feat(polar) about ISSUE 11452

src/chart/bar/BarView.js

@@ -424,8 +424,8 @@ function updateStyle(
 
     el.useStyle(zrUtil.defaults(
         {
-            fill: color,
-            opacity: opacity
+            fill: layout.startAngle === layout.endAngle ? 'transparent' : color,
+            opacity: layout.startAngle === layout.endAngle ? 0 : opacity
         },
         itemStyleModel.getBarItemStyle()
     ));

src/chart/gauge/GaugeSeries.js

@@ -19,7 +19,6 @@
 
 import createListSimply from '../helper/createListSimply';
 import SeriesModel from '../../model/Series';
-import * as zrUtil from 'zrender/src/core/util';
 
 var GaugeSeries = SeriesModel.extend({
 

src/coord/polar/polarCreator.js

@@ -50,7 +50,7 @@ function resizePolar(polar, polarModel, api) {
 
     var radius = polarModel.get('radius');
     if (radius == null) {
-        radius = [0, "100%"];
+        radius = [0, '100%'];
     }
     else if (!zrUtil.isArray(radius)) {
         // r0 = 0

test/polar-rounded.html

@@ -186,7 +186,7 @@ under the License.
                 },
                 series: [{
                     type: 'bar',
-                    data: [1],
+                    data: [0],
                     coordinateSystem: 'polar',
                     name: 'A',
                     roundCap: true,