Block indent: Change acceptable values

`block-indent` option now accepts only these kind of values:
    - `{Number}` of spaces;
    - `{String}` of whitespaces and tabs. If there is any other character in the
      string, the value will not be set.

Author: tonyganch

.csscomb.json

@@ -4,7 +4,7 @@
         "node_modules/**"
     ],
     "always-semicolon": true,
-    "block-indent": true,
+    "block-indent": "    ",
     "colon-space": true,
     "color-case": "lower",
     "color-shorthand": true,

README.md

@@ -149,7 +149,7 @@ Example configuration:
     "verbose": true,
 
     "always-semicolon": true,
-    "block-indent": true,
+    "block-indent": "    ",
     "colon-space": true,
     "color-case": "lower",
     "color-shorthand": true,
@@ -330,10 +330,10 @@ div {
 
 **Note**: better to use with [rule-indent](#rule-indent)
 
-Available values:
-  * `{Boolean}` `true` (means 4 spaces)
-  * `{Number}` of spaces
-  * `{String}` of whitespace characters (`/[ \t]+/`)
+Acceptable values:
+  * `{Number}` of spaces;
+  * `{String}` of whitespaces or tabs. If there is any other character in the
+    string, the value will not be set.
 
 Example: `{ "block-indent": 2 }`
 
@@ -351,6 +351,23 @@ a { color: red
 }
 ```
 
+Example: `{ "block-indent": "  " }`
+
+```css
+/* before */
+  a { color: red }
+  @media all { a { color: green } }
+
+/* after */
+a { color: red
+}
+@media all {
+  a { color: green
+  }
+}
+```
+
+
 ### colon-space
 
 Available values:

lib/options/block-indent.js

@@ -3,15 +3,18 @@ module.exports = {
     /**
      * Sets handler value.
      *
-     * @param {String|Number|Boolean} value Option value
+     * @param {String|Number} value Option value
      * @returns {Object|undefined}
      */
     setValue: function(value) {
         delete this._value;
-        if (value === true) this._value = '    ';
-        if (typeof value === 'number' && value === Math.abs(Math.round(value)))
+
+        if (typeof value === 'number' && value === Math.abs(Math.round(value))) {
             this._value = new Array(value + 1).join(' ');
-        if (typeof value === 'string' && value.match(/^[ \t]+$/)) this._value = value;
+        } else if (typeof value === 'string' && value.match(/^[ \t]+$/)) {
+            this._value = value;
+        }
+
         if (typeof this._value === 'string') return this;
     },
 

test/block-indent.js

@@ -3,30 +3,29 @@ var assert = require('assert');
 
 describe('options/block-indent', function() {
     var comb;
+
     beforeEach(function() {
         comb = new Comb();
     });
+
     it('Invalid Number value should not change space after brace', function() {
+        var input = 'a { color: red }';
         comb.configure({ 'block-indent': 3.5 });
-        assert.equal(
-            comb.processString('a { color: red }'),
-            'a { color: red }'
-        );
+        assert.equal(comb.processString(input), input);
     });
+
     it('Invalid String value should not change space after brace', function() {
+        var input = 'a { color: red }';
         comb.configure({ 'block-indent': 'foobar' });
-        assert.equal(
-            comb.processString('a { color: red }'),
-            'a { color: red }'
-        );
+        assert.equal(comb.processString(input), input);
     });
-    it('True Boolean value should set 4 spaces indent', function() {
+
+    it('Boolean value should not change space after brace', function() {
+        var input = ' \n a { color: red }  @media all {.input__control { color: #000;\n}\n}';
         comb.configure({ 'block-indent': true });
-        assert.equal(
-            comb.processString(' \n a { color: red }  @media all {.input__control { color: #000;\n}\n}'),
-            ' \na { color: red \n}\n@media all {\n    .input__control { color: #000;\n    }\n}'
-        );
+        assert.equal(comb.processString(input), input);
     });
+
     it('Valid Number value should set equal space after brace', function() {
         comb.configure({ 'block-indent': 3 });
         assert.equal(