[google_sign_in_ios] Adds Swift Package Manager support (flutter#7356)

Adds Swift Package Manager support to `google_sign_in_ios`.

Fixes flutter/flutter#146904

Author: loic-sharma

packages/google_sign_in/google_sign_in_ios/CHANGELOG.md

@@ -1,6 +1,7 @@
-## NEXT
+## 5.8.0
 
 * Updates minimum supported SDK version to Flutter 3.22/Dart 3.4.
+* Adds Swift Package Manager compatibility.
 
 ## 5.7.8
 

packages/google_sign_in/google_sign_in_ios/darwin/Assets/.gitkeep

@@ -11,7 +11,9 @@
 
 @import XCTest;
 @import google_sign_in_ios;
+#if __has_include(<google_sign_in_ios/google_sign_in_ios-umbrella.h>)
 @import google_sign_in_ios.Test;
+#endif
 @import GoogleSignIn;
 
 // OCMock library doesn't generate a valid modulemap.

packages/google_sign_in/google_sign_in_ios/darwin/Tests/GoogleSignInTests.m

@@ -12,9 +12,9 @@ Enables Google Sign-In in Flutter apps.
   s.license          = { :type => 'BSD', :file => '../LICENSE' }
   s.author           = { 'Flutter Team' => '[email protected]' }
   s.source           = { :http => 'https://github.com/flutter/packages/tree/main/packages/google_sign_in/google_sign_in_ios' }
-  s.source_files = 'Classes/**/*.{h,m}'
-  s.public_header_files = 'Classes/**/*.h'
-  s.module_map = 'Classes/FLTGoogleSignInPlugin.modulemap'
+  s.source_files = 'google_sign_in_ios/Sources/google_sign_in_ios/**/*.{h,m}'
+  s.public_header_files = 'google_sign_in_ios/Sources/google_sign_in_ios/include/**/*.h'
+  s.module_map = 'google_sign_in_ios/Sources/google_sign_in_ios/include/FLTGoogleSignInPlugin.modulemap'
 
   # AppAuth and GTMSessionFetcher are GoogleSignIn transitive dependencies.
   # Depend on versions which defines modules.
@@ -33,5 +33,5 @@ Enables Google Sign-In in Flutter apps.
   # GoogleSignIn depending a Swift pod (GTMAppAuth).
   s.swift_version = '5.0'
 
-  s.resource_bundles = {'google_sign_in_ios_privacy' => ['Resources/PrivacyInfo.xcprivacy']}
+  s.resource_bundles = {'google_sign_in_ios_privacy' => ['google_sign_in_ios/Sources/google_sign_in_ios/Resources/PrivacyInfo.xcprivacy']}
 end

packages/google_sign_in/google_sign_in_ios/darwin/google_sign_in_ios.podspec

@@ -0,0 +1,40 @@
+// swift-tools-version: 5.9
+
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import PackageDescription
+
+let package = Package(
+  name: "google_sign_in_ios",
+  platforms: [
+    .iOS("12.0"),
+    .macOS("10.15"),
+  ],
+  products: [
+    .library(name: "google-sign-in-ios", targets: ["google_sign_in_ios"])
+  ],
+  dependencies: [
+    .package(
+      url: "https://github.com/google/GoogleSignIn-iOS.git",
+      from: "7.1.0")
+  ],
+  targets: [
+    .target(
+      name: "google_sign_in_ios",
+      dependencies: [
+        .product(name: "GoogleSignIn", package: "GoogleSignIn-iOS")
+      ],
+      exclude: [
+        "include/google_sign_in_ios-umbrella.h", "include/FLTGoogleSignInPlugin.modulemap",
+      ],
+      resources: [
+        .process("Resources")
+      ],
+      cSettings: [
+        .headerSearchPath("include/google_sign_in_ios")
+      ]
+    )
+  ]
+)

packages/google_sign_in/google_sign_in_ios/darwin/google_sign_in_ios/Package.swift

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#import "FLTGoogleSignInPlugin.h"
-#import "FLTGoogleSignInPlugin_Test.h"
+#import "./include/google_sign_in_ios/FLTGoogleSignInPlugin.h"
+#import "./include/google_sign_in_ios/FLTGoogleSignInPlugin_Test.h"
 
 #import <GoogleSignIn/GoogleSignIn.h>