fix(ios): use post_install hook for OnsideKit visibility instead of subspec

OnsideKit is not on CocoaPods CDN yet, so subspec dependency fails to
resolve. Instead, inject a post_install hook that adds OnsideKit's build
dir to ExpoIap's SWIFT_INCLUDE_PATHS, making #if canImport(OnsideKit)
work without requiring a podspec dependency.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: hyochan

ios/ExpoIap.podspec

@@ -26,11 +26,9 @@ Pod::Spec.new do |s|
   s.dependency 'ExpoModulesCore'
   s.dependency 'openiap', "#{versions['apple']}"
 
-  s.subspec 'Onside' do |ss|
-    ss.dependency 'OnsideKit'
-  end
-
-  s.default_subspecs = []
+  # OnsideKit is optional; added via ensureOnsidePodIOS() in Podfile when modules.onside is enabled
+  # A post_install hook makes OnsideKit visible to ExpoIap so #if canImport(OnsideKit) works.
+  # Once OnsideKit is published to CocoaPods CDN, this can be replaced with a subspec dependency.
 
   # Swift/Objective-C compatibility
   s.pod_target_xcconfig = {

plugin/__tests__/withIAP.test.ts

@@ -195,13 +195,16 @@ describe('ensureOnsidePodIOS', () => {
     '',
   ].join('\n');
 
-  it('adds both OnsideKit and ExpoIap/Onside pods', () => {
+  it('adds OnsideKit pod and post_install hook', () => {
     const result = ensureOnsidePodIOS(basePodfile);
     expect(result).toContain("pod 'OnsideKit'");
-    expect(result).toContain("pod 'ExpoIap/Onside'");
+    expect(result).toContain('# [expo-iap] Make OnsideKit visible');
+    expect(result).toContain('post_install do |installer|');
+    expect(result).toContain("target.name == 'ExpoIap'");
+    expect(result).toContain('SWIFT_INCLUDE_PATHS');
   });
 
-  it('inserts pods inside the target block', () => {
+  it('inserts OnsideKit pod inside the target block', () => {
     const result = ensureOnsidePodIOS(basePodfile);
     const targetIndex = result.indexOf("target 'MyApp' do");
     const onsideKitIndex = result.indexOf("pod 'OnsideKit'");
@@ -210,38 +213,51 @@ describe('ensureOnsidePodIOS', () => {
     expect(onsideKitIndex).toBeLessThan(endIndex);
   });
 
-  it('skips if both pods already exist', () => {
-    const podfileWithBoth = [
+  it('appends into existing post_install block', () => {
+    const podfileWithPostInstall = [
       "target 'MyApp' do",
-      "  pod 'OnsideKit', :podspec => 'https://example.com'",
-      "  pod 'ExpoIap/Onside', :path => '../node_modules/expo-iap/ios'",
+      "  pod 'ExpoModulesCore'",
+      'end',
+      '',
+      'post_install do |installer|',
+      '  # existing hook',
       'end',
     ].join('\n');
-    const result = ensureOnsidePodIOS(podfileWithBoth);
-    expect(result).toBe(podfileWithBoth);
+    const result = ensureOnsidePodIOS(podfileWithPostInstall);
+    expect(result).toContain("pod 'OnsideKit'");
+    expect(result).toContain('# [expo-iap] Make OnsideKit visible');
+    // Should not create a second post_install block
+    const postInstallCount = (
+      result.match(/post_install do \|installer\|/g) ?? []
+    ).length;
+    expect(postInstallCount).toBe(1);
   });
 
-  it('adds missing ExpoIap/Onside when OnsideKit already exists', () => {
-    const podfileWithOnsideKit = [
+  it('skips if OnsideKit and post_install hook already exist', () => {
+    const podfileComplete = [
       "target 'MyApp' do",
       "  pod 'OnsideKit', :podspec => 'https://example.com'",
       'end',
+      '',
+      'post_install do |installer|',
+      '  # [expo-iap] Make OnsideKit visible',
+      'end',
     ].join('\n');
-    const result = ensureOnsidePodIOS(podfileWithOnsideKit);
-    expect(result).toContain("pod 'ExpoIap/Onside'");
-    expect(result).not.toContain('raw.githubusercontent');
+    const result = ensureOnsidePodIOS(podfileComplete);
+    expect(result).toBe(podfileComplete);
   });
 
-  it('adds missing OnsideKit when ExpoIap/Onside already exists', () => {
-    const podfileWithSubspec = [
+  it('adds post_install hook when OnsideKit already exists', () => {
+    const podfileWithOnsideKit = [
       "target 'MyApp' do",
-      "  pod 'ExpoIap/Onside', :path => '../node_modules/expo-iap/ios'",
+      "  pod 'OnsideKit', :podspec => 'https://example.com'",
       'end',
     ].join('\n');
-    const result = ensureOnsidePodIOS(podfileWithSubspec);
-    expect(result).toContain("pod 'OnsideKit'");
-    const subspecCount = (result.match(/pod 'ExpoIap\/Onside'/g) ?? []).length;
-    expect(subspecCount).toBe(1);
+    const result = ensureOnsidePodIOS(podfileWithOnsideKit);
+    expect(result).toContain('# [expo-iap] Make OnsideKit visible');
+    // Should not add a duplicate OnsideKit pod
+    const onsideKitCount = (result.match(/pod 'OnsideKit'/g) ?? []).length;
+    expect(onsideKitCount).toBe(1);
   });
 
   it('returns unchanged content when no target block found', () => {
@@ -260,7 +276,7 @@ describe('ensureOnsidePodIOS', () => {
 
     expect(content).toBe(basePodfile);
     expect(content).not.toContain("pod 'OnsideKit'");
-    expect(content).not.toContain("pod 'ExpoIap/Onside'");
+    expect(content).not.toContain('# [expo-iap] Make OnsideKit visible');
   });
 
   it('modifies Podfile when onside is enabled', () => {
@@ -273,6 +289,6 @@ describe('ensureOnsidePodIOS', () => {
 
     expect(content).not.toBe(basePodfile);
     expect(content).toContain("pod 'OnsideKit'");
-    expect(content).toContain("pod 'ExpoIap/Onside'");
+    expect(content).toContain('# [expo-iap] Make OnsideKit visible');
   });
 });

plugin/src/withIAP.ts

@@ -265,42 +265,72 @@ const withIapAndroid: ConfigPlugin<
 const ONSIDEKIT_PODSPEC_URL =
   'https://raw.githubusercontent.com/onside-io/OnsideKit-iOS/0.5.0/OnsideKit.podspec';
 
-const EXPO_IAP_IOS_PATH = '../node_modules/expo-iap/ios';
+// post_install hook that adds OnsideKit's module to ExpoIap's search paths
+// so that `#if canImport(OnsideKit)` resolves correctly at build time.
+// This is needed because OnsideKit is not yet on CocoaPods CDN, so we cannot
+// use a podspec `s.dependency`. Once OnsideKit is on CDN, replace with a subspec.
+const ONSIDE_POST_INSTALL_HOOK = `
+  # [expo-iap] Make OnsideKit visible to ExpoIap for #if canImport(OnsideKit)
+  installer.pods_project.targets.each do |target|
+    if target.name == 'ExpoIap'
+      target.build_configurations.each do |config|
+        swift_paths = config.build_settings['SWIFT_INCLUDE_PATHS'] || '$(inherited)'
+        onside_path = '\${PODS_CONFIGURATION_BUILD_DIR}/OnsideKit'
+        unless swift_paths.include?(onside_path)
+          config.build_settings['SWIFT_INCLUDE_PATHS'] = "#{swift_paths} #{onside_path}"
+        end
+      end
+    end
+  end`;
+
+const ONSIDE_POST_INSTALL_MARKER = '# [expo-iap] Make OnsideKit visible';
 
 export const ensureOnsidePodIOS = (content: string): string => {
   const alreadyHasOnsideKit = /^\s*pod\s+['"]OnsideKit['"].*$/m.test(content);
-  const alreadyHasExpoIapOnside = /^\s*pod\s+['"]ExpoIap\/Onside['"].*$/m.test(
-    content,
-  );
+  const alreadyHasPostInstall = content.includes(ONSIDE_POST_INSTALL_MARKER);
 
-  if (alreadyHasOnsideKit && alreadyHasExpoIapOnside) {
+  if (alreadyHasOnsideKit && alreadyHasPostInstall) {
     return content;
   }
 
-  const targetMatch = content.match(/target\s+'[^']+'\s+do\s*\n/);
-  if (!targetMatch) {
-    WarningAggregator.addWarningIOS(
-      'expo-iap',
-      'Could not find a target block in Podfile when adding ExpoIap/Onside; skipping installation.',
-    );
-    return content;
-  }
+  let result = content;
 
-  let podLines = '';
+  // 1) Add OnsideKit pod inside the target block
   if (!alreadyHasOnsideKit) {
-    podLines += `  pod 'OnsideKit', :podspec => '${ONSIDEKIT_PODSPEC_URL}'\n`;
-  }
-  if (!alreadyHasExpoIapOnside) {
-    podLines += `  pod 'ExpoIap/Onside', :path => '${EXPO_IAP_IOS_PATH}'\n`;
+    const targetMatch = result.match(/target\s+'[^']+'\s+do\s*\n/);
+    if (!targetMatch) {
+      WarningAggregator.addWarningIOS(
+        'expo-iap',
+        'Could not find a target block in Podfile when adding OnsideKit; skipping installation.',
+      );
+      return content;
+    }
+
+    const podLine = `  pod 'OnsideKit', :podspec => '${ONSIDEKIT_PODSPEC_URL}'\n`;
+    const insertIndex = targetMatch.index! + targetMatch[0].length;
+    result = result.slice(0, insertIndex) + podLine + result.slice(insertIndex);
   }
 
-  const insertIndex = targetMatch.index! + targetMatch[0].length;
-  const before = content.slice(0, insertIndex);
-  const after = content.slice(insertIndex);
+  // 2) Add post_install hook to make OnsideKit visible to ExpoIap
+  if (!alreadyHasPostInstall) {
+    const postInstallMatch = result.match(/post_install\s+do\s+\|installer\|/);
+    if (postInstallMatch) {
+      // Append inside existing post_install block
+      const insertIndex = postInstallMatch.index! + postInstallMatch[0].length;
+      result =
+        result.slice(0, insertIndex) +
+        '\n' +
+        ONSIDE_POST_INSTALL_HOOK +
+        result.slice(insertIndex);
+    } else {
+      // Create new post_install block
+      result += `\npost_install do |installer|${ONSIDE_POST_INSTALL_HOOK}\nend\n`;
+    }
+  }
 
-  logOnce('📦 expo-iap: Added ExpoIap/Onside subspec to Podfile');
+  logOnce('📦 expo-iap: Added OnsideKit pod and post_install hook to Podfile');
 
-  return `${before}${podLines}${after}`;
+  return result;
 };
 
 export type AutolinkState = {expoIap: boolean; onside: boolean};