Improve documentation and simplify syntax

Author: hannahker

src/plots/cartesian/layout_attributes.js

@@ -1020,6 +1020,8 @@ module.exports = {
         editType: 'plot',
         description: [
             'Moves the axis a given number of pixels from where it would have been otherwise.',
+            'Accepts both positive and negative values, which will shift the axis either right',
+            'or left, respectively.',
             'If `autoshift=true`, then this defaults to a padding of `-3` if `side=left`',
             'and `+3` if `side=right`. Defaults to `0` if `autoshift=false`.',
             'Only has an effect if `anchor` is set to *free*.'

src/plots/plots.js

@@ -1960,14 +1960,10 @@ function needsRedrawForShift(gd) {
         return false;
     }
     var axList = axisIDs.list(gd, '', true);
-    var isShift = false;
     for(var ax in axList) {
-        if(isShift === true) {
-            return isShift;
-        }
-        isShift = (axList[ax].autoshift === true || axList[ax].shift !== undefined) ? true : false;
+        if(axList[ax].autoshift || axList[ax].shift !== undefined) return true;
     }
-    return isShift;
+    return false;
 }
 
 plots.doAutoMargin = function(gd) {

test/plot-schema.json

@@ -10742,7 +10742,7 @@
      "valType": "boolean"
     },
     "shift": {
-     "description": "Moves the axis a given number of pixels from where it would have been otherwise. If `autoshift=true`, then this defaults to a padding of `-3` if `side=left` and `+3` if `side=right`. Defaults to `0` if `autoshift=false`. Only has an effect if `anchor` is set to *free*.",
+     "description": "Moves the axis a given number of pixels from where it would have been otherwise. Accepts both positive and negative values, which will shift the axis either right or left, respectively. If `autoshift=true`, then this defaults to a padding of `-3` if `side=left` and `+3` if `side=right`. Defaults to `0` if `autoshift=false`. Only has an effect if `anchor` is set to *free*.",
      "editType": "plot",
      "valType": "number"
     },
@@ -11750,7 +11750,7 @@
      "valType": "boolean"
     },
     "shift": {
-     "description": "Moves the axis a given number of pixels from where it would have been otherwise. If `autoshift=true`, then this defaults to a padding of `-3` if `side=left` and `+3` if `side=right`. Defaults to `0` if `autoshift=false`. Only has an effect if `anchor` is set to *free*.",
+     "description": "Moves the axis a given number of pixels from where it would have been otherwise. Accepts both positive and negative values, which will shift the axis either right or left, respectively. If `autoshift=true`, then this defaults to a padding of `-3` if `side=left` and `+3` if `side=right`. Defaults to `0` if `autoshift=false`. Only has an effect if `anchor` is set to *free*.",
      "editType": "plot",
      "valType": "number"
     },