DataSourceVariables: Fix storing uninterpolated datasource in ds ref uid prop (#41248)

* DataSourceVariables: Fix storing uninterpolated datasource in ds ref uid prop

* better variable name

* Fix issue changing from data source variable to specific data source of the same type

* revert name change

* Update public/app/features/plugins/datasource_srv.ts

Co-authored-by: Ryan McKinley <ryantxu@gmail.com>

* Simply logic and remove deep clone

* updated comment

Co-authored-by: Ryan McKinley <ryantxu@gmail.com>

public/app/features/plugins/datasource_srv.ts

@@ -27,7 +27,6 @@ import {
   instanceSettings as expressionInstanceSettings,
 } from 'app/features/expressions/ExpressionDatasource';
 import { DataSourceVariableModel } from '../variables/types';
-import { cloneDeep } from 'lodash';
 
 export class DatasourceSrv implements DataSourceService {
   private datasources: Record<string, DataSourceApi> = {}; // UID
@@ -101,13 +100,14 @@ export class DatasourceSrv implements DataSourceService {
       if (!dsSettings) {
         return undefined;
       }
-      // The return name or uid needs preservet string containing the variable
-      const clone = cloneDeep(dsSettings);
-      clone.name = nameOrUid;
-      // A data source being looked up using a variable should not be considered default
-      clone.isDefault = false;
 
-      return clone;
+      // Return an instance with un-interpolated values for name and uid
+      return {
+        ...dsSettings,
+        isDefault: false,
+        name: nameOrUid,
+        uid: nameOrUid,
+      };
     }
 
     return this.settingsMapByUid[nameOrUid] ?? this.settingsMapByName[nameOrUid];
@@ -243,6 +243,7 @@ export class DatasourceSrv implements DataSourceService {
           base.push({
             ...dsSettings,
             name: key,
+            uid: key,
           });
         }
       }

public/app/features/plugins/specs/datasource_srv.test.ts

@@ -125,7 +125,7 @@ describe('datasource_srv', () => {
       it('should work with variable', () => {
         const ds = dataSourceSrv.getInstanceSettings('${datasource}');
         expect(ds?.name).toBe('${datasource}');
-        expect(ds?.uid).toBe('uid-code-BBB');
+        expect(ds?.uid).toBe('${datasource}');
       });
 
       it('should not set isDefault when being fetched via variable', () => {
@@ -136,7 +136,7 @@ describe('datasource_srv', () => {
       it('should work with variable', () => {
         const ds = dataSourceSrv.getInstanceSettings('${datasourceDefault}');
         expect(ds?.name).toBe('${datasourceDefault}');
-        expect(ds?.uid).toBe('uid-code-BBB');
+        expect(ds?.uid).toBe('${datasourceDefault}');
       });
     });