Send the binary hash in update_check on Android too

CodePush.js

@@ -1,8 +1,9 @@
 import { AcquisitionManager as Sdk, DownloadStatus } from "./lib/commonjs/acquisition-sdk/acquisition-sdk";
+import { buildQueryPackage } from "./lib/commonjs/build-query-package";
 import { onceUntilRejected } from "./lib/commonjs/once-until-rejected";
 import { Alert } from "./AlertAdapter";
 import requestFetchAdapter from "./request-fetch-adapter";
-import { AppState, NativeEventEmitter, Platform } from "react-native";
+import { AppState, NativeEventEmitter } from "react-native";
 import log, { logFields, packageLogFields, redactUrl } from "./logging";
 import hoistStatics from 'hoist-non-react-statics';
 
@@ -111,15 +112,7 @@ async function checkForUpdate(deploymentKey = null, handleBinaryVersionMismatchC
    * to send the app version to the server, since we are interested
    * in any updates for current binary version, regardless of hash.
    */
-  let queryPackage;
-  if (localPackage) {
-    queryPackage = localPackage;
-  } else {
-    queryPackage = { appVersion: config.appVersion };
-    if (Platform.OS === "ios" && config.packageHash) {
-      queryPackage.packageHash = config.packageHash;
-    }
-  }
+  const queryPackage = buildQueryPackage(localPackage, config);
 
   log.info(`Checking for update. ${logFields({ appVersion: queryPackage.appVersion, ...packageLogFields(queryPackage), deploymentKey: config.deploymentKey })}`);
   const update = await sdk.queryUpdateWithCurrentPackage(queryPackage);
@@ -137,10 +130,8 @@ async function checkForUpdate(deploymentKey = null, handleBinaryVersionMismatchC
    *    bug in the server, but we're adding this check just to double-check that the
    *    client app is resilient to a potential issue with the update check.
    * 4) The server said there is an update, but the update's hash is the same as that
-   *    of the binary's currently running version. This should only happen in Android -
-   *    unlike iOS, we don't attach the binary's hash to the updateCheck request
-   *    because we want to avoid having to install diff updates against the binary's
-   *    version, which we can't do yet on Android.
+   *    of the binary's currently running version. The binary's hash is sent in the
+   *    updateCheck request, so the server can answer with the binary itself.
    */
   if (!update) {
     log.info("No update available.");

src/__tests__/build-query-package.test.ts

@@ -0,0 +1,24 @@
+import * as assert from 'assert';
+
+import { buildQueryPackage } from '../build-query-package';
+
+describe('buildQueryPackage', () => {
+  it('sends the binary hash when no update is installed', () => {
+    assert.deepStrictEqual(buildQueryPackage(null, { appVersion: '1.0.0', packageHash: 'abc' }), {
+      appVersion: '1.0.0',
+      packageHash: 'abc',
+    });
+  });
+
+  it('omits the hash when the binary has none', () => {
+    assert.deepStrictEqual(buildQueryPackage(undefined, { appVersion: '1.0.0', packageHash: null }), {
+      appVersion: '1.0.0',
+    });
+    assert.deepStrictEqual(buildQueryPackage(undefined, { appVersion: '1.0.0' }), { appVersion: '1.0.0' });
+  });
+
+  it('uses the installed package as is', () => {
+    const localPackage = { appVersion: '1.0.0', packageHash: 'installed' };
+    assert.strictEqual(buildQueryPackage(localPackage, { appVersion: '1.0.0', packageHash: 'abc' }), localPackage);
+  });
+});

src/build-query-package.ts

@@ -0,0 +1,20 @@
+export interface QueryPackage {
+  appVersion?: string;
+  packageHash?: string;
+  [key: string]: unknown;
+}
+
+export function buildQueryPackage(
+  localPackage: QueryPackage | null | undefined,
+  config: { appVersion: string; packageHash?: string | null },
+): QueryPackage {
+  if (localPackage) {
+    return localPackage;
+  }
+  const queryPackage: QueryPackage = { appVersion: config.appVersion };
+  // Null in Android debug builds, which have no binary hash to report.
+  if (config.packageHash) {
+    queryPackage.packageHash = config.packageHash;
+  }
+  return queryPackage;
+}