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Source/Tools/Flax.Build/Build/Assembler.cs

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+// Copyright (c) 2012-2020 Flax Engine. All rights reserved.
+
+using System;
+using System.CodeDom.Compiler;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+
+namespace Flax.Build
+{
+    /// <summary>
+    /// Utility for building C# assemblies from custom set of source files.
+    /// </summary>
+    public class Assembler
+    {
+        /// <summary>
+        /// The default assembly references added to the projects.
+        /// </summary>
+        public static readonly Assembly[] DefaultReferences =
+        {
+            typeof(IntPtr).Assembly, // mscorlib.dll
+            typeof(Enumerable).Assembly, // System.Linq.dll
+            typeof(ISet<>).Assembly, // System.dll
+            typeof(Builder).Assembly, // Flax.Build.exe
+        };
+
+        /// <summary>
+        /// The output assembly path. Use null to store assembly in the process memory.
+        /// </summary>
+        public string OutputPath = null;
+
+        /// <summary>
+        /// The source files for compilation.
+        /// </summary>
+        public readonly List<string> SourceFiles = new List<string>();
+
+        /// <summary>
+        /// The external user assembly references to use while compiling
+        /// </summary>
+        public readonly List<Assembly> Assemblies = new List<Assembly>();
+
+        /// <summary>
+        /// The external user assembly file names to use while compiling
+        /// </summary>
+        public readonly List<string> References = new List<string>();
+
+        /// <summary>
+        /// Builds the assembly.
+        /// </summary>
+        /// <remarks>Throws an exception in case of any errors.</remarks>
+        /// <returns>The created and loaded assembly.</returns>
+        public Assembly Build()
+        {
+            Dictionary<string, string> providerOptions = new Dictionary<string, string>();
+            providerOptions.Add("CompilerVersion", "v4.0");
+            CodeDomProvider provider = new Microsoft.CSharp.CSharpCodeProvider(providerOptions);
+
+            // Collect references
+            HashSet<string> references = new HashSet<string>();
+            foreach (var defaultReference in DefaultReferences)
+                references.Add(defaultReference.Location);
+            foreach (var assemblyFile in References)
+                references.Add(assemblyFile);
+            foreach (var assembly in Assemblies)
+                if (!assembly.IsDynamic)
+                    references.Add(assembly.Location);
+
+            // Setup compilation options
+            CompilerParameters cp = new CompilerParameters();
+            cp.GenerateExecutable = false;
+            cp.WarningLevel = 4;
+            cp.TreatWarningsAsErrors = false;
+            cp.ReferencedAssemblies.AddRange(references.ToArray());
+            if (string.IsNullOrEmpty(OutputPath))
+            {
+                cp.GenerateInMemory = true;
+                cp.IncludeDebugInformation = false;
+            }
+            else
+            {
+                cp.GenerateInMemory = false;
+                cp.IncludeDebugInformation = true;
+                cp.OutputAssembly = OutputPath;
+            }
+
+            // HACK: C# will give compilation errors if a LIB variable contains non-existing directories
+            Environment.SetEnvironmentVariable("LIB", null);
+
+            // Run the compilation
+            CompilerResults cr = provider.CompileAssemblyFromFile(cp, SourceFiles.ToArray());
+
+            // Process warnings
+            if (cr.Errors.HasWarnings)
+            {
+                foreach (CompilerError ce in cr.Errors)
+                {
+                    if (ce.IsWarning)
+                    {
+                        Log.Warning(string.Format("{0} at {1}: {2}", ce.FileName, ce.Line, ce.ErrorText));
+                    }
+                }
+            }
+
+            // Process errors
+            if (cr.Errors.HasErrors)
+            {
+                foreach (CompilerError ce in cr.Errors)
+                {
+                    if (!ce.IsWarning)
+                    {
+                        Log.Error(string.Format("{0} at line {1}: {2}", ce.FileName, ce.Line, ce.ErrorText));
+                    }
+                }
+
+                throw new Exception("Failed to build assembly.");
+            }
+
+            return cr.CompiledAssembly;
+        }
+    }
+}