Add sortShapeProp option to sort-prop-types rule

This allows the rule to enforce the sorting rules in a shape prop
object.

Author: jomasti

docs/rules/sort-prop-types.md

@@ -80,6 +80,7 @@ class Component extends React.Component {
   "callbacksLast": <boolean>,
   "ignoreCase": <boolean>,
   "requiredFirst": <boolean>,
+  "sortShapeProp": <boolean>
 }]
 ...
 ```
@@ -120,6 +121,25 @@ var Component = createReactClass({
 });
 ```
 
+### `sortShapeProp`
+
+When `true`, props defined in `PropTypes.shape` must be sorted via the same rules as the top-level props:
+
+```js
+var Component = createReactClass({
+  propTypes: {
+    a: PropTypes.number,
+    b: PropTypes.shape({
+      d: PropTypes.number,
+      e: PropTypes.func,
+      f: PropTypes.bool,
+    }),
+    c: PropTypes.string,
+  },
+...
+});
+```
+
 ## When not to use
 
 This rule is a formatting preference and not following it won't negatively affect the quality of your code. If alphabetizing props declarations isn't a part of your coding standards, then you can leave this rule off.

lib/rules/sort-prop-types.js

@@ -28,6 +28,9 @@ module.exports = {
         },
         ignoreCase: {
           type: 'boolean'
+        },
+        sortShapeProp: {
+          type: 'boolean'
         }
       },
       additionalProperties: false
@@ -40,6 +43,7 @@ module.exports = {
     const requiredFirst = configuration.requiredFirst || false;
     const callbacksLast = configuration.callbacksLast || false;
     const ignoreCase = configuration.ignoreCase || false;
+    const sortShapeProp = configuration.sortShapeProp || false;
     const propWrapperFunctions = new Set(context.settings.propWrapperFunctions || []);
 
     /**
@@ -78,6 +82,12 @@ module.exports = {
       return getValueName(node) === 'isRequired';
     }
 
+    function isShapeProp(node) {
+      return Boolean(
+        node && node.callee && node.callee.property && node.callee.property.name === 'shape'
+      );
+    }
+
     /**
      * Find a variable by name in the current scope.
      * @param  {string} name Name of the variable to look for.
@@ -185,6 +195,13 @@ module.exports = {
     }
 
     return {
+      CallExpression: function(node) {
+        if (!sortShapeProp || !isShapeProp(node) || (!node.arguments && !node.arguments[0])) {
+          return;
+        }
+        checkSorted(node.arguments[0].properties);
+      },
+
       ClassProperty: function(node) {
         if (!isPropTypesDeclaration(node)) {
           return;