fix: add missing test for merging Podfiles

Add missing test for #3935

Author: rosen-vladimirov

test/cocoapods-service.ts

@@ -306,6 +306,50 @@ end
 post_install do |installer|
 	post_installplugin1_0 installer
 end
+end`,
+			},
+			{
+				testCaseDescription: "adds plugin with postinstall when project's Podfile has content, but does not have postinstall",
+				input: `
+target 'MyApp' do
+	pod 'GoogleAnalytics', '~> 3.1'
+end
+
+post_install do |installer|
+	installer.pods_project.targets.each do |target|
+		puts target.name
+	end
+end`,
+				output: `use_frameworks!
+
+target "projectName" do
+# Begin Podfile - pluginPlatformsFolderPath/Podfile
+
+target 'MyApp' do
+	pod 'GoogleAnalytics', '~> 3.1'
+end
+
+def post_installplugin1_0 (installer)
+	installer.pods_project.targets.each do |target|
+		puts target.name
+	end
+end
+# End Podfile
+
+# Begin Podfile - secondPluginPlatformsFolderPath/Podfile
+pod 'OCMock', '~> 2.0.1'
+# End Podfile
+
+post_install do |installer|
+  post_installplugin1_0 installer
+end
+end`,
+				projectPodfileContent: `use_frameworks!
+
+target "projectName" do
+# Begin Podfile - secondPluginPlatformsFolderPath/Podfile
+pod 'OCMock', '~> 2.0.1'
+# End Podfile
 end`,
 			},
 			{