fix: copy public methods from component in HOC. fixes callstack#254

Author: satya164

src/core/withTheme.js

@@ -6,6 +6,31 @@ import merge from 'deepmerge';
 import ThemeProvider, { ThemeContext } from './ThemeProvider';
 import type { Theme } from '../types';
 
+const REACT_METHODS = [
+  'autobind',
+  'childContextTypes',
+  'componentDidMount',
+  'componentDidUpdate',
+  'componentWillMount',
+  'componentWillReceiveProps',
+  'componentWillUnmount',
+  'componentWillUpdate',
+  'contextTypes',
+  'displayName',
+  'getChildContext',
+  'getDefaultProps',
+  'getDOMNode',
+  'getInitialState',
+  'mixins',
+  'propTypes',
+  'render',
+  'replaceProps',
+  'setProps',
+  'shouldComponentUpdate',
+  'statics',
+  'updateComponent',
+];
+
 const isClassComponent = (Component: Function) => !!Component.prototype.render;
 
 export default function withTheme<Props: {}>(
@@ -81,17 +106,46 @@ export default function withTheme<Props: {}>(
         : this._root;
     };
 
-    // setNativeProps is used by Animated to set props on the native component
-    /* $FlowFixMe */
-    if (Comp.prototype.setNativeProps) {
-      // $FlowFixMe
-      ThemedComponent.prototype.setNativeProps = function setNativeProps(
-        ...args
-      ) {
-        const root = this.getWrappedInstance();
-        return root.setNativeProps(...args);
-      };
-    }
+    // Copy non-private methods and properties from underlying component
+    // This will take expose public methods and properties such as `focus`, `setNativeProps` etc.
+    // $FlowFixMe
+    Object.getOwnPropertyNames(Comp.prototype)
+      .filter(
+        prop =>
+          !(
+            REACT_METHODS.includes(prop) || // React specific methods and properties
+            prop in React.Component.prototype || // Properties from React's prototype such as `setState`
+            prop in ThemedComponent.prototype || // Properties from enhanced component's prototype
+            // Private methods
+            prop.startsWith('_')
+          )
+      )
+      .forEach(prop => {
+        // $FlowFixMe
+        if (typeof Comp.prototype[prop] === 'function') {
+          /* eslint-disable func-names */
+          // $FlowFixMe
+          ThemedComponent.prototype[prop] = function(...args) {
+            // Make sure the function is called with correct context
+            // $FlowFixMe
+            Comp.prototype[prop].apply(this.getWrappedInstance(), args);
+          };
+          // Set the function name for better debugging
+          // $FlowFixMe
+          ThemedComponent.prototype[prop].name = prop;
+        } else {
+          // Copy properties as getters and setters
+          // This make sure dynamic properties always stay up-to-date
+          Object.defineProperty(ThemedComponent.prototype, prop, {
+            get() {
+              return this.getWrappedInstance()[prop];
+            },
+            set(value) {
+              this.getWrappedInstance()[prop] = value;
+            },
+          });
+        }
+      });
   }
 
   hoistNonReactStatics(ThemedComponent, Comp);