Allow ref objects to be passed (#308)

* Allow ref objects to be passed

* fix tests

* Added tests

.size-snapshot.json

@@ -1,25 +1,25 @@
 {
   "dist/index.umd.js": {
-    "bundled": 66802,
-    "minified": 23724,
-    "gzipped": 7169
+    "bundled": 67132,
+    "minified": 23802,
+    "gzipped": 7191
   },
   "dist/index.umd.min.js": {
-    "bundled": 31438,
-    "minified": 12846,
-    "gzipped": 4182
+    "bundled": 31768,
+    "minified": 12924,
+    "gzipped": 4205
   },
   "dist/index.esm.js": {
-    "bundled": 12271,
-    "minified": 7288,
-    "gzipped": 2066,
+    "bundled": 12577,
+    "minified": 7364,
+    "gzipped": 2096,
     "treeshaked": {
       "rollup": {
-        "code": 3754,
+        "code": 3832,
         "import_statements": 137
       },
       "webpack": {
-        "code": 4860
+        "code": 4938
       }
     }
   }

package.json

@@ -84,9 +84,9 @@
     "babel-jest": "^24.0.0",
     "cross-env": "^5.1.4",
     "emotion": "^9.1.1",
-    "enzyme": "^3.3.0",
-    "enzyme-adapter-react-16": "^1.1.1",
-    "enzyme-to-json": "^3.3.3",
+    "enzyme": "^3.10.0",
+    "enzyme-adapter-react-16": "^1.14.0",
+    "enzyme-to-json": "^3.4.0",
     "eslint": "^4.19.1",
     "eslint-config-prettier": "^2.9.0",
     "eslint-plugin-flowtype": "^2.46.1",

src/Popper.js

@@ -9,19 +9,19 @@ import PopperJS, {
 } from 'popper.js';
 import type { Style } from 'typed-styles';
 import { ManagerContext } from './Manager';
-import { safeInvoke, unwrapArray, shallowEqual } from './utils';
+import { unwrapArray, setRef, shallowEqual } from './utils';
+import { type Ref } from "./RefTypes";
 
-type getRefFn = (?HTMLElement) => void;
 type ReferenceElement = ReferenceObject | HTMLElement | null;
 type StyleOffsets = { top: number, left: number };
 type StylePosition = { position: 'absolute' | 'fixed' };
 
 export type PopperArrowProps = {
-  ref: getRefFn,
+  ref: Ref,
   style: StyleOffsets & Style,
 };
 export type PopperChildrenProps = {|
-  ref: getRefFn,
+  ref: Ref,
   style: StyleOffsets & StylePosition & Style,
   placement: Placement,
   outOfBoundaries: ?boolean,
@@ -33,7 +33,7 @@ export type PopperChildren = PopperChildrenProps => React.Node;
 export type PopperProps = {
   children: PopperChildren,
   eventsEnabled?: boolean,
-  innerRef?: getRefFn,
+  innerRef?: Ref,
   modifiers?: Modifiers,
   placement?: Placement,
   positionFixed?: boolean,
@@ -76,7 +76,7 @@ export class InnerPopper extends React.Component<PopperProps, PopperState> {
   setPopperNode = (popperNode: ?HTMLElement) => {
     if (!popperNode || this.popperNode === popperNode) return;
 
-    safeInvoke(this.props.innerRef, popperNode);
+    setRef(this.props.innerRef, popperNode);
     this.popperNode = popperNode;
 
     this.updatePopperInstance();
@@ -200,7 +200,7 @@ export class InnerPopper extends React.Component<PopperProps, PopperState> {
   }
 
   componentWillUnmount() {
-    safeInvoke(this.props.innerRef, null);
+    setRef(this.props.innerRef, null)
     this.destroyPopperInstance();
   }
 

src/Popper.test.js

@@ -86,6 +86,40 @@ describe('Popper component', () => {
     ).not.toThrow();
   });
 
+  it('accepts a ref function', () => {
+    const myRef = jest.fn();
+    const referenceElement = document.createElement('div');
+    mount(
+      <InnerPopper referenceElement={referenceElement} innerRef={myRef}>
+        {({ ref, style, placement}) => (
+          <div
+            ref={ref}
+            style={style}
+            data-placement={placement}
+          />
+        )}
+      </InnerPopper>
+    )
+    expect(myRef).toBeCalled();
+  });
+
+  it('accepts a ref object', () => {
+    const myRef = (React: any).createRef();
+    const referenceElement = document.createElement('div');
+    mount(
+      <InnerPopper referenceElement={referenceElement} innerRef={myRef}>
+        {({ ref, style, placement}) => (
+          <div
+            ref={ref}
+            style={style}
+            data-placement={placement}
+          />
+        )}
+      </InnerPopper>
+    )
+    expect(myRef.current).toBeDefined();
+  });
+
   it('accepts a `referenceElement` property', () => {
     class VirtualReference {
       getBoundingClientRect() {

src/RefTypes.js

@@ -0,0 +1,4 @@
+type RefHandler = (?HTMLElement) => void;
+type RefObject = { current?: HTMLElement};
+
+export type Ref = RefHandler | RefObject;

src/Reference.js

@@ -2,12 +2,13 @@
 import * as React from 'react';
 import warning from 'warning';
 import { ManagerContext } from './Manager';
-import { safeInvoke, unwrapArray } from './utils';
+import { safeInvoke, unwrapArray, setRef } from './utils';
+import { type Ref } from "./RefTypes";
 
-export type ReferenceChildrenProps = { ref: (?HTMLElement) => void };
+export type ReferenceChildrenProps = { ref: Ref };
 export type ReferenceProps = {
   children: ReferenceChildrenProps => React.Node,
-  innerRef?: (?HTMLElement) => void,
+  innerRef?: Ref,
 };
 
 type InnerReferenceProps = {
@@ -18,12 +19,12 @@ class InnerReference extends React.Component<
   ReferenceProps & InnerReferenceProps
 > {
   refHandler = (node: ?HTMLElement) => {
-    safeInvoke(this.props.innerRef, node);
+    setRef(this.props.innerRef, node)
     safeInvoke(this.props.setReferenceNode, node);
   };
 
   componentWillUnmount() {
-    safeInvoke(this.props.innerRef, null);
+    setRef(this.props.innerRef, null)
   }
 
   render() {

src/utils.js

@@ -1,5 +1,7 @@
 // @flow
 
+import { type Ref } from "./RefTypes";
+
 /**
  * Takes an argument and if it's an array, returns the first item in the array,
  * otherwise returns the argument. Used for Preact compatibility.
@@ -38,3 +40,17 @@ export const shallowEqual = (objA: { [key: string]: any}, objB: { [key: string]:
 
   return true;
 }
+
+/**
+ * Sets a ref using either a ref callback or a ref object
+ */
+export const setRef = (ref: ?Ref, node: ?HTMLElement) => {
+  // if its a function call it
+  if (typeof ref === "function") {
+    return safeInvoke(ref, node);
+  }
+  // otherwise we should treat it as a ref object
+  else if (ref != null) {
+    ref.current = node;
+  }
+}

typings/react-popper.d.ts

@@ -6,36 +6,37 @@ interface ManagerProps {
 }
 export class Manager extends React.Component<ManagerProps, {}> { }
 
-type RefHandler = (ref: HTMLElement | SVGElement | null) => void;
-
 interface ReferenceChildrenProps {
-  ref: RefHandler;
+  // React refs are supposed to be contravariant (allows a more general type to be passed rather than a more specific one)
+  // However, Typescript currently can't infer that fact for refs
+  // See https://github.com/microsoft/TypeScript/issues/30748 for more information
+  ref: React.Ref<any>;
 }
 
 interface ReferenceProps {
   children: (props: ReferenceChildrenProps) => React.ReactNode;
-  innerRef?: RefHandler;
+  innerRef?: React.Ref<any>;
 }
 export class Reference extends React.Component<ReferenceProps, {}> { }
 
 export interface PopperArrowProps {
-  ref: RefHandler;
+  ref: React.Ref<any>;
   style: React.CSSProperties;
 }
 
 export interface PopperChildrenProps {
   arrowProps: PopperArrowProps;
   outOfBoundaries: boolean | null;
   placement: PopperJS.Placement;
-  ref: RefHandler;
+  ref: React.Ref<any>;
   scheduleUpdate: () => void;
   style: React.CSSProperties;
 }
 
 export interface PopperProps {
   children: (props: PopperChildrenProps) => React.ReactNode;
   eventsEnabled?: boolean;
-  innerRef?: RefHandler;
+  innerRef?: React.Ref<any>;
   modifiers?: PopperJS.Modifiers;
   placement?: PopperJS.Placement;
   positionFixed?: boolean;