Use mergeContents instead of appending code to the end of file in withPodfile (#57)

* Use mergeContents instead of appending in withPodfile

* Add indents to merged podfile contents

Author: kowczarz

plugin/src/withPodfile.ts

@@ -1,3 +1,4 @@
+import { mergeContents } from "@expo/config-plugins/build/utils/generateCode";
 import { type ConfigPlugin, withDangerousMod } from "expo/config-plugins";
 import fs from "node:fs";
 import path from "node:path";
@@ -19,65 +20,68 @@ export const withPodfile: ConfigPlugin<{
 
       const useExpoModules =
         excludedPackages && excludedPackages.length > 0
-          ? `exclude = ["${excludedPackages.join(`", "`)}"]\n  use_expo_modules!(exclude: exclude)`
+          ? `exclude = ["${excludedPackages.join(`", "`)}"]\n    use_expo_modules!(exclude: exclude)`
           : "use_expo_modules!";
 
       const appClipTarget = `
-target '${targetName}' do
-  ${useExpoModules}
+  target '${targetName}' do
+    ${useExpoModules}
 
-  if ENV['EXPO_USE_COMMUNITY_AUTOLINKING'] == '1'
-    config_command = ['node', '-e', "process.argv=['', '', 'config'];require('@react-native-community/cli').run()"];
-  else
-    config_command = [
+    if ENV['EXPO_USE_COMMUNITY_AUTOLINKING'] == '1'
+      config_command = ['node', '-e', "process.argv=['', '', 'config'];require('@react-native-community/cli').run()"];
+    else
+      config_command = [
+        'node',
+        '--no-warnings',
+        '--eval',
+        'require(require.resolve(\\'expo-modules-autolinking\\', { paths: [require.resolve(\\'expo/package.json\\')] }))(process.argv.slice(1))',
+        'react-native-config',
+        '--json',
+        '--platform',
+        'ios'
+      ]
+    end
+
+    # Running the command in the same manner as \`use_react_native\` then running that result through our cliPlugin
+    json, message, status = Pod::Executable.capture_command(config_command[0], config_command[1..], capture: :both)
+    if not status.success?
+      Pod::UI.warn "The command: '#{config_command.join(" ").bold.yellow}' returned a status code of #{status.exitstatus.to_s.bold.red}, #{message}", [
+          "App Clip autolinking failed. Please ensure autolinking works correctly for the main app target and try again.",
+      ]
+      exit(status.exitstatus)
+    end
+
+    # \`react-native-app-clip\` resolves to react-native-app-clip/build/index.js
+    clip_command = [
       'node',
       '--no-warnings',
       '--eval',
-      'require(require.resolve(\\'expo-modules-autolinking\\', { paths: [require.resolve(\\'expo/package.json\\')] }))(process.argv.slice(1))',
-      'react-native-config',
-      '--json',
-      '--platform',
-      'ios'
-    ]
-  end
-
-  # Running the command in the same manner as \`use_react_native\` then running that result through our cliPlugin
-  json, message, status = Pod::Executable.capture_command(config_command[0], config_command[1..], capture: :both)
-  if not status.success?
-    Pod::UI.warn "The command: '#{config_command.join(" ").bold.yellow}' returned a status code of #{status.exitstatus.to_s.bold.red}, #{message}", [
-        "App Clip autolinking failed. Please ensure autolinking works correctly for the main app target and try again.",
+      'require(require.resolve(\\'react-native-app-clip\\')+\\'/../../plugin/build/cliPlugin.js\\').run(' + json + ', [${(excludedPackages ?? []).map((packageName) => `"${packageName}"`).join(", ")}])'
     ]
-    exit(status.exitstatus)
-  end
 
-  # \`react-native-app-clip\` resolves to react-native-app-clip/build/index.js
-  clip_command = [
-    'node',
-    '--no-warnings',
-    '--eval',
-    'require(require.resolve(\\'react-native-app-clip\\')+\\'/../../plugin/build/cliPlugin.js\\').run(' + json + ', [${(excludedPackages ?? []).map((packageName) => `"${packageName}"`).join(", ")}])'
-  ]
+    config = use_native_modules!(clip_command)
 
-  config = use_native_modules!(clip_command)
+    use_frameworks! :linkage => podfile_properties['ios.useFrameworks'].to_sym if podfile_properties['ios.useFrameworks']
+    use_frameworks! :linkage => ENV['USE_FRAMEWORKS'].to_sym if ENV['USE_FRAMEWORKS']
 
-  use_frameworks! :linkage => podfile_properties['ios.useFrameworks'].to_sym if podfile_properties['ios.useFrameworks']
-  use_frameworks! :linkage => ENV['USE_FRAMEWORKS'].to_sym if ENV['USE_FRAMEWORKS']
-
-  use_react_native!(
-    :path => config[:reactNativePath],
-    :hermes_enabled => podfile_properties['expo.jsEngine'] == nil || podfile_properties['expo.jsEngine'] == 'hermes',
-    # An absolute path to your application root.
-    :app_path => "#{Pod::Config.instance.installation_root}/..",
-    :privacy_file_aggregation_enabled => podfile_properties['apple.privacyManifestAggregationEnabled'] != 'false',
-  )
-end
-      `.trim();
+    use_react_native!(
+      :path => config[:reactNativePath],
+      :hermes_enabled => podfile_properties['expo.jsEngine'] == nil || podfile_properties['expo.jsEngine'] == 'hermes',
+      # An absolute path to your application root.
+      :app_path => "#{Pod::Config.instance.installation_root}/..",
+      :privacy_file_aggregation_enabled => podfile_properties['apple.privacyManifestAggregationEnabled'] != 'false',
+    )
+  end
+      `;
 
-      // It's generally safer to use `mergeContents` to insert new content into the Podfile, but this new target should always be inserted at the end of the file.
-      podfileContent = podfileContent
-        .concat(`\n\n# >>> Inserted by react-native-app-clip\n`)
-        .concat(appClipTarget)
-        .concat(`\n\n# <<< Inserted by react-native-app-clip\n`);
+      podfileContent = mergeContents({
+        tag: "Generated by react-native-app-clip",
+        src: podfileContent,
+        newSrc: appClipTarget,
+        anchor: "use_expo_modules!",
+        offset: 0,
+        comment: "#",
+      }).contents;
 
       fs.writeFileSync(podFilePath, podfileContent);