fix: Supporting post install script on Windows (#12)

apps/example-app/package.json

@@ -7,7 +7,7 @@
     "@babel/plugin-transform-react-jsx": "^7.14.9",
     "@capacitor/android": "^4.7.3",
     "@capacitor/app": "4.0.1",
-    "@capacitor/background-runner": "^4.0.0-rc.1",
+    "@capacitor/background-runner": "^1.0.0-rc.1",
     "@capacitor/core": "^4.7.3",
     "@capacitor/haptics": "4.1.0",
     "@capacitor/ios": "^4.7.3",

packages/capacitor-plugin/package.json

@@ -11,6 +11,7 @@
     "android/build.gradle",
     "dist/",
     "ios/Plugin/",
+    "scripts/install_libs.js",
     "CapacitorBackgroundRunner.podspec"
   ],
   "author": "Ionic Team",
@@ -43,7 +44,7 @@
     "clean": "rimraf ./dist",
     "watch": "tsc --watch",
     "prepublishOnly": "npm run build",
-    "postinstall": "mkdir -p $INIT_CWD/android/app/libs/ && cp -f android/src/main/libs/android-js-engine-release.aar $INIT_CWD/android/app/libs/"
+    "postinstall": "node ./scripts/install_libs.js"
   },
   "devDependencies": {
     "@capacitor/android": "^5.2.1",

packages/capacitor-plugin/scripts/install_libs.js

@@ -0,0 +1,30 @@
+const fs = require('fs');
+const path = require('path');
+
+let workingDir = process.env.INIT_CWD;
+if (!workingDir) {
+  workingDir = '.';
+}
+
+if (!fs.existsSync(path.join(workingDir, 'android'))) {
+  console.warn(
+    'cannot install android-js-engine library: @capacitor/android not installed, or in wrong parent directory.',
+  );
+  return;
+}
+
+const releaseAARPath = path.join(
+  'android/src/main/libs/android-js-engine-release.aar',
+);
+
+const fullPath = path.join(workingDir, 'android/app/libs');
+if (!fs.existsSync(fullPath)) {
+  fs.mkdirSync(fullPath);
+}
+
+fs.copyFileSync(
+  releaseAARPath,
+  path.join(fullPath, 'android-js-engine-release.aar'),
+);
+
+console.log(`copied android-js-engine-release.aar to ${fullPath}`);