Tests: Reuse decompiler roundtrip assertion code

This contains no functional changes, except that
it will ignore blank lines when comparing code.

This reduces duplicate code, and will make it
easier to add assertions for Roslyn compilers

ICSharpCode.Decompiler/Tests/DecompilerTestBase.cs

@@ -35,10 +35,8 @@ namespace ICSharpCode.Decompiler.Tests
 	{
 		protected static void ValidateFileRoundtrip(string samplesFileName)
 		{
-			var lines = File.ReadAllLines(Path.Combine(@"..\..\Tests", samplesFileName));
+			var fullPath = Path.Combine(@"..\..\Tests", samplesFileName);
-			var testCode = RemoveIgnorableLines(lines);
+			AssertRoundtripCode(fullPath);
-			var decompiledTestCode = RoundtripCode(testCode);
-			CodeAssert.AreEqual(testCode, decompiledTestCode);
 		}
 
 		static string RemoveIgnorableLines(IEnumerable<string> lines)
@@ -46,28 +44,25 @@ namespace ICSharpCode.Decompiler.Tests
 			return CodeSampleFileParser.ConcatLines(lines.Where(l => !CodeSampleFileParser.IsCommentOrBlank(l)));
 		}
 
-		/// <summary>
+		protected static void AssertRoundtripCode(string fileName, bool optimize = false, bool useDebug = false)
-		/// Compiles and decompiles a source code.
-		/// </summary>
-		/// <param name="code">The source code to copile.</param>
-		/// <returns>The decompilation result of compiled source code.</returns>
-		static string RoundtripCode(string code)
 		{
-			DecompilerSettings settings = new DecompilerSettings();
+			var code = RemoveIgnorableLines(File.ReadLines(fileName));
-			settings.FullyQualifyAmbiguousTypeNames = false;
+			AssemblyDefinition assembly = CompileLegacy(code, optimize, useDebug);
-			AssemblyDefinition assembly = Compile(code);
+
-			AstBuilder decompiler = new AstBuilder(new DecompilerContext(assembly.MainModule) { Settings = settings });
+			AstBuilder decompiler = new AstBuilder(new DecompilerContext(assembly.MainModule));
 			decompiler.AddAssembly(assembly);
 			new Helpers.RemoveCompilerAttribute().Run(decompiler.SyntaxTree);
+
 			StringWriter output = new StringWriter();
 			decompiler.GenerateCode(new PlainTextOutput(output));
-			return output.ToString();
+			CodeAssert.AreEqual(code, output.ToString());
 		}
 
-		static AssemblyDefinition Compile(string code)
+		protected static AssemblyDefinition CompileLegacy(string code, bool optimize, bool useDebug)
 		{
 			CSharpCodeProvider provider = new CSharpCodeProvider(new Dictionary<string, string> { { "CompilerVersion", "v4.0" } });
 			CompilerParameters options = new CompilerParameters();
+			options.CompilerOptions = "/unsafe /o" + (optimize ? "+" : "-") + (useDebug ? " /debug" : "");
 			options.ReferencedAssemblies.Add("System.Core.dll");
 			CompilerResults results = provider.CompileAssemblyFromSource(options, code);
 			try

ICSharpCode.Decompiler/Tests/Helpers/CodeAssert.cs

@@ -104,7 +104,7 @@ namespace ICSharpCode.Decompiler.Tests.Helpers
 
 		private static IEnumerable<string> NormalizeAndSplitCode(string input)
 		{
-			return input.Split(new[] { "\r\n", "\n\r", "\n", "\r" }, StringSplitOptions.None);
+			return input.Split(new[] { "\r\n", "\n\r", "\n", "\r" }, StringSplitOptions.RemoveEmptyEntries);
 		}
 	}
 }

ICSharpCode.Decompiler/Tests/TestRunner.cs

@@ -32,7 +32,7 @@ using NUnit.Framework;
 namespace ICSharpCode.Decompiler.Tests
 {
 	[TestFixture]
-	public class TestRunner
+	public class TestRunner : DecompilerTestBase
 	{
 		[Test]
 		public void Async()
@@ -67,7 +67,8 @@ namespace ICSharpCode.Decompiler.Tests
 		[Test]
 		public void ExceptionHandling()
 		{
-			TestFile(@"..\..\Tests\ExceptionHandling.cs", optimize: false);
+			AssertRoundtripCode(@"..\..\Tests\ExceptionHandling.cs", optimize: false);
+			AssertRoundtripCode(@"..\..\Tests\ExceptionHandling.cs", optimize: false);
 		}
 		
 		[Test]
@@ -85,7 +86,8 @@ namespace ICSharpCode.Decompiler.Tests
 		[Test]
 		public void ControlFlowWithDebug()
 		{
-			TestFile(@"..\..\Tests\ControlFlow.cs", optimize: false, useDebug: true);
+			AssertRoundtripCode(@"..\..\Tests\ControlFlow.cs", optimize: false, useDebug: true);
+			AssertRoundtripCode(@"..\..\Tests\ControlFlow.cs", optimize: false, useDebug: true);
 		}
 		
 		[Test]
@@ -180,42 +182,10 @@ namespace ICSharpCode.Decompiler.Tests
 		
 		static void TestFile(string fileName, bool useDebug = false)
 		{
-			TestFile(fileName, false, useDebug);
+			AssertRoundtripCode(fileName, optimize: false, useDebug: useDebug);
-			TestFile(fileName, true, useDebug);
+			AssertRoundtripCode(fileName, optimize: true, useDebug: useDebug);
-		}
+			AssertRoundtripCode(fileName, optimize: false, useDebug: useDebug);
-
+			AssertRoundtripCode(fileName, optimize: true, useDebug: useDebug);
-		static void TestFile(string fileName, bool optimize, bool useDebug = false)
-		{
-			string code = File.ReadAllText(fileName);
-			AssemblyDefinition assembly = Compile(code, optimize, useDebug);
-			AstBuilder decompiler = new AstBuilder(new DecompilerContext(assembly.MainModule));
-			decompiler.AddAssembly(assembly);
-			new Helpers.RemoveCompilerAttribute().Run(decompiler.SyntaxTree);
-			StringWriter output = new StringWriter();
-			decompiler.GenerateCode(new PlainTextOutput(output));
-			CodeAssert.AreEqual(code, output.ToString());
-		}
-
-		static AssemblyDefinition Compile(string code, bool optimize, bool useDebug)
-		{
-			CSharpCodeProvider provider = new CSharpCodeProvider(new Dictionary<string, string> { { "CompilerVersion", "v4.0" } });
-			CompilerParameters options = new CompilerParameters();
-			options.CompilerOptions = "/unsafe /o" + (optimize ? "+" : "-") + (useDebug ? " /debug": "");
-			options.ReferencedAssemblies.Add("System.Core.dll");
-			CompilerResults results = provider.CompileAssemblyFromSource(options, code);
-			try {
-				if (results.Errors.Count > 0) {
-					StringBuilder b = new StringBuilder("Compiler error:");
-					foreach (var error in results.Errors) {
-						b.AppendLine(error.ToString());
-					}
-					throw new Exception(b.ToString());
-				}
-				return AssemblyDefinition.ReadAssembly(results.PathToAssembly);
-			} finally {
-				File.Delete(results.PathToAssembly);
-				results.TempFiles.Delete();
-			}
 		}
 	}
 }