Refactored for testability.

Author: David Jolly

DeepLinkStateMixin.js

@@ -0,0 +1,71 @@
+'use strict';
+
+var _ = require('lodash');
+
+var DeepLinkedStateLib = {
+    getValueFromState: function(statePath, options) {
+        return DeepLinkedStateLib.getValueFromObject(statePath, options, this.state);
+    },
+    
+    getValueFromObject: function(statePath, options, valueObject) {
+        options = options || {};
+        
+        var value = valueObject;
+        
+        var havePath = _.all(statePath, function(statePathPart) {
+            if (!_.isObject(value) || !value.hasOwnProperty(statePathPart)) {
+                return false;
+            }
+            
+            value = value[statePathPart];
+            
+            return true;
+        });
+        
+        if (!havePath) {
+            value = null;
+        }
+        
+        if (options.storeEmptyStringAsNull) {
+            if (value === null) {
+                value = '';
+            }
+        }
+        
+        return value;
+    },
+
+    onChange: function(statePath, options, value) {
+        var partialState = DeepLinkedStateLib.updateValueObject(statePath, options, value, this.state);
+        
+        this.setState(partialState);
+    },
+
+    updateValueObject: function(statePath, options, value, valueObject) {
+        options = options || {};
+        
+        var statePathDepth = [].concat(statePath);
+        var statePathLast = statePathDepth.pop();
+        
+        var partialState = _.pick(valueObject, statePathDepth[0]);
+        var stateSub = partialState;
+        
+        _.each(statePathDepth, function(statePathPart) {
+            stateSub[statePathPart] = _.extend({}, stateSub[statePathPart]);
+            
+            stateSub = stateSub[statePathPart];
+        });
+        
+        if (options.storeEmptyStringAsNull) {
+            if (value === '') {
+                value = null;
+            }
+        }
+        
+        stateSub[statePathLast] = value;
+        
+        return partialState;
+    }
+};
+
+module.exports = DeepLinkedStateLib;

DeepLinkedStateLib.js

@@ -0,0 +1,16 @@
+'use strict';
+
+var ReactLink = require('react/lib/ReactLink');
+
+var DeepLinkedStateLib = require('./DeepLinkedStateLib');
+
+var DeepLinkedStateMixin = {
+    deepLinkState: function(statePath, options) {
+        return new ReactLink(
+            DeepLinkedStateLib.getValueFromState.call(this, statePath, options),
+            DeepLinkedStateLib.onChange.bind(this, statePath, options)
+        );
+    }
+};
+
+module.exports = DeepLinkedStateMixin;

DeepLinkedStateMixin.js

@@ -27,5 +27,8 @@
   "dependencies": {
     "lodash": "^3.6.0",
     "react": "^0.13.1"
+  },
+  "devDependencies": {
+    "mocha": "^2.2.4"
   }
 }