Specific function to get value by dot notation

lib/model.js

@@ -231,7 +231,9 @@ function modify (obj, updateQuery) {
 // ==============================================================
 
 /**
- * Check whether things are equal
+ * Check whether 'things' are equal
+ * Things are defined as any native types (string, number, boolean, null, date) and objects
+ * In the case of object, we check deep equality
  * Returns true if they are, false otherwise
  */
 function areThingsEqual (a, b) {
@@ -248,7 +250,8 @@ function areThingsEqual (a, b) {
   // undefined (no match since they mean field doesn't exist and can't be serialized)
   if (util.isArray(a) || util.isArray(b) || a === undefined || b === undefined) { return false; }
 
-  // a and b should be objects
+  // Objects (check for deep equality)
+  // a and b should be objects at this point
   try {
     aKeys = Object.keys(a);
     bKeys = Object.keys(b);
@@ -256,7 +259,6 @@ function areThingsEqual (a, b) {
     return false;
   }
 
-  // Objects
   if (aKeys.length !== bKeys.length) { return false; }
   for (i = 0; i < aKeys.length; i += 1) {
     if (bKeys.indexOf(aKeys[i]) === -1) { return false; }
@@ -279,7 +281,7 @@ function getDotValue (obj, field) {
   if (fieldParts.length === 1) {
     return obj[fieldParts[0]];
   } else {
-    return matcherFunctions.$eq(obj[fieldParts[0]], fieldParts.slice(1));
+    return getDotValue(obj[fieldParts[0]], fieldParts.slice(1));
   }
 }
 
@@ -291,19 +293,10 @@ function getDotValue (obj, field) {
  * @param {Model} value
  */
 matcherFunctions.$eq = function (obj, field, value) {
-  var fieldParts = typeof field === 'string' ? field.split('.') : field;
-
-  if (!obj) { return false; }   // field cannot be empty here so that means there is no match
-
-  if (fieldParts.length === 1) {
-    return areThingsEqual(obj[fieldParts[0]], value);
-  } else {
-    return matcherFunctions.$eq(obj[fieldParts[0]], fieldParts.slice(1), value);
-  }
+  return areThingsEqual(getDotValue(obj, field), value);
 };
 
 
-
 /**
  * Tell if a given document matches a query
  */
@@ -325,5 +318,6 @@ module.exports.deserialize = deserialize;
 module.exports.deepCopy = deepCopy;
 module.exports.checkObject = checkObject;
 module.exports.modify = modify;
+module.exports.getDotValue = getDotValue;
 module.exports.match = match;
 module.exports.areThingsEqual = areThingsEqual;

test/model.test.js

@@ -376,6 +376,22 @@ describe('Model', function () {
 
     });
 
+
+    describe('Getting a fields value in dot notation', function () {
+
+      it('Return first-level and nested values', function () {
+        model.getDotValue({ hello: 'world' }, 'hello').should.equal('world');
+        model.getDotValue({ hello: 'world', type: { planet: true, blue: true } }, 'type.planet').should.equal(true);
+      });
+
+      it('Return undefined if the field cannot be found in the object', function () {
+        assert.isUndefined(model.getDotValue({ hello: 'world' }, 'helloo'));
+        assert.isUndefined(model.getDotValue({ hello: 'world', type: { planet: true } }, 'type.plane'));
+      });
+
+    });
+
+
     describe('$eq', function () {
 
       it('Can find documents with simple fields', function () {