include "sign of arrow starting at axis pointing towards margin"

... into `Axes.getTickSigns` output

Author: etpinard

src/plots/cartesian/axes.js

@@ -1832,7 +1832,6 @@ axes.drawOne = function(gd, ax, opts) {
 
     if(ax.type === 'multicategory') {
         var pad = {x: 2, y: 10}[axLetter];
-        var sgn = {l: -1, t: -1, r: 1, b: 1}[ax.side.charAt(0)];
 
         seq.push(function() {
             var bboxKey = {x: 'height', y: 'width'}[axLetter];
@@ -1846,24 +1845,23 @@ axes.drawOne = function(gd, ax, opts) {
                 repositionOnUpdate: true,
                 secondary: true,
                 transFn: transFn,
-                labelFns: axes.makeLabelFns(ax, mainLinePosition + standoff * sgn)
+                labelFns: axes.makeLabelFns(ax, mainLinePosition + standoff * tickSigns[4])
             });
         });
 
         seq.push(function() {
-            ax._depth = sgn * (getLabelLevelBbox('tick2')[ax.side] - mainLinePosition);
+            ax._depth = tickSigns[4] * (getLabelLevelBbox('tick2')[ax.side] - mainLinePosition);
 
             return drawDividers(gd, ax, {
                 vals: dividerVals,
                 layer: mainAxLayer,
-                path: axes.makeTickPath(ax, mainLinePosition, sgn, ax._depth),
+                path: axes.makeTickPath(ax, mainLinePosition, tickSigns[4], ax._depth),
                 transFn: transFn
             });
         });
     } else if(ax.title.hasOwnProperty('standoff')) {
         seq.push(function() {
-            var sgn = {l: -1, t: -1, r: 1, b: 1}[ax.side.charAt(0)];
-            ax._depth = sgn * (getLabelLevelBbox()[ax.side] - mainLinePosition);
+            ax._depth = tickSigns[4] * (getLabelLevelBbox()[ax.side] - mainLinePosition);
         });
     }
 
@@ -2100,6 +2098,7 @@ function calcLabelLevelBbox(ax, cls) {
  *  - [1]: sign for bottom/left ticks (i.e. positive SVG direction)
  *  - [2]: sign for ticks corresponding to 'ax.side'
  *  - [3]: sign for ticks mirroring 'ax.side'
+ *  - [4]: sign of arrow starting at axis pointing towards margin
  */
 axes.getTickSigns = function(ax) {
     var axLetter = ax._id.charAt(0);
@@ -2110,6 +2109,10 @@ axes.getTickSigns = function(ax) {
     if((ax.ticks !== 'inside') === (axLetter === 'x')) {
         out = out.map(function(v) { return -v; });
     }
+    // independent of `ticks`; do not flip this one
+    if(ax.side) {
+        out.push({l: -1, t: -1, r: 1, b: 1}[ax.side.charAt(0)]);
+    }
     return out;
 };