Adds --skip-restructuring / restructuring switches.

Adds a CLI & API switches to turn off restructuring, which is on
by default.

README.md

@@ -60,6 +60,7 @@ cleancss [options] source-file, [source-file, ...]
                                 reduction, etc.
 --skip-aggressive-merging       Disable properties merging based on their order
 --skip-media-merging            Disable `@media` merging
+--skip-restructuring            Disable restructuring optimizations
 --skip-shorthand-compacting     Disable shorthand compacting
 --rounding-precision [N]        Rounds to `N` decimal places. Defaults to 2. -1 disables rounding.
 -c, --compatibility [ie7|ie8]   Force compatibility mode (see Readme for advanced examples)
@@ -123,6 +124,7 @@ CleanCSS constructor accepts a hash as a parameter, i.e.,
 * `processImport` - whether to process `@import` rules
 * `rebase` - set to false to skip URL rebasing
 * `relativeTo` - path to __resolve__ relative `@import` rules and URLs
+* `restructuring` - set to false to disable restructuring in advanced optimizations
 * `root` - path to __resolve__ absolute `@import` rules and __rebase__ relative URLs
 * `roundingPrecision` - rounding precision; defaults to `2`; `-1` disables rounding
 * `shorthandCompacting` - set to false to skip shorthand compacting (default is true unless sourceMap is set when it's false)

bin/cleancss

@@ -26,6 +26,7 @@ commands
   .option('--skip-advanced', 'Disable advanced optimizations - selector & property merging, reduction, etc.')
   .option('--skip-aggressive-merging', 'Disable properties merging based on their order')
   .option('--skip-media-merging', 'Disable @media merging')
+  .option('--skip-restructuring', 'Disable restructuring optimizations')
   .option('--skip-shorthand-compacting', 'Disable shorthand compacting')
   .option('--rounding-precision [n]', 'Rounds to `N` decimal places. Defaults to 2. -1 disables rounding.', parseInt)
   .option('-c, --compatibility [ie7|ie8]', 'Force compatibility mode (see Readme for advanced examples)')
@@ -68,6 +69,7 @@ var options = {
   mediaMerging: commands.skipMediaMerging ? false : true,
   processImport: commands.skipImport ? false : true,
   rebase: commands.skipRebase ? false : true,
+  restructuring: commands.skipRestructuring ? false : true,
   root: commands.root,
   roundingPrecision: commands.roundingPrecision,
   shorthandCompacting: commands.skipShorthandCompacting ? false : true,

lib/clean.js

@@ -39,6 +39,7 @@ var CleanCSS = module.exports = function CleanCSS(options) {
     processImport: undefined === options.processImport ? true : !!options.processImport,
     rebase: undefined === options.rebase ? true : !!options.rebase,
     relativeTo: options.relativeTo,
+    restructuring: undefined === options.restructuring ? true : !!options.restructuring,
     root: options.root,
     roundingPrecision: options.roundingPrecision,
     shorthandCompacting: !!options.sourceMap ? false : (undefined === options.shorthandCompacting ? true : !!options.shorthandCompacting),

lib/selectors/optimizers/advanced.js

@@ -718,7 +718,7 @@ AdvancedOptimizer.prototype.optimize = function (tokens) {
     self.mergeNonAdjacentBySelector(tokens);
     self.mergeNonAdjacentByBody(tokens);
 
-    if (withRestructuring) {
+    if (self.options.restructuring && withRestructuring) {
       self.restructure(tokens);
       self.mergeAdjacent(tokens);
     }

test/binary-test.js

@@ -130,6 +130,11 @@ exports.commandsSuite = vows.describe('binary commands').addBatch({
       assert.equal(stdout, 'a{color:red}p{color:red}');
     }
   }),
+  'skip restructuring optimizations': pipedContext('div{margin-top:0}.one{margin:0}.two{display:block;margin-top:0}', '--skip-restructuring', {
+    'should do basic optimizations only': function(error, stdout) {
+      assert.equal(stdout, 'div{margin-top:0}.one{margin:0}.two{display:block;margin-top:0}');
+    }
+  }),
   'no relative to path': binaryContext('./test/fixtures/partials-absolute/base.css', {
     'should not be able to resolve it fully': function(error, stdout, stderr) {
       assert.isEmpty(stdout);

test/module-test.js

@@ -312,6 +312,20 @@ vows.describe('module tests').addBatch({
       'gets right output': function (minified) {
         assert.include(minified.styles, 'url(/test/fixtures/dummy.png)');
       }
+    },
+    'restructuring': {
+      'on': {
+        'topic': new CleanCSS({ restructuring: true }).minify('div{margin-top:0}.one{margin:0}.two{display:block;margin-top:0}'),
+        'gets right output': function (minified) {
+          assert.equal(minified.styles, '.two,div{margin-top:0}.one{margin:0}.two{display:block}');
+        }
+      },
+      'off': {
+        'topic': new CleanCSS({ restructuring: false }).minify('div{margin-top:0}.one{margin:0}.two{display:block;margin-top:0}'),
+        'gets right output': function (minified) {
+          assert.equal(minified.styles, 'div{margin-top:0}.one{margin:0}.two{display:block;margin-top:0}');
+        }
+      }
     }
   },
   'source map': {

test/selectors/optimizer-test.js

@@ -10,6 +10,7 @@ function optimizerContext(group, specs, options) {
   var context = {};
   options = options || {};
   options.shorthandCompacting = true;
+  options.restructuring = true;
   options.compatibility = new Compatibility(options.compatibility).toOptions();
 
   function optimized(target) {