Add neq operator (#55)

README.md

@@ -146,7 +146,7 @@ A filter parameter has the following format:
 A `propertyReference` is either simply a property name like `firstName` or a reference to a relation's property like
 `children.age` (`children` is the name of the relation).
 
-`filter` is one of the built-in filters `eq`, `lt`, `lte`, `gt`, `gte`, `like`, `likeLower` `in`, `notNull` or `isNull`.
+`filter` is one of the built-in filters `eq`, `neq`, `lt`, `lte`, `gt`, `gte`, `like`, `likeLower` `in`, `notNull` or `isNull`.
 Filter can also be a custom filter registered using the `registerFilter` method.
 
 The following examples explain how filter parameters work. For the examples, assume we have an objection.js model

lib/filters.js

@@ -3,6 +3,7 @@
 module.exports = {
   in: inSet,
   eq: eq,
+  neq: neq,
   lt: lt,
   lte: lte,
   gt: gt,
@@ -40,6 +41,13 @@ function eq(propertyRef, value) {
   return basicWhere(propertyRef, '=', value);
 }
 
+/**
+ * @private
+ */
+function neq(propertyRef, value) {
+  return basicWhere(propertyRef, '<>', value);
+}
+
 /**
  * @private
  */

tests/test.js

@@ -85,6 +85,29 @@ describe('integration tests', () => {
           });
         });
 
+        describe('neq', () => {
+          it('should filter using <> operator', () => {
+            return objectionFind(Person)
+              .build({
+                'firstName:neq': 'F01'
+              })
+              .then(results => {
+                // Everything except 'F01'
+                expect(results.map(result => result.firstName).sort()).to.eql([
+                  'F00',
+                  'F02',
+                  'F03',
+                  'F04',
+                  'F05',
+                  'F06',
+                  'F07',
+                  'F08',
+                  'F09'
+                ]);
+              });
+          })
+        });
+
         describe('lt', function() {
           it('should filter using < operator', function() {
             return objectionFind(Person)