disallow constraining AND matching range

Author: etpinard

Diff for: src/plots/cartesian/constraints.js

@@ -30,7 +30,7 @@ exports.handleConstraintDefaults = function(containerIn, containerOut, coerce, a
 
     // coerce the constraint mechanics even if this axis has no scaleanchor
     // because it may be the anchor of another axis.
-    coerce('constrain');
+    var constrain = coerce('constrain');
     Lib.coerce(containerIn, containerOut, {
         constraintoward: {
             valType: 'enumerated',
@@ -58,6 +58,13 @@ exports.handleConstraintDefaults = function(containerIn, containerOut, coerce, a
         }
     }, 'matches');
 
+    // disallow constraining AND matching range
+    if(constrain === 'range' && scaleanchor === matches) {
+        delete containerOut.scaleanchor;
+        delete containerOut.constrain;
+        scaleanchor = null;
+    }
+
     var found = false;
 
     if(scaleanchor) {

Diff for: test/jasmine/tests/axes_test.js

@@ -689,6 +689,24 @@ describe('Test axes', function() {
             });
         });
 
+        it('disallow constraining AND matching range', function() {
+            layoutIn = {
+                xaxis: {},
+                xaxis2: {matches: 'x', scaleanchor: 'x'}
+            };
+            layoutOut._subplots.cartesian.push('x2y');
+            layoutOut._subplots.xaxis.push('x2');
+
+            supplyLayoutDefaults(layoutIn, layoutOut, fullData);
+
+            expect(layoutOut.xaxis2.matches).toBe('x');
+            expect(layoutOut.xaxis2.scaleanchor).toBe(undefined);
+            expect(layoutOut.xaxis2.constrain).toBe(undefined);
+
+            expect(layoutOut._axisConstraintGroups).toEqual([]);
+            expect(layoutOut._axisMatchGroups).toEqual([{x: 1, x2: 1}]);
+        });
+
         it('drops scaleanchor settings if either the axis or target has fixedrange', function() {
             // some of these will create warnings... not too important, so not going to test,
             // just want to keep the output clean