 ```
 194
 195 Examples of output:
 196
 197 * [jQuery 1.5](https://gist.github.com/845449)
 198 * [Underscore.js](https://gist.github.com/824262)
 199 * [Backbone.js](https://gist.github.com/824260)
 200
 201 For library-specific extension methods like `$.extend` and `dojo.declare`, see [js2-imenu-extras](/mooz/js2-mode/blob/master/js2-imenu-extras.el).
 202
 203 ### Undeclared/external variables highlighting
 204
 205 Original mode highlights them only on the left side of assignments:
 206
 207 ```js
 208 var house;
 209 hose = new House(); // highlights "hose"
 210 ```
 211
 212 Here they are highlighted in all expressions:
 213
 214 ```js
 215 function feed(fishes, food) {
 216     for each (var fish in fshes) { // highlights "fshes"
 217         food.feed(fsh); // highlights "fsh"
 218     }
 219     hood.discard(); // highlights "hood"
 220 }
 221 ```
 222
 223 Destructuring assignments and array comprehensions (JS 1.7) are supported:
 224
 225 ```js
 226 let three, [one, two] = [1, 2];
 227 thee = one + two; // highlights "thee"
 228
 229 function revenue(goods) {
 230     // highlights "coast"
 231     return [price - coast for each ({price, cost} in goods)].reduce(add);
 232 }
 233 ```