Added has and !has operators

Author: Lucas Wojciechowski

index.js

@@ -32,6 +32,8 @@ function compile(filter) {
         op === 'none' ? '!(' + filter.slice(1).map(compile).join('||') + ')' :
         op === 'in' ? compileIn(filter[1], filter.slice(2)) :
         op === '!in' ? '!(' + compileIn(filter[1], filter.slice(2)) + ')' :
+        op === 'has' ? compare(filter[1], undefined, '!==', false) :
+        op === '!has' ? compare(filter[1], undefined, '===', false) :
         'true';
     return '(' + str + ')';
 }

test.js

@@ -391,3 +391,29 @@ test('none', function(t) {
 
     t.end();
 });
+
+test('has', function(t) {
+    var f = filter(['has', 'foo']);
+    t.equal(f({properties: {foo: 0}}), true);
+    t.equal(f({properties: {foo: 1}}), true);
+    t.equal(f({properties: {foo: '0'}}), true);
+    t.equal(f({properties: {foo: true}}), true);
+    t.equal(f({properties: {foo: false}}), true);
+    t.equal(f({properties: {foo: null}}), true);
+    t.equal(f({properties: {foo: undefined}}), false);
+    t.equal(f({properties: {}}), false);
+    t.end();
+});
+
+test('!has', function(t) {
+    var f = filter(['!has', 'foo']);
+    t.equal(f({properties: {foo: 0}}), false);
+    t.equal(f({properties: {foo: 1}}), false);
+    t.equal(f({properties: {foo: '0'}}), false);
+    t.equal(f({properties: {foo: false}}), false);
+    t.equal(f({properties: {foo: false}}), false);
+    t.equal(f({properties: {foo: null}}), false);
+    t.equal(f({properties: {foo: undefined}}), true);
+    t.equal(f({properties: {}}), true);
+    t.end();
+});