fix(android): config plugin build flag module override

src/config-plugin/index.ts

@@ -1,10 +1,12 @@
 import {
   ConfigPlugin,
   createRunOncePlugin,
+  Mod,
   withAndroidManifest,
   withDangerousMod,
   withInfoPlist,
 } from "@expo/config-plugins";
+import { ExpoConfig } from "@expo/config-types";
 import { generateOverrides, resolveFlagsToInvert } from "../api";
 import pkg from "../../package.json";
 import { withFlaggedAutolinking } from "./withFlaggedAutolinking";
@@ -49,25 +51,57 @@ const withAppleBuildFlags: ConfigPlugin<{ flags: string[] }> = (
   });
 };
 
-const withBundleFlags: ConfigPlugin<{ flags: string[] }> = (config, props) => {
+type BundlePluginProps = { flags: string[] };
+
+const createCrossPlatformMod =
+  ({
+    config,
+    props,
+  }: {
+    config: ExpoConfig;
+    props: BundlePluginProps;
+  }): Mod<unknown> =>
+  async (modConfig) => {
+    const { flags } = props;
+    let flagsToEnable = new Set(flags);
+    const invertable = await resolveFlagsToInvert(config);
+    if (invertable.flagsToEnable.size > 0) {
+      flagsToEnable = mergeSets(flagsToEnable, invertable.flagsToEnable);
+    }
+    await generateOverrides({
+      flagsToEnable,
+      flagsToDisable: invertable.flagsToDisable,
+    });
+    return modConfig;
+  };
+
+const withAndroidBundleBuildFlags: ConfigPlugin<BundlePluginProps> = (
+  config,
+  props
+) => {
   return withDangerousMod(config, [
-    "ios", // not platform-specific, but need to specify
-    async (modConfig) => {
-      const { flags } = props;
-      let flagsToEnable = new Set(flags);
-      const invertable = await resolveFlagsToInvert(config);
-      if (invertable.flagsToEnable.size > 0) {
-        flagsToEnable = mergeSets(flagsToEnable, invertable.flagsToEnable);
-      }
-      await generateOverrides({
-        flagsToEnable,
-        flagsToDisable: invertable.flagsToDisable,
-      });
-      return modConfig;
-    },
+    "android",
+    createCrossPlatformMod({ config, props }),
   ]);
 };
 
+const withAppleBundleBuildFlags: ConfigPlugin<BundlePluginProps> = (
+  config,
+  props
+) => {
+  return withDangerousMod(config, [
+    "ios",
+    createCrossPlatformMod({ config, props }),
+  ]);
+};
+
+const withBundleFlags: ConfigPlugin<{ flags: string[] }> = (config, props) => {
+  return withAppleBundleBuildFlags(
+    withAndroidBundleBuildFlags(config, props),
+    props
+  );
+};
+
 const parseEnvFlags = () => {
   const envFlags = process.env.EXPO_BUILD_FLAGS;
   if (!envFlags) {

test/overrides/default-flags.yml

@@ -1,5 +1,9 @@
 mergePath: "constants/buildFlags.ts"
 flags:
+  secretAndroidFeature:
+    value: false
+    meta:
+      team: "platform"
   secretFeature:
     value: false
     meta:

test/overrides/expected-api-override.ts

@@ -1,5 +1,6 @@
 export const BuildFlags = {
     newFeature: true,
     publishedFeatured: true,
+    secretAndroidFeature: false,
     secretFeature: false
 };

test/overrides/expected-cli-override.ts

@@ -1,5 +1,6 @@
 export const BuildFlags = {
     newFeature: false,
     publishedFeatured: true,
+    secretAndroidFeature: false,
     secretFeature: true
 };

test/run-integration.sh

@@ -1,13 +1,18 @@
 #!/bin/bash
 
+#
+# WARNING - these tests build on top of each other
+# adjust your initial test flag state accordingly
+#
+
 set -e
 
-function logMark () {
-  echo ""
-  echo "###################################################################"
-  echo "$1"
-  echo "###################################################################"
-  echo ""
+function logMark() {
+	echo ""
+	echo "###################################################################"
+	echo "$1"
+	echo "###################################################################"
+	echo ""
 }
 
 logMark "Setting up test environment"
@@ -24,5 +29,8 @@ node ../test/test-babel-plugin.js
 logMark "Running test-config-plugin.js"
 node ../test/test-config-plugin.js
 
+logMark "Running test-config-plugin-android.js"
+node ../test/test-config-plugin-android.js
+
 logMark "Running test-autolinking.js"
 node ../test/test-autolinking.js

test/test-config-plugin-android.js

@@ -0,0 +1,70 @@
+const fs = require("fs");
+const cp = require("child_process");
+const yaml = require("yaml");
+
+const expectedRuntimeModule = `
+export const BuildFlags = {
+    bundleIdScopedFeature: true,
+    newFeature: true,
+    publishedFeatured: true,
+    secretAndroidFeature: true,
+    secretFeature: false
+};
+`;
+
+addBundleIdScopedFlag();
+installExpoConfigPlugin();
+runPrebuild();
+assertFlagsAllTrue();
+
+function addBundleIdScopedFlag() {
+  const flagsYmlString = fs.readFileSync("flags.yml", { encoding: "utf-8" });
+  const flagConfig = yaml.parse(flagsYmlString);
+  flagConfig.flags.bundleIdScopedFeature = {
+    value: false,
+    invertFor: {
+      bundleId: ["com.example.app"],
+    },
+  };
+  fs.writeFileSync("flags.yml", yaml.stringify(flagConfig));
+}
+
+function installExpoConfigPlugin() {
+  const expoConfig = JSON.parse(fs.readFileSync("app.json", "utf-8"));
+  expoConfig.expo.plugins.push("expo-build-flags");
+  expoConfig.expo.ios.bundleIdentifier = "com.example.app";
+  expoConfig.expo.android.package = "com.example.app";
+  fs.writeFileSync("app.json", JSON.stringify(expoConfig, null, 2));
+}
+
+function runPrebuild() {
+  cp.execSync("./node_modules/.bin/expo prebuild -p android --clean", {
+    env: {
+      ...process.env,
+      CI: 1,
+      EXPO_BUILD_FLAGS: "secretAndroidFeature",
+    },
+  });
+}
+
+function assertFlagsAllTrue() {
+  const fileContents = fs.readFileSync("constants/buildFlags.ts", "utf8");
+  if (fileContents.trim() !== expectedRuntimeModule.trim()) {
+    console.log(
+      "received:\n\n",
+      `>${fileContents.trim()}<`,
+      "\n\n",
+      "expected:\n\n",
+      `>${expectedRuntimeModule.trim()}<`,
+      "\n\n"
+    );
+
+    throw new Error(
+      "Expected runtime buildFlags.ts module to contain all flags as true"
+    );
+  }
+
+  console.log(
+    "Assertion passed: Runtime build flags enabled by config plugin!"
+  );
+}

test/test-config-plugin.js

@@ -7,6 +7,7 @@ export const BuildFlags = {
     bundleIdScopedFeature: true,
     newFeature: true,
     publishedFeatured: true,
+    secretAndroidFeature: false,
     secretFeature: true
 };
 `;