fix(config): ConfigContext 默认值应该为空对象，以便子元素获取对象中的配置

__tests__/index.js

@@ -1,5 +1,5 @@
-import {ConfigProvider, useConfig} from '../index';
-import {render} from '@testing-library/react';
+import { ConfigProvider, useConfig } from '../index';
+import { render } from '@testing-library/react';
 
 describe('config', () => {
   test('basic', () => {
@@ -8,11 +8,21 @@ describe('config', () => {
       return config.key;
     };
 
-    const {container} = render(<ConfigProvider config={{
+    const { container } = render(<ConfigProvider config={{
       key: 'value',
     }}>
       <Child/>
     </ConfigProvider>);
     expect(container).toMatchSnapshot();
   });
+
+  test('default value is {}', () => {
+    const Main = () => {
+      const config = useConfig();
+      return Object.keys(config).length;
+    };
+
+    const { container } = render(<Main/>);
+    expect(container.innerHTML).toBe('0');
+  });
 });

index.js

@@ -1,7 +1,7 @@
 import { createContext, useContext, useEffect, useState } from 'react';
 import propTypes from 'prop-types';
 
-const ConfigContext = createContext(null);
+const ConfigContext = createContext({});
 
 const ConfigProvider = ({config: userConfig = {}, children}) => {
   const [config, setConfig] = useState(userConfig);