fix and 🔒 maindrag when polar.hole>0

Author: etpinard

src/plots/polar/polar.js

@@ -629,6 +629,7 @@ proto.updateMainDrag = function(fullLayout) {
     var cyy = _this.cyy;
     var sectorInRad = _this.sectorInRad;
     var vangles = _this.vangles;
+    var radialAxis = _this.radialAxis;
     var clampTiny = helpers.clampTiny;
     var findXYatLength = helpers.findXYatLength;
     var findEnclosingVertexAngles = helpers.findEnclosingVertexAngles;
@@ -840,16 +841,13 @@ proto.updateMainDrag = function(fullLayout) {
 
         dragBox.showDoubleClickNotifier(gd);
 
-        var radialAxis = _this.radialAxis;
         var rl = radialAxis._rl;
-        var drl = rl[1] - rl[0];
-        var updateObj = {};
-        updateObj[_this.id + '.radialaxis.range'] = [
-            rl[0] + r0 * drl / radius,
-            rl[0] + r1 * drl / radius
+        var m = (rl[1] - rl[0]) / (1 - innerRadius / radius) / radius;
+        var newRng = [
+            rl[0] + (r0 - innerRadius) * m,
+            rl[0] + (r1 - innerRadius) * m
         ];
-
-        Registry.call('relayout', gd, updateObj);
+        Registry.call('relayout', gd, _this.id + '.radialaxis.range', newRng);
     }
 
     dragOpts.prepFn = function(evt, startX, startY) {

test/jasmine/tests/polar_test.js

@@ -924,6 +924,13 @@ describe('Test polar interactions:', function() {
             expect(eventCnts.plotly_relayout)
                 .toBe(relayoutNumber, 'no new relayout events after *not far enough* cases');
         })
+        .then(_reset)
+        .then(function() { return Plotly.relayout(gd, 'polar.hole', 0.2); })
+        .then(function() { relayoutNumber++; })
+        .then(function() { return _drag([mid[0] + 30, mid[0] - 30], [50, -50]); })
+        .then(function() {
+            _assertDrag([1.15, 7.70], 'with polar.hole>0, from quadrant #1 move top-right');
+        })
         .catch(failTest)
         .then(done);
     });