Variables: Do not reset description on variable type change (#31933)

public/app/features/variables/state/sharedReducer.test.ts

@@ -6,6 +6,7 @@ import {
   addVariable,
   changeVariableOrder,
   changeVariableProp,
+  changeVariableType,
   duplicateVariable,
   removeVariable,
   setCurrentVariableValue,
@@ -16,7 +17,7 @@ import {
   variableStateNotStarted,
 } from './sharedReducer';
 import { ConstantVariableModel, QueryVariableModel, VariableHide, VariableOption } from '../types';
-import { ALL_VARIABLE_TEXT, ALL_VARIABLE_VALUE, toVariablePayload } from './types';
+import { ALL_VARIABLE_TEXT, ALL_VARIABLE_VALUE, toVariablePayload, VariableIdentifier } from './types';
 import { variableAdapters } from '../adapters';
 import { createQueryVariableAdapter } from '../query/adapter';
 import { initialQueryVariableModelState } from '../query/reducer';
@@ -489,4 +490,36 @@ describe('sharedReducer', () => {
         });
     });
   });
+
+  describe('when changeVariableType is dispatched', () => {
+    it('then state should be correct', () => {
+      const queryAdapter = createQueryVariableAdapter();
+      const { initialState: queryAdapterState } = getVariableTestContext(queryAdapter);
+      const constantAdapter = createConstantVariableAdapter();
+      const { initialState: constantAdapterState } = getVariableTestContext(constantAdapter);
+      const newType = 'constant' as VariableType;
+      const identifier: VariableIdentifier = { id: '0', type: 'query' };
+      const payload = toVariablePayload(identifier, { newType });
+      reducerTester<VariablesState>()
+        .givenReducer(sharedReducer, cloneDeep(queryAdapterState))
+        .whenActionIsDispatched(changeVariableNameSucceeded(toVariablePayload(identifier, { newName: 'test' })))
+        .whenActionIsDispatched(
+          changeVariableProp(toVariablePayload(identifier, { propName: 'description', propValue: 'new description' }))
+        )
+        .whenActionIsDispatched(
+          changeVariableProp(toVariablePayload(identifier, { propName: 'label', propValue: 'new label' }))
+        )
+        .whenActionIsDispatched(changeVariableType(payload))
+        .thenStateShouldEqual({
+          ...constantAdapterState,
+          '0': {
+            ...constantAdapterState[0],
+            name: 'test',
+            description: 'new description',
+            label: 'new label',
+            type: 'constant',
+          },
+        });
+    });
+  });
 });

public/app/features/variables/state/sharedReducer.ts

@@ -101,7 +101,7 @@ const sharedReducerSlice = createSlice({
     },
     changeVariableType: (state: VariablesState, action: PayloadAction<VariablePayload<{ newType: VariableType }>>) => {
       const { id } = action.payload;
-      const { label, name, index } = state[id];
+      const { label, name, index, description } = state[id];
 
       state[id] = {
         ...cloneDeep(variableAdapters.get(action.payload.data.newType).initialState),
@@ -109,6 +109,7 @@ const sharedReducerSlice = createSlice({
         label,
         name,
         index,
+        description,
       };
     },
     setCurrentVariableValue: (

public/test/core/redux/reducerTester.ts

@@ -18,6 +18,7 @@ export interface When<State> {
 export interface Then<State> {
   thenStateShouldEqual: (state: State) => When<State>;
   thenStatePredicateShouldEqual: (predicate: (resultingState: State) => boolean) => When<State>;
+  whenActionIsDispatched: (action: PayloadAction<any> | Action<any>) => Then<State>;
 }
 
 interface ObjectType extends Object {