Fix AOT libs cooking to avoid file dirtying for more accurate iterative cooking

Source/Editor/Cooker/Steps/CompileScriptsStep.cpp

@@ -10,9 +10,10 @@
 #include "Engine/Serialization/JsonTools.h"
 #include "Engine/Serialization/JsonWriters.h"
 #include "Editor/Cooker/PlatformTools.h"
+#include "Engine/Engine/Globals.h"
 #include "Editor/Editor.h"
 #include "Editor/ProjectInfo.h"
-#include "Engine/Engine/Globals.h"
+#include "Editor/Utilities/EditorUtilities.h"
 #if PLATFORM_MAC
 #include <sys/stat.h>
 #endif
@@ -127,7 +128,7 @@ bool CompileScriptsStep::DeployBinaries(CookingData& data, const String& path, c
         const String dst = dstPath / StringUtils::GetFileName(file);
         if (dst == file)
             continue;
-        if (FileSystem::CopyFile(dst, file))
+        if (EditorUtilities::CopyFileIfNewer(dst, file))
         {
             data.Error(String::Format(TEXT("Failed to copy file from {0} to {1}."), file, dst));
             return true;

Source/Editor/Cooker/Steps/PrecompileAssembliesStep.cpp

@@ -59,6 +59,7 @@ bool PrecompileAssembliesStep::Perform(CookingData& data)
     data.StepProgress(infoMsg, 0);
 
     // Override Newtonsoft.Json with AOT-version (one that doesn't use System.Reflection.Emit)
+    // TODO: remove it since EngineModule does properly reference AOT lib now
     EditorUtilities::CopyFileIfNewer(data.ManagedCodeOutputPath / TEXT("Newtonsoft.Json.dll"), Globals::StartupFolder / TEXT("Source/Platforms/DotNet/AOT/Newtonsoft.Json.dll"));
     FileSystem::DeleteFile(data.ManagedCodeOutputPath / TEXT("Newtonsoft.Json.xml"));
     FileSystem::DeleteFile(data.ManagedCodeOutputPath / TEXT("Newtonsoft.Json.pdb"));

Source/Tools/Flax.Build/Build/DotNet/DotNetAOT.cs

@@ -462,7 +462,7 @@ namespace Flax.Build
                     else
                     {
                         // Copy to the destination folder
-                        Utilities.FileCopy(assemblyPath, Path.Combine(dotnetOutputPath, assemblyFileName));
+                        Utilities.FileCopy(assemblyPath, Path.Combine(dotnetOutputPath, assemblyFileName), Utilities.CopyMode.OverrideIfNewer);
                     }
                 };
                 if (Configuration.MaxConcurrency > 1 && Configuration.ConcurrencyProcessorScale > 0.0f && !dotnetAotDebug)

Source/Tools/Flax.Build/Build/EngineModule.cs

@@ -42,7 +42,8 @@ namespace Flax.Build
             BinaryModuleName = "FlaxEngine";
             options.ScriptingAPI.Defines.Add("FLAX");
             options.ScriptingAPI.Defines.Add("FLAX_ASSERTIONS");
-            options.ScriptingAPI.FileReferences.Add(Utilities.RemovePathRelativeParts(Path.Combine(Globals.EngineRoot, "Source", "Platforms", "DotNet", "Newtonsoft.Json.dll")));
+            var newtonsoftJsonPath = options.Platform?.HasDynamicCodeExecutionSupport ?? true ? "Newtonsoft.Json.dll" : "AOT/Newtonsoft.Json.dll";
+            options.ScriptingAPI.FileReferences.Add(Utilities.RemovePathRelativeParts(Path.Combine(Globals.EngineRoot, "Source", "Platforms", "DotNet", newtonsoftJsonPath)));
             options.ScriptingAPI.SystemReferences.Add("System.ComponentModel.TypeConverter");
         }
     }

Source/Tools/Flax.Build/Utilities/Utilities.cs

@@ -144,24 +144,51 @@ namespace Flax.Build
             return new TwoWayEnumerator<T>(source.GetEnumerator());
         }
 
+        /// <summary>
+        /// File copy modes.
+        /// </summary>
+        public enum CopyMode
+        {
+            /// <summary>
+            /// Copies the file to the destination, fails if it already exists.
+            /// </summary>
+            New,
+
+            /// <summary>
+            /// If destination file exists, it will be overriden.
+            /// </summary>
+            OverrideIfExists,
+
+            /// <summary>
+            /// If destination file exists, has the same size and is newer than source file, it won't be overriden (avoids unnecessary copies).
+            /// </summary>
+            OverrideIfNewer,
+        }
+
         /// <summary>
         /// Copies the file.
         /// </summary>
         /// <param name="srcFilePath">The source file path.</param>
         /// <param name="dstFilePath">The destination file path.</param>
-        /// <param name="overwrite"><see langword="true" /> if the destination file can be overwritten; otherwise, <see langword="false" />.</param>
-        public static void FileCopy(string srcFilePath, string dstFilePath, bool overwrite = true)
+        /// <param name="mode">Copy operation modes.</param>
+        public static void FileCopy(string srcFilePath, string dstFilePath, CopyMode mode = CopyMode.OverrideIfExists)
         {
             if (string.IsNullOrEmpty(srcFilePath))
                 throw new ArgumentNullException(nameof(srcFilePath));
             if (string.IsNullOrEmpty(dstFilePath))
                 throw new ArgumentNullException(nameof(dstFilePath));
 
+            if (mode == CopyMode.OverrideIfNewer &&
+                File.Exists(dstFilePath) &&
+                File.GetLastWriteTime(srcFilePath) <= File.GetLastWriteTime(dstFilePath) &&
+                new FileInfo(dstFilePath).Length == new FileInfo(srcFilePath).Length)
+                return;
+
             Log.Verbose(srcFilePath + " -> " + dstFilePath);
 
             try
             {
-                File.Copy(srcFilePath, dstFilePath, overwrite);
+                File.Copy(srcFilePath, dstFilePath, mode != CopyMode.New);
             }
             catch (Exception ex)
             {
@@ -173,6 +200,17 @@ namespace Flax.Build
             }
         }
 
+        /// <summary>
+        /// Copies the file.
+        /// </summary>
+        /// <param name="srcFilePath">The source file path.</param>
+        /// <param name="dstFilePath">The destination file path.</param>
+        /// <param name="overwrite"><see langword="true" /> if the destination file can be overwritten; otherwise, <see langword="false" />.</param>
+        public static void FileCopy(string srcFilePath, string dstFilePath, bool overwrite)
+        {
+            FileCopy(srcFilePath, dstFilePath, overwrite ? CopyMode.OverrideIfExists : CopyMode.New);
+        }
+
         /// <summary>
         /// Copies the directories.
         /// </summary>