diff --git a/src/store/data-source/reducer.js b/src/store/data-source/reducer.js
index 29ccbca..b9d39e8 100644
--- a/src/store/data-source/reducer.js
+++ b/src/store/data-source/reducer.js
@@ -21,26 +21,30 @@ export default function dataSources(state=[], action) {
     case fulfilled(SYNC_DATA_SOURCES):
       persistSavedDataSources(action.payload)
       return action.payload
-    case SAVE_DATA_SOURCE:
-      let dataSources = state.map((dataSource, index) => (index === action.index ? {...action.payload, unsaved: false} : dataSource));
+    case SAVE_DATA_SOURCE: {
+      const dataSources = state.map((dataSource, index) => (index === action.index ? {...action.payload, unsaved: false} : dataSource))
       persistSavedDataSources(dataSources)
       return dataSources
-    case DELETE_DATA_SOURCE:
-      dataSources = [...state]
+    }
+    case DELETE_DATA_SOURCE: {
+      const dataSources = [...state]
       dataSources[action.index].deleted = true
       persistSavedDataSources(dataSources)
       return dataSources
+    }
     case MODIFY_DATA_SOURCE_NAME:
     case MODIFY_DATA_SOURCE_ICON:
-    case ENABLE_DATA_SOURCE:
-      dataSources = state.map((dataSource, index) => (index === action.index ? {...action.payload} : dataSource));
+    case ENABLE_DATA_SOURCE: {
+      const dataSources = state.map((dataSource, index) => (index === action.index ? {...action.payload} : dataSource))
       persistSavedDataSources(dataSources)
       return dataSources
+    }
     case MODIFY_DATA_SOURCE_URL:
-    case MODIFY_DATA_SOURCE_ENERGY_PRD_URL:
-      dataSources = state.map((dataSource, index) => (index === action.index ? {...action.payload, unsaved: true} : dataSource))
+    case MODIFY_DATA_SOURCE_ENERGY_PRD_URL: {
+      const dataSources = state.map((dataSource, index) => (index === action.index ? {...action.payload, unsaved: true} : dataSource))
       persistSavedDataSources(dataSources)
       return dataSources
+    }
     default:
       return state
   }