better grid.(x|y)side defaults for splom

Author: etpinard

src/components/grid/index.js

@@ -185,6 +185,10 @@ function sizeDefaults(layoutIn, layoutOut) {
     var hasSubplotGrid = Array.isArray(gridIn.subplots) && Array.isArray(gridIn.subplots[0]);
     var hasXaxes = Array.isArray(xAxes);
     var hasYaxes = Array.isArray(yAxes);
+    var isSplomGenerated = (
+        hasXaxes && xAxes !== gridIn.xaxes &&
+        hasYaxes && yAxes !== gridIn.yaxes
+    );
 
     var dfltRows, dfltColumns;
 
@@ -217,17 +221,26 @@ function sizeDefaults(layoutIn, layoutOut) {
     var rowOrder = coerce('roworder');
     var reversed = rowOrder === 'top to bottom';
 
+    var dfltGapX = hasSubplotGrid ? 0.2 : 0.1;
+    var dfltGapY = hasSubplotGrid ? 0.3 : 0.1;
+
+    var dfltSideX, dfltSideY;
+    if(isSplomGenerated) {
+        dfltSideX = 'bottom';
+        dfltSideY = 'left';
+    }
+
     gridOut._domains = {
-        x: fillGridPositions('x', coerce, hasSubplotGrid ? 0.2 : 0.1, columns),
-        y: fillGridPositions('y', coerce, hasSubplotGrid ? 0.3 : 0.1, rows, reversed)
+        x: fillGridPositions('x', coerce, dfltGapX, dfltSideX, columns),
+        y: fillGridPositions('y', coerce, dfltGapY, dfltSideY, rows, reversed)
     };
 }
 
 // coerce x or y sizing attributes and return an array of domains for this direction
-function fillGridPositions(axLetter, coerce, dfltGap, len, reversed) {
+function fillGridPositions(axLetter, coerce, dfltGap, dfltSide, len, reversed) {
     var dirGap = coerce(axLetter + 'gap', dfltGap);
     var domain = coerce('domain.' + axLetter);
-    coerce(axLetter + 'side');
+    coerce(axLetter + 'side', dfltSide);
 
     var out = new Array(len);
     var start = domain[0];

test/image/mocks/splom_upper.json

@@ -694,10 +694,6 @@
   "layout": {
 	"title": "Iris dataset splom",
   	"width": 600,
-	"height": 500,
-    "grid": {
-      "xside": "bottom",
-      "yside": "left"
-    }
+	"height": 500
   }
 }

test/jasmine/tests/splom_test.js

@@ -80,6 +80,37 @@ describe('Test splom trace defaults:', function() {
         expect(subplots.cartesian).toEqual(['xy', 'xy2', 'x2y', 'x2y2']);
     });
 
+    it('should use special `grid.xside` and `grid.yside` defaults on splom generated grids', function() {
+        var gridOut;
+
+        _supply({
+            dimensions: [
+                {values: [1, 2, 3]},
+                {values: [2, 1, 2]}
+            ]
+        });
+
+        gridOut = gd._fullLayout.grid;
+        expect(gridOut.xside).toBe('bottom');
+        expect(gridOut.yside).toBe('left');
+
+        _supply({
+            dimensions: [
+                {values: [1, 2, 3]},
+                {values: [2, 1, 2]}
+            ]
+        }, {
+            grid: {
+                xaxes: ['x', 'x2'],
+                yaxes: ['y', 'y2']
+            }
+        });
+
+        gridOut = gd._fullLayout.grid;
+        expect(gridOut.xside).toBe('bottom plot');
+        expect(gridOut.yside).toBe('left plot');
+    });
+
     it('should honor `grid.xaxes` and `grid.yaxes` settings', function() {
         _supply({
             dimensions: [