Fixed Version Control compatibility with Unity 2019.1+

Fixes #262
Bug: 138441374

Change-Id: I261628d816de2d5f11bf105253a36f88ec7de3df

Author: Stewart Miles

source/PlayServicesResolver/src/GradleTemplateResolver.cs

@@ -326,10 +326,10 @@ public static bool InjectDependencies(ICollection<Dependency> dependencies) {
                 }
                 outputLines.AddRange(currentOutputLines);
             }
-            if (!FileUtils.CheckoutFile(GradleTemplatePath))
-            {
+            if (!FileUtils.CheckoutFile(GradleTemplatePath, PlayServicesResolver.logger)) {
                 PlayServicesResolver.Log(
-                    String.Format("Unable to checkou '{0}'.", GradleTemplatePath), level: LogLevel.Error);
+                    String.Format("Failed to checkout '{0}', unable to patch the file.",
+                                  GradleTemplatePath), level: LogLevel.Error);
                 return false;
             }
             PlayServicesResolver.Log(

source/PlayServicesResolver/src/LocalMavenRepository.cs

@@ -129,9 +129,10 @@ public static bool PatchPomFile(string artifactFilename) {
                     updatedPackaging = true;
                 }
             }
-            if (!FileUtils.CheckoutFile(pomFilename))
-            {
-                PlayServicesResolver.Log(String.Format("Unable to checkout '{0}'.", pomFilename), LogLevel.Error);
+            if (!FileUtils.CheckoutFile(pomFilename, PlayServicesResolver.logger)) {
+                PlayServicesResolver.Log(
+                    String.Format("Unable to checkout '{0}' to patch the file for inclusion in a " +
+                                  "Gradle project.", pomFilename), LogLevel.Error);
                 return false;
             }
             if (updatedPackaging) {

source/PlayServicesResolver/src/PlayServicesResolver.cs

@@ -97,11 +97,11 @@ private static IEnumerable<string> SortSet(IEnumerable<string> setToSort) {
             public void WriteToFile() {
                 try {
                     Directory.CreateDirectory(Path.GetDirectoryName(DEPENDENCY_STATE_FILE));
-                    if (!FileUtils.CheckoutFile(DEPENDENCY_STATE_FILE))
-                    {
-                        logger.Log(
-                            String.Format("Unable to checkout '{0}'. Dependency state has not been saved!",
-                                DEPENDENCY_STATE_FILE), LogLevel.Error);
+                    if (!FileUtils.CheckoutFile(DEPENDENCY_STATE_FILE, logger)) {
+                        logger.Log(String.Format(
+                            "Unable to checkout '{0}'.  Resolution results can't be saved, " +
+                            "disabling auto-resolution.", DEPENDENCY_STATE_FILE), LogLevel.Error);
+                        SettingsDialogObj.EnableAutoResolution = false;
                         return;
                     }
                     using (var writer = new XmlTextWriter(new StreamWriter(DEPENDENCY_STATE_FILE)) {

source/VersionHandlerImpl/src/FileUtils.cs

@@ -293,21 +293,44 @@ public static string FindDirectoryByCaseInsensitivePath(string pathToFind) {
         /// Checks out a file should Version Control be active and valid.
         /// </summary>
         /// <param name="path">Path to the file that needs checking out.</param>
+        /// <param name="logger">Logger, used to log any error messages.</param>
         /// <returns>False should the checkout fail, otherwise true.</returns>
-        public static bool CheckoutFile(string path)
-        {
-            if (UnityEditor.VersionControl.Provider.enabled && UnityEditor.VersionControl.Provider.isActive &&
-                (!UnityEditor.VersionControl.Provider.requiresNetwork ||
-                 UnityEditor.VersionControl.Provider.onlineState == UnityEditor.VersionControl.OnlineState.Online))
-            {
-                var task = UnityEditor.VersionControl.Provider.Checkout(path,
-                    UnityEditor.VersionControl.CheckoutMode.Exact);
-                task.Wait();
-                if (!task.success)
-                    return false;
+        public static bool CheckoutFile(string path, Logger logger) {
+            try {
+                if (UnityEditor.VersionControl.Provider.enabled &&
+                    UnityEditor.VersionControl.Provider.isActive &&
+                    (!UnityEditor.VersionControl.Provider.requiresNetwork ||
+                     UnityEditor.VersionControl.Provider.onlineState ==
+                     UnityEditor.VersionControl.OnlineState.Online)) {
+                    // Unity 2019.1+ broke backwards compatibility of Checkout() by adding an
+                    // optional argument to the method so we dynamically invoke the method to add
+                    // the optional
+                    // argument for the Unity 2019.1+ overload at runtime.
+                    var task = (UnityEditor.VersionControl.Task)VersionHandler.InvokeStaticMethod(
+                        typeof(UnityEditor.VersionControl.Provider),
+                        "Checkout",
+                        new object[] { path, UnityEditor.VersionControl.CheckoutMode.Exact },
+                        namedArgs: null);
+                    task.Wait();
+                    if (!task.success) {
+                        var errorMessage = new List<string>();
+                        errorMessage.Add(String.Format("Failed to checkout {0}.", path));
+                        if (task.messages != null) {
+                            foreach (var message in task.messages) {
+                                if (message != null) errorMessage.Add(message.message);
+                            }
+                        }
+                        logger.Log(String.Join("\n", errorMessage.ToArray()),
+                                   level: LogLevel.Warning);
+                        return false;
+                    }
+                }
+                return true;
+            } catch (Exception ex) {
+                logger.Log(String.Format("Failed to checkout {0} ({1}.", path, ex),
+                           level: LogLevel.Warning);
+                return false;
             }
-
-            return true;
         }
     }
 }

source/VersionHandlerImpl/src/ProjectSettings.cs

@@ -406,11 +406,10 @@ private static void Save() {
                     return;
                 }
                 Directory.CreateDirectory(Path.GetDirectoryName(PROJECT_SETTINGS_FILE));
-                if (!FileUtils.CheckoutFile(PROJECT_SETTINGS_FILE))
-                {
+                if (!FileUtils.CheckoutFile(PROJECT_SETTINGS_FILE, logger)) {
                     logger.Log(
-                        String.Format("Unable to checkout '{0}'. Project settings have not been saved!",
-                            PROJECT_SETTINGS_FILE), LogLevel.Error);
+                        String.Format("Unable to checkout '{0}'. Project settings were not saved!",
+                                      PROJECT_SETTINGS_FILE), LogLevel.Error);
                     return;
                 }
                 using (var writer = new XmlTextWriter(new StreamWriter(PROJECT_SETTINGS_FILE)) {
@@ -430,4 +429,4 @@ private static void Save() {
             }
         }
     }
-}
+}