Added 'to contain no elements matching' assertion

Munter · Munter · commit 6ef1b713398a · 2015-05-11T18:08:29.000+02:00
diff --git a/lib/index.js b/lib/index.js
@@ -715,6 +715,10 @@ module.exports = {
       return this.shift(expect, queryResult, 1);
     });
 
+    expect.addAssertion(['DOMDocument', 'DOMElement'], 'to contain no elements matching', function (expect, subject, value) {
+      return expect(subject.querySelectorAll(value), 'to satisfy', []);
+    });
+
     expect.addAssertion('string', 'when parsed as (html|HTML)', function (expect, subject) {
       this.errorMode = 'nested';
       var htmlDocument;
diff --git a/test/unexpected-dom.js b/test/unexpected-dom.js
@@ -834,6 +834,41 @@ describe('unexpected-dom', function () {
     });
   });
 
+  describe('to contain no elements matching', function () {
+    it('should pass when not matching anything', function () {
+      var document = jsdom.jsdom('<!DOCTYPE html><html><body></body></html>');
+
+      expect(document, 'to contain no elements matching', '.foo');
+    });
+
+    it('should fail when matching a single node', function () {
+      var document = jsdom.jsdom('<!DOCTYPE html><html><body><div class="foo"></div></body></html>');
+
+      expect(function () {
+        expect(document, 'to contain no elements matching', '.foo');
+      }, 'to throw', 'expected <!DOCTYPE html><html><head></head><body>...</body></html> to contain no elements matching \'.foo\'\n' +
+          '\n' +
+          '[\n' +
+          '  <div class="foo"></div> // should be removed\n' +
+          ']'
+      );
+    });
+
+    it('should fail when matching a NodeList', function () {
+      var document = jsdom.jsdom('<!DOCTYPE html><html><body><div class="foo"></div><div class="foo"></div></body></html>');
+
+      expect(function () {
+        expect(document, 'to contain no elements matching', '.foo');
+      }, 'to throw', 'expected <!DOCTYPE html><html><head></head><body>......</body></html> to contain no elements matching \'.foo\'\n' +
+          '\n' +
+          '[\n' +
+          '  <div class="foo"></div>, // should be removed\n' +
+          '  <div class="foo"></div> // should be removed\n' +
+          ']'
+      );
+    });
+  });
+
   describe('diffing', function () {
     function parseHtmlElement(str) {
       return jsdom.jsdom('<!DOCTYPE html><html><body>' + str + '</body></html>').body.firstChild;
