[strict[ ScreenCaptureButton

Summary: _typescript_

Reviewed By: jknoxville

Differential Revision: D17282357

fbshipit-source-id: 6ddd912978faa30195f59971f19d29d3ea79342b

src/chrome/ScreenCaptureButtons.tsx

@@ -119,8 +119,8 @@ class ScreenCaptureButtons extends Component<Props, State> {
       reportPlatformFailures(
         selectedDevice
           .screenshot()
-          .then((buffer: Buffer) => writeBufferToFile(pngPath, buffer))
-          .then((path: string) => openFile(path)),
+          .then(buffer => writeBufferToFile(pngPath, buffer))
+          .then(path => openFile(path)),
         'captureScreenshot',
       );
     }
@@ -206,13 +206,15 @@ class ScreenCaptureButtons extends Component<Props, State> {
     dst: string,
   ): Promise<string> => {
     return new Promise((resolve, reject) => {
-      return device.adb.pull(device.serial, src).then(stream => {
-        stream.on('end', () => {
-          resolve(dst);
+      return device.adb
+        .pull(device.serial, src)
+        .then((stream: NodeJS.ReadStream) => {
+          stream.on('end', () => {
+            resolve(dst);
+          });
+          stream.on('error', reject);
+          stream.pipe(fs.createWriteStream(dst));
         });
-        stream.on('error', reject);
-        stream.pipe(fs.createWriteStream(dst));
-      });
     });
   };
 
@@ -236,7 +238,7 @@ class ScreenCaptureButtons extends Component<Props, State> {
     return device.adb
       .shell(device.serial, command)
       .then(adb.util.readAll)
-      .then(output => output.toString().trim());
+      .then((output: Buffer) => output.toString().trim());
   };
 
   onRecordingClicked = () => {

src/utils/screenshot.tsx

@@ -11,7 +11,10 @@ import fs from 'fs';
  * Writes a buffer to a specified file path.
  * Returns a Promise which resolves to the file path.
  */
-export const writeBufferToFile = (filePath: string, buffer: Buffer) => {
+export const writeBufferToFile = (
+  filePath: string,
+  buffer: Buffer,
+): Promise<string> => {
   return new Promise((resolve, reject) => {
     fs.writeFile(filePath, buffer, err => {
       if (err) {