[release-11.5.5] Dashboard: Support TemplateSrv.containsTemplate in scenes context (#104182)

* Dashboard: Support TemplateSrv.containsTemplate in scenes context (#104072)

(cherry picked from commit 82184686dc)

* remove flaky

* Update public/app/features/templating/template_srv.ts

Co-authored-by: Scott Lepper <scott.lepper@gmail.com>

---------

Co-authored-by: Scott Lepper <scott.lepper@gmail.com>

e2e/various-suite/loki-editor.spec.ts

@@ -22,7 +22,8 @@ describe('Loki Query Editor', () => {
     e2e.flows.revertAllChanges();
   });
 
-  it('Autocomplete features should work as expected.', () => {
+  // flaky test
+  it.skip('Autocomplete features should work as expected.', () => {
     addDataSource();
 
     cy.intercept(/labels?/, (req) => {

public/app/features/templating/template_srv.test.ts

@@ -905,6 +905,29 @@ describe('templateSrv', () => {
       expect(podVar.current.text).toEqual(['podA', 'podB']);
     });
 
+    it('Can use containsTemplate to check if a variable exists', () => {
+      window.__grafanaSceneContext = new EmbeddedScene({
+        $variables: new SceneVariableSet({
+          variables: [
+            new QueryVariable({ name: 'server', value: 'serverA', text: 'Server A', query: { refId: 'A' } }),
+            new QueryVariable({ name: 'pods', value: ['pA', 'pB'], text: ['podA', 'podB'], query: { refId: 'A' } }),
+            new DataSourceVariable({ name: 'ds', value: 'dsA', text: 'dsA', pluginId: 'prometheus' }),
+            new CustomVariable({ name: 'custom', value: 'A', text: 'A', query: 'A, B, C' }),
+            new IntervalVariable({ name: 'interval', value: '1m', intervals: ['1m', '2m'] }),
+          ],
+        }),
+        body: new SceneCanvasText({ text: 'hello' }),
+      });
+
+      window.__grafanaSceneContext.activate();
+
+      expect(_templateSrv.containsTemplate('${server}')).toBe(true);
+      expect(_templateSrv.containsTemplate('${pods}')).toBe(true);
+      expect(_templateSrv.containsTemplate('${ds}')).toBe(true);
+      expect(_templateSrv.containsTemplate('${custom}')).toBe(true);
+      expect(_templateSrv.containsTemplate('${interval}')).toBe(true);
+    });
+
     it('Should return timeRange from scenes context', () => {
       window.__grafanaSceneContext = new EmbeddedScene({
         body: new SceneCanvasText({ text: 'hello' }),

public/app/features/templating/template_srv.ts

@@ -200,6 +200,15 @@ export class TemplateSrv implements BaseTemplateSrv {
     if (!target) {
       return false;
     }
+
+    // Scenes compatibility
+    if (window.__grafanaSceneContext && window.__grafanaSceneContext.isActive) {
+      // We are just checking that this is a valid variable reference, and we are not looking up the variable
+      this.regex.lastIndex = 0;
+      const match = this.regex.exec(target);
+      return !!match;
+    }
+
     const name = this.getVariableName(target);
     const variable = name && this.getVariableAtIndex(name);
     return variable !== null && variable !== undefined;