Fixed moving of fields of different shapes (#31)

Author: erikras

src/move.js

@@ -59,9 +59,12 @@ const move: Mutator = (
     state.fields[destKey] = {
       ...source,
       name: destKey,
-      change: state.fields[destKey].change, // prevent functions from being overwritten
-      blur: state.fields[destKey].blur,
-      focus: state.fields[destKey].focus,
+      // prevent functions from being overwritten
+      // if the state.fields[destKey] does not exist, it will be created
+      // when that field gets registered, with its own change/blur/focus callbacks
+      change: state.fields[destKey] && state.fields[destKey].change,
+      blur: state.fields[destKey] && state.fields[destKey].blur,
+      focus: state.fields[destKey] && state.fields[destKey].focus,
       lastFieldState: undefined // clearing lastFieldState forces renotification
     }
   }

src/move.test.js

@@ -465,7 +465,7 @@ describe('move', () => {
       }
     }
     move(['foo', 0, 1], state, { changeValue })
-    expect(state).toEqual({
+    expect(state).toMatchObject({
       formState: {
         values: {
           foo: [{ dog: 'banana dog' }, { dog: 'apple dog', cat: 'apple cat' }]