Factorization of the modifiers

lib/model.js

@@ -214,91 +214,63 @@ function compareThings (a, b) {
 // Updating documents
 // ==============================================================
 
-
-lastStepModifierFunctions.$set = function (obj, field, value) {
-  obj[field] = value;
-};
-
-function findLastModificationStep (modifier, obj, field, value) {
-  var fieldParts = typeof field === 'string' ? field.split('.') : field;
-
-  if (fieldParts.length === 1) {
-    lastStepModifierFunctions[modifier](obj, field, value);
-  } else {
-    obj[fieldParts[0]] = obj[fieldParts[0]] || {};
-    modifierFunctions[modifier](obj[fieldParts[0]], fieldParts.slice(1), value);
-  }
-}
-
 /**
- * Set field to value in a model
- * Create it if it doesn't exist
- * @param {Object} obj The model to set a field for
+ * The signature of modifier functions is as follows
+ * Their structure is always the same: recursively follow the dot notation while creating
+ * the nested documents if needed, then apply the "last step modifier"
+ * @param {Object} obj The model to modify
  * @param {String} field Can contain dots, in that case that means we will set a subfield recursively
  * @param {Model} value
  */
-modifierFunctions.$set = function (obj, field, value) {
-  var fieldParts = typeof field === 'string' ? field.split('.') : field;
 
-  if (fieldParts.length === 1) {
-    obj[fieldParts[0]] = value;
-  } else {
-    obj[fieldParts[0]] = obj[fieldParts[0]] || {};
-    modifierFunctions.$set(obj[fieldParts[0]], fieldParts.slice(1), value);
-  }
+// Set a field to a new value
+lastStepModifierFunctions.$set = function (obj, field, value) {
+  obj[field] = value;
 };
 
+// Push an element to the end of an array field
+lastStepModifierFunctions.$push = function (obj, field, value) {
+  // Create the array if it doesn't exist
+  if (!obj.hasOwnProperty(field)) { obj[field] = []; }
 
-/**
- * Push an element at the last place of an array
- * @param {Object} obj The model to set a field for
- * @param {String} field Can contain dots, in that case that means we will set a subfield recursively
- * @param {Model} value
- */
-modifierFunctions.$push = function (obj, field, value) {
-  var fieldParts = typeof field === 'string' ? field.split('.') : field;
-
-  if (fieldParts.length === 1) {
-    // Create the array if it doesn't exist
-    if (!obj.hasOwnProperty(fieldParts[0])) { obj[fieldParts[0]] = []; }
-
-    if (!util.isArray(obj[fieldParts[0]])) { throw "Can't $push an element on non-array values"; }
-    obj[fieldParts[0]].push(value);
-  } else {
-    obj[fieldParts[0]] = obj[fieldParts[0]] || {};
-    modifierFunctions.$push(obj[fieldParts[0]], fieldParts.slice(1), value);
-  }
+  if (!util.isArray(obj[field])) { throw "Can't $push an element on non-array values"; }
+  obj[field].push(value);
 };
 
-
-/**
- * Increase (or decrease) a 'number' field
- * Create and initialize it if needed
- * @param {Object} obj The model to set a field for
- * @param {String} field Can contain dots, in that case that means we will set a subfield recursively
- * @param {Model} value
- */
-modifierFunctions.$inc = function (obj, field, value) {
-  var fieldParts = typeof field === 'string' ? field.split('.') : field;
-
+// Increment a numeric field's value
+lastStepModifierFunctions.$inc = function (obj, field, value) {
   if (typeof value !== 'number') { throw value + " must be a number"; }
 
-  if (fieldParts.length === 1) {
-    if (typeof obj[fieldParts[0]] !== 'number') {
-      if (!_.has(obj, fieldParts[0])) {
-        obj[fieldParts[0]] = value;
-      } else {
-        throw "Don't use the $inc modifier on non-number fields";
-      }
+  if (typeof obj[field] !== 'number') {
+    if (!_.has(obj, field)) {
+      obj[field] = value;
     } else {
-      obj[fieldParts[0]] += value;
+      throw "Don't use the $inc modifier on non-number fields";
     }
   } else {
-    obj[fieldParts[0]] = obj[fieldParts[0]] || {};
-    modifierFunctions.$inc(obj[fieldParts[0]], fieldParts.slice(1), value);
+    obj[field] += value;
   }
 };
 
+// Given its name, create the complete modifier function
+function createModifierFunction (modifier) {
+  return function (obj, field, value) {
+    var fieldParts = typeof field === 'string' ? field.split('.') : field;
+
+    if (fieldParts.length === 1) {
+      lastStepModifierFunctions[modifier](obj, field, value);
+    } else {
+      obj[fieldParts[0]] = obj[fieldParts[0]] || {};
+      modifierFunctions[modifier](obj[fieldParts[0]], fieldParts.slice(1), value);
+    }
+  };
+}
+
+// Actually create all modifier functions
+Object.keys(lastStepModifierFunctions).forEach(function (modifier) {
+  modifierFunctions[modifier] = createModifierFunction(modifier);
+});
+
 
 /**
  * Modify a DB object according to an update query

test/model.test.js

@@ -201,7 +201,7 @@ describe('Model', function () {
   });   // ==== End of 'Deep copying' ==== //
 
 
-  describe.only('Modifying documents', function () {
+  describe('Modifying documents', function () {
 
     it('Queries not containing any modifier just replace the document by the contents of the query but keep its _id', function () {
       var obj = { some: 'thing', _id: 'keepit' }