diff --git a/test/index.html b/test/index.html
index 954589083..4cb1e94fa 100644
--- a/test/index.html
+++ b/test/index.html
@@ -155,6 +155,7 @@
     <script src='spec/validations/crossing_ways.js'></script>
     <script src='spec/validations/disconnected_way.js'></script>
     <script src='spec/validations/generic_name.js'></script>
+    <script src='spec/validations/incompatible_source.js'></script>
     <script src='spec/validations/missing_role.js'></script>
     <script src='spec/validations/missing_tag.js'></script>
     <script src='spec/validations/old_multipolygon.js'></script>
diff --git a/test/spec/validations/incompatible_source.js b/test/spec/validations/incompatible_source.js
new file mode 100644
index 000000000..f8a3e2d90
--- /dev/null
+++ b/test/spec/validations/incompatible_source.js
@@ -0,0 +1,60 @@
+describe('iD.validations.incompatible_source', function () {
+    var context;
+
+    beforeEach(function() {
+        context = iD.coreContext();
+    });
+
+    function createWay(tags) {
+        var n1 = iD.osmNode({id: 'n-1', loc: [4,4]});
+        var n2 = iD.osmNode({id: 'n-2', loc: [4,5]});
+        var n3 = iD.osmNode({id: 'n-3', loc: [5,5]});
+        var w = iD.osmWay({id: 'w-1', nodes: ['n-1', 'n-2', 'n-3'], tags: tags});
+
+        context.perform(
+            iD.actionAddEntity(n1),
+            iD.actionAddEntity(n2),
+            iD.actionAddEntity(n3),
+            iD.actionAddEntity(w)
+        );
+    }
+
+    function validate() {
+        var validator = iD.validationIncompatibleSource();
+        var changes = context.history().changes();
+        var entities = changes.modified.concat(changes.created);
+        var issues = [];
+        entities.forEach(function(entity) {
+            issues = issues.concat(validator(entity, context));
+        });
+        return issues;
+    }
+
+    it('has no errors on init', function() {
+        var issues = validate();
+        expect(issues).to.have.lengthOf(0);
+    });
+
+    it('ignores way with no source tag', function() {
+        createWay({ amenity: 'cafe', building: 'yes', name: 'Key Largo Café'});
+        var issues = validate();
+        expect(issues).to.have.lengthOf(0);
+    });
+
+    it('ignores way with okay source tag', function() {
+        createWay({ amenity: 'cafe', building: 'yes', name: 'Key Largo Café', source: 'survey'});
+        var issues = validate();
+        expect(issues).to.have.lengthOf(0);
+    });
+
+    it('flags way with incompatible source tag', function() {
+        createWay({ amenity: 'cafe', building: 'yes', name: 'Key Largo Café', source: 'Google Maps'});
+        var issues = validate();
+        expect(issues).to.have.lengthOf(1);
+        var issue = issues[0];
+        expect(issue.type).to.eql('incompatible_source');
+        expect(issue.entities).to.have.lengthOf(1);
+        expect(issue.entities[0].id).to.eql('w-1');
+    });
+
+});