Added the detection for remove-empty-rulesets option

Author: kizu

lib/options/remove-empty-rulesets.js

@@ -80,6 +80,22 @@ module.exports = {
 
     _isWhitespace: function(node) {
         return node[0] === 's';
-    }
+    },
+
+    /**
+     * Detects the syntax at the tree node.
+     * This option is treated as `true` by default, but any trailing space would invalidate it.
+     *
+     * @param {String} nodeType
+     * @param {node} node
+     */
+    _detectDefault: true,
 
+    detect: function(nodeType, node) {
+        if (nodeType === 'atrulers' || nodeType === 'block') {
+            if (node.length === 0 || (node.length === 1 && node[0][0] === 's')) {
+                return false;
+            }
+        }
+    }
 };

test/integral.js

@@ -38,6 +38,7 @@ describe('integral test', function() {
                 assert.equal(
                     JSON.stringify(comb.processString(results[1])),
                     JSON.stringify({
+                        'remove-empty-rulesets': true,
                         'always-semicolon': true,
                         'color-case': 'lower',
                         'color-shorthand': true,

test/remove-empty-rulesets.js

@@ -35,6 +35,97 @@ describe('options/remove-empty-rulesets', function() {
             assert.equal(comb.processString('a { /* comment */ }\nb {} '), 'a { /* comment */ }\n ');
         });
     });
+
+    describe('detecting the value', function() {
+        // Helper to check the detection
+        function should_detect(options, a, b) {
+            comb.detect(options);
+            assert.equal(
+                JSON.stringify(comb.processString(a)),
+                JSON.stringify(b)
+            );
+        }
+
+        it('Should detect this option set to `true`', function() {
+            should_detect(
+                ['remove-empty-rulesets'],
+                'a { color: red }',
+                {
+                    'remove-empty-rulesets': true
+                }
+            );
+        });
+
+        it('Should detect this option set to `false` with empty block', function() {
+            should_detect(
+                ['remove-empty-rulesets'],
+                'a {}',
+                {
+                    'remove-empty-rulesets': false
+                }
+            );
+        });
+
+        it('Should detect this option set to `false` with block containing whitespace', function() {
+            should_detect(
+                ['remove-empty-rulesets'],
+                'a {   }',
+                {
+                    'remove-empty-rulesets': false
+                }
+            );
+        });
+
+        it('Should detect this option set to `true` with block containing comment', function() {
+            should_detect(
+                ['remove-empty-rulesets'],
+                'a { /* Hello */ }',
+                {
+                    'remove-empty-rulesets': true
+                }
+            );
+        });
+
+        it('Should detect this option set to `true` with media query containing block', function() {
+            should_detect(
+                ['remove-empty-rulesets'],
+                '@media all and (min-width:0) { a { /* Hello */ } }',
+                {
+                    'remove-empty-rulesets': true
+                }
+            );
+        });
+
+        it('Should detect this option set to `true` with media query containing comment', function() {
+            should_detect(
+                ['remove-empty-rulesets'],
+                '@media all and (min-width:0) {/* Hello */}',
+                {
+                    'remove-empty-rulesets': true
+                }
+            );
+        });
+
+        it('Should detect this option set to `false` with empty media query', function() {
+            should_detect(
+                ['remove-empty-rulesets'],
+                '@media all and (min-width:0) {}',
+                {
+                    'remove-empty-rulesets': false
+                }
+            );
+        });
+
+        it('Should detect this option set to `false` with media query containing whitespace', function() {
+            should_detect(
+                ['remove-empty-rulesets'],
+                '@media all and (min-width:0) { \n  }',
+                {
+                    'remove-empty-rulesets': false
+                }
+            );
+        });
+    });
 });
 
 describe('options/remove-empty-rulesets AST manipulation', function() {