refactor(lint):: enable eqeqeq rule except for null (#1638)

.eslintrc.json

@@ -12,6 +12,13 @@
         "allowImplicit": true
       }
     ],
+    "eqeqeq": [
+      "error",
+      "always",
+      {
+        "null": "ignore"
+      }
+    ],
     "no-lonely-if": 2,
     "no-proto": 2,
     "curly": [2, "multi-line"],

lib/api/attributes.js

@@ -383,10 +383,10 @@ exports.val = function (value) {
       var option = this.find('option:selected');
       if (!option) return;
       if (!querying) {
-        if (this.attr('multiple') == null && typeof value == 'object') {
+        if (this.attr('multiple') == null && typeof value === 'object') {
           return this;
         }
-        if (typeof value != 'object') {
+        if (typeof value !== 'object') {
           value = [value];
         }
         this.find('option').removeAttr('selected');

lib/api/css.js

@@ -38,7 +38,7 @@ exports.css = function (prop, val) {
  * @param {number} [idx] - Optional index within the selection.
  */
 function setCss(el, prop, val, idx) {
-  if (typeof prop == 'string') {
+  if (typeof prop === 'string') {
     var styles = getCss(el);
     if (typeof val === 'function') {
       val = val.call(el, idx, styles[prop]);
@@ -51,7 +51,7 @@ function setCss(el, prop, val, idx) {
     }
 
     el.attribs.style = stringify(styles);
-  } else if (typeof prop == 'object') {
+  } else if (typeof prop === 'object') {
     Object.keys(prop).forEach(function (k) {
       setCss(el, k, prop[k]);
     });