fix: Preserve should not affect Form.List

examples/list.tsx

@@ -21,7 +21,10 @@ const Demo = () => {
           console.log('values:', values);
         }}
         style={{ border: '1px solid red', padding: 15 }}
+        preserve={false}
       >
+        <Form.Field shouldUpdate>{() => JSON.stringify(form.getFieldsValue(), null, 2)}</Form.Field>
+
         <List name="users">
           {(fields, { add, remove }) => {
             console.log('Demo Fields:', fields);

src/Field.tsx

@@ -73,13 +73,13 @@ export interface InternalFieldProps {
   initialValue?: any;
   onReset?: () => void;
   preserve?: boolean;
+
+  /** @private Passed by Form.List props. Do not use since it will break by path check. */
+  isListField?: boolean;
 }
 
 export interface FieldProps extends Omit<InternalFieldProps, 'name'> {
   name?: NamePath;
-
-  /** @private Passed by Form.List props. */
-  isListField?: boolean;
 }
 
 export interface FieldState {
@@ -102,7 +102,7 @@ class Field extends React.Component<InternalFieldProps, FieldState, InternalForm
     resetCount: 0,
   };
 
-  private cancelRegisterFunc: (preserve?: boolean) => void | null = null;
+  private cancelRegisterFunc: (isListField?: boolean, preserve?: boolean) => void | null = null;
 
   private destroy = false;
 
@@ -140,10 +140,10 @@ class Field extends React.Component<InternalFieldProps, FieldState, InternalForm
   }
 
   public cancelRegister = () => {
-    const { preserve } = this.props;
+    const { preserve, isListField } = this.props;
 
     if (this.cancelRegisterFunc) {
-      this.cancelRegisterFunc(preserve);
+      this.cancelRegisterFunc(isListField, preserve);
     }
     this.cancelRegisterFunc = null;
   };
@@ -498,13 +498,21 @@ class Field extends React.Component<InternalFieldProps, FieldState, InternalForm
   }
 }
 
-const WrapperField: React.FC<FieldProps> = ({ name, isListField, ...restProps }) => {
+const WrapperField: React.FC<FieldProps> = ({ name, ...restProps }) => {
   const namePath = name !== undefined ? getNamePath(name) : undefined;
 
   let key: string = 'keep';
-  if (!isListField) {
+  if (!restProps.isListField) {
     key = `_${(namePath || []).join('_')}`;
   }
+
+  if (process.env.NODE_ENV !== 'production') {
+    warning(
+      restProps.preserve !== false || !restProps.isListField,
+      '`preserve` should not apply on Form.List fields.',
+    );
+  }
+
   return <Field key={key} name={namePath} {...restProps} />;
 };
 

src/useForm.ts

@@ -493,12 +493,12 @@ export class FormStore {
     }
 
     // un-register field callback
-    return (preserve?: boolean) => {
+    return (isListField?: boolean, preserve?: boolean) => {
       this.fieldEntities = this.fieldEntities.filter(item => item !== entity);
 
       // Clean up store value if preserve
       const mergedPreserve = preserve !== undefined ? preserve : this.preserve;
-      if (mergedPreserve === false) {
+      if (mergedPreserve === false && !isListField) {
         const namePath = entity.getNamePath();
         if (this.getFieldValue(namePath) !== undefined) {
           this.store = setValue(this.store, namePath, undefined);

tests/preserve.test.tsx

@@ -1,7 +1,7 @@
-/* eslint-disable no-template-curly-in-string */
+/* eslint-disable no-template-curly-in-string, arrow-body-style */
 import React from 'react';
 import { mount } from 'enzyme';
-import Form from '../src';
+import Form, { FormInstance } from '../src';
 import InfoField from './common/InfoField';
 import timeout from './common/timeout';
 
@@ -74,5 +74,68 @@ describe('Form.Preserve', () => {
     await matchTest(true, { keep: 233 });
     await matchTest(false, { keep: 233, remove: 666 });
   });
+
+  it('form perishable should not crash Form.List', async () => {
+    let form: FormInstance;
+
+    const wrapper = mount(
+      <Form
+        initialValues={{ list: ['light', 'bamboo', 'little'] }}
+        preserve={false}
+        ref={instance => {
+          form = instance;
+        }}
+      >
+        <Form.List name="list">
+          {(fields, { remove }) => {
+            return (
+              <div>
+                {fields.map(field => (
+                  <Form.Field {...field}>
+                    <input />
+                  </Form.Field>
+                ))}
+                <button
+                  type="button"
+                  onClick={() => {
+                    remove(0);
+                  }}
+                />
+              </div>
+            );
+          }}
+        </Form.List>
+      </Form>,
+    );
+
+    wrapper.find('button').simulate('click');
+    wrapper.update();
+
+    expect(form.getFieldsValue()).toEqual({ list: ['bamboo', 'little'] });
+  });
+
+  it('warning when Form.List use preserve', () => {
+    const errorSpy = jest.spyOn(console, 'error').mockImplementation(() => {});
+
+    mount(
+      <Form initialValues={{ list: ['bamboo'] }}>
+        <Form.List name="list">
+          {fields =>
+            fields.map(field => (
+              <Form.Field {...field} preserve={false}>
+                <input />
+              </Form.Field>
+            ))
+          }
+        </Form.List>
+      </Form>,
+    );
+
+    expect(errorSpy).toHaveBeenCalledWith(
+      'Warning: `preserve` should not apply on Form.List fields.',
+    );
+
+    errorSpy.mockRestore();
+  });
 });
 /* eslint-enable no-template-curly-in-string */