From 5f5ae50dc6f81ef2376f25960698322b00268e2e Mon Sep 17 00:00:00 2001
From: Justin Poehnelt <jpoehnelt@google.com>
Date: Tue, 2 Mar 2021 15:34:50 -0700
Subject: [PATCH] feat: add callback (#10)

---
 src/index.test.tsx | 20 ++++++++++++++++++++
 src/index.tsx      | 23 ++++++++++++++++++++---
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/src/index.test.tsx b/src/index.test.tsx
index 970cb994..2c911c62 100644
--- a/src/index.test.tsx
+++ b/src/index.test.tsx
@@ -138,3 +138,23 @@ test("it should pass props to Loader and use the correct script url", () => {
   // compare url to what is generated directly from loader
   expect(script.src).toBe(new Loader(loaderOptions).createUrl());
 });
+
+test("it should execute the callback", async () => {
+  const callback = jest.fn();
+  const loaderOptions: LoaderOptions = {
+    apiKey: "YOUR_API_KEY",
+  };
+
+  render(<Wrapper {...{...loaderOptions, callback}} />);
+
+  expect(callback.mock.calls[0][0]).toBe(Status.LOADING)
+  expect(callback.mock.calls[0][1]).toBeInstanceOf(Loader)
+
+  await executeLoaderCallback();
+
+  expect(callback.mock.calls[1][0]).toBe(Status.SUCCESS)
+  expect(callback.mock.calls[1][1]).toBeInstanceOf(Loader)
+
+  expect(callback).toBeCalledTimes(2)
+
+});
diff --git a/src/index.tsx b/src/index.tsx
index e39db82d..25763b81 100644
--- a/src/index.tsx
+++ b/src/index.tsx
@@ -32,6 +32,12 @@ export interface WrapperProps extends LoaderOptions {
    * Render prop used to switch on the status.
    */
   render?: (status: Status) => ReactElement;
+  /**
+   * Callback prop used to access `@googlemaps/js-api-loader` and `Status`.
+   *
+   * Note: The callback be executed multiple times in the lifecycle of the component.
+   */
+  callback?: (status: Status, loader: Loader) => void;
 }
 
 /**
@@ -52,15 +58,26 @@ export interface WrapperProps extends LoaderOptions {
 export const Wrapper = ({
   children,
   render,
+  callback,
   ...options
 }: WrapperProps): ReactElement => {
   const [status, setStatus] = useState(Status.LOADING);
 
   useEffect(() => {
-    new Loader(options).load().then(
-      () => setStatus(Status.SUCCESS),
-      () => setStatus(Status.FAILURE)
+    const loader = new Loader(options);
+
+    const setStatusAndExecuteCallback = (status: Status) => {
+      if (callback) callback(status, loader);
+      setStatus(status);
+    };
+
+    setStatusAndExecuteCallback(Status.LOADING);
+
+    loader.load().then(
+      () => setStatusAndExecuteCallback(Status.SUCCESS),
+      () => setStatusAndExecuteCallback(Status.FAILURE)
     );
+
   }, []);
 
   if (status === Status.SUCCESS && children) return <>{children}</>;