#286: Remove percent sign for zero-values percentages when safe

.gitignore

@@ -1,2 +1,3 @@
 /node_modules/
 /coverage/
+.idea

lib/replace/Dimension.js

@@ -21,13 +21,87 @@ var LENGTH_UNIT = {
     'vmax': true,
     'vm': true
 };
+var PERCENTAGE_LENGTH_DELC = {
+    'margin': true,
+    'margin-top': true,
+    'margin-left': true,
+    'margin-bottom': true,
+    'margin-right': true,
+
+    'padding': true,
+    'padding-top': true,
+    'padding-left': true,
+    'padding-bottom': true,
+    'padding-right': true,
+
+    'top': true,
+    'left': true,
+    'botton': true,
+    'right': true,
+    'position': true,
+
+    '-webkit-mask-box-image': true,
+    '-webkit-mask-position-x': true,
+    '-webkit-mask-position-y': true,
+
+    'background-position-x': true,
+    'background-position-y': true,
+
+    'border': true,
+    'border-width': true,
+    'border-top-width': true,
+    'border-left-width': true,
+    'border-bottom-width': true,
+    'border-right-width': true,
+    'border-image-width': true,
+
+    'border-radius': true,
+    'border-bottom-left-radius': true,
+    'border-bottom-right-radius': true,
+    'border-top-left-radius': true,
+    'border-top-right-radius': true,
+
+    'font-size': true,
+    'grid-column-gap': true,
+    'grid-row-gap': true,
+    'letter-spacing': true,
+    'offset-distance': true,
+    'scroll-snap-points-x': true,
+    'scroll-snap-points-y': true,
+    'shape-margin': true,
+    'text-indent': true,
+    'transform-origin': true,
+    'word-spacing': true
+};
+
+var PERCENTAGE_LENGTH_FN = {
+    'inset': true,
+    'polygon': true,
+    'translate': true,
+    'translate3d': true,
+    'translateX': true,
+    'translateY': true
+};
 
 module.exports = function compressDimension(node, item) {
     var value = packNumber(node.value, item);
+    var decl = this.declaration !== null ? this.declaration.property : null;
+    var fnName = this['function'] !== null ? this['function'].name : null;
 
     node.value = value;
 
-    if (value === '0' && this.declaration !== null && this.atrulePrelude === null) {
+    if (node.type === 'Percentage') {
+        if (PERCENTAGE_LENGTH_DELC.hasOwnProperty(decl) || PERCENTAGE_LENGTH_FN.hasOwnProperty(fnName)) {
+            // Zero-value workaround
+            if (value === '0') {
+                item.data = {
+                    type: 'Number',
+                    loc: node.loc,
+                    value: value
+                };
+            }
+        }
+    } else if (value === '0' && decl !== null && this.atrulePrelude === null) {
         var unit = node.unit.toLowerCase();
 
         // only length values can be compressed
@@ -36,12 +110,12 @@ module.exports = function compressDimension(node, item) {
         }
 
         // issue #200: don't remove units in flex property as it could change value meaning
-        if (this.declaration.property === 'flex') {
+        if (decl === 'flex') {
             return;
         }
 
         // issue #222: don't remove units inside calc
-        if (this['function'] && this['function'].name === 'calc') {
+        if (fnName === 'calc') {
             return;
         }
 

lib/replace/index.js

@@ -4,7 +4,7 @@ var handlers = {
     AttributeSelector: require('./AttributeSelector'),
     Value: require('./Value'),
     Dimension: require('./Dimension'),
-    Percentage: require('./Number'),
+    Percentage: require('./Dimension'),
     Number: require('./Number'),
     String: require('./String'),
     Url: require('./Url'),

test/fixture/compress/restructure.margin/4.css

@@ -0,0 +1,6 @@
+.a {
+	margin: 0%
+}
+.b {
+	margin: 0% 0px 0em 0rem
+}

test/fixture/compress/restructure.margin/4.min.css

@@ -0,0 +1 @@
+.a,.b{margin:0}