Add Prometheus metricFindQuery unit tests

public/test/specs/prometheus-datasource-specs.js

 define([
   './helpers',
   'moment',
-  'app/plugins/datasource/prometheus/datasource',
-  'app/services/backendSrv',
-  'app/services/alertSrv'
+  'app/plugins/datasource/prometheus/datasource'
 ], function(helpers, moment) {
   'use strict';
 
@@ -11,7 +9,6 @@ define([
     var ctx = new helpers.ServiceTestContext();
 
     beforeEach(module('grafana.services'));
-    beforeEach(ctx.providePhase(['templateSrv']));
     beforeEach(ctx.createService('PrometheusDatasource'));
     beforeEach(function() {
       ctx.ds = new ctx.service({ url: '', user: 'test', password: 'mupp' });
@@ -56,6 +53,54 @@ define([
 
     });
 
+    describe('When performing metricFindQuery', function() {
+      var results;
+      var response;
+
+      it('label_values(resource) should generate label search query', function() {
+        response = {
+          status: "success",
+          data: ["value1", "value2", "value3"]
+        };
+        ctx.$httpBackend.expect('GET', '/api/v1/label/resource/values').respond(response);
+        ctx.ds.metricFindQuery('label_values(resource)').then(function(data) { results = data; });
+        ctx.$httpBackend.flush();
+        ctx.$rootScope.$apply();
+        expect(results.length).to.be(3);
+      });
+
+      it('label_values(metric, resource) should generate count metric query', function() {
+        response = {
+          status: "success",
+          data:{
+            resultType: "vector",
+            result:[
+              {metric:{resource:"value1"},value:[]},
+              {metric:{resource:"value2"},value:[]},
+              {metric:{resource:"value3"},value:[]}
+            ]
+          }
+        };
+        ctx.$httpBackend.expect('GET', /\/api\/v1\/query\?query=count\(metric\)%20by%20\(resource\)&time=.*/).respond(response);
+        ctx.ds.metricFindQuery('label_values(metric, resource)').then(function(data) { results = data; });
+        ctx.$httpBackend.flush();
+        ctx.$rootScope.$apply();
+        expect(results.length).to.be(3);
+      });
+
+      it('metrics(metric.*) should generate metric name query', function() {
+        response = {
+          status: "success",
+          data:["metric1","metric2","metric3","nomatch"]
+        };
+        ctx.$httpBackend.expect('GET', '/api/v1/label/__name__/values').respond(response);
+        ctx.ds.metricFindQuery('metrics(metric.*)').then(function(data) { results = data; });
+        ctx.$httpBackend.flush();
+        ctx.$rootScope.$apply();
+        expect(results.length).to.be(3);
+      });
+
+    });
   });
 });