Add support for single file analysis

src/linker/Linker.Dataflow/ReflectionMethodBodyScanner.cs

@@ -246,6 +246,11 @@ enum IntrinsicId
 			AppDomain_CreateInstanceFrom,
 			AppDomain_CreateInstanceFromAndUnwrap,
 			Assembly_CreateInstance,
+			Assembly_Location,
+			Assembly_CodeBase,
+			Assembly_EscapedCodeBase,
+			Assembly_GetFile,
+			Assembly_GetFiles,
 			RuntimeReflectionExtensions_GetRuntimeEvent,
 			RuntimeReflectionExtensions_GetRuntimeField,
 			RuntimeReflectionExtensions_GetRuntimeMethod,
@@ -481,6 +486,31 @@ static IntrinsicId GetIntrinsicIdForMethod (MethodDefinition calledMethod)
 					&& calledMethod.HasParameterOfType (0, "System", "String")
 					=> IntrinsicId.Assembly_CreateInstance,
 
+				// System.Reflection.Assembly.Location ()
+				"get_Location" when calledMethod.IsDeclaredOnType ("System.Reflection", "Assembly")
+					&& calledMethod.Parameters.Count == 0
+					=> IntrinsicId.Assembly_Location,
+
+				// System.Reflection.Assembly.CodeBase ()
+				"get_CodeBase" when calledMethod.IsDeclaredOnType ("System.Reflection", "AssemblyName")
+					&& calledMethod.Parameters.Count == 0
+					=> IntrinsicId.Assembly_CodeBase,
+
+				// System.Reflection.Assembly.EscapedCodeBase ()
+				"get_EscapedCodeBase" when calledMethod.IsDeclaredOnType ("System.Reflection", "AssemblyName")
+					&& calledMethod.Parameters.Count == 0
+					=> IntrinsicId.Assembly_EscapedCodeBase,
+
+				// System.Reflection.Assembly.GetFile (string)
+				"GetFile" when calledMethod.IsDeclaredOnType ("System.Reflection", "Assembly")
+					&& calledMethod.HasParameterOfType (0, "System", "String")
+					=> IntrinsicId.Assembly_GetFile,
+
+				// System.Reflection.Assembly.GetFiles ()
+				"GetFiles" when calledMethod.IsDeclaredOnType ("System.Reflection", "Assembly")
+					&& calledMethod.Parameters.Count == 0
+					=> IntrinsicId.Assembly_GetFiles,
+
 				// System.Runtime.CompilerServices.RuntimeHelpers.RunClassConstructor (RuntimeTypeHandle type)
 				"RunClassConstructor" when calledMethod.IsDeclaredOnType ("System.Runtime.CompilerServices", "RuntimeHelpers")
 					&& calledMethod.HasParameterOfType (0, "System", "RuntimeTypeHandle")
@@ -1227,6 +1257,52 @@ methodParams[argsParam] is ArrayValue arrayValue &&
 					reflectionContext.RecordUnrecognizedPattern (2058, $"Parameters passed to method '{calledMethodDefinition.GetDisplayName ()}' cannot be analyzed. Consider using methods 'System.Type.GetType' and `System.Activator.CreateInstance` instead.");
 					break;
 
+				//
+				// System.Reflection.Assembly
+				//
+				// Location ()
+				//
+				case IntrinsicId.Assembly_Location when _context.SingleFileAnalysis == true:
+					_context.LogWarning ($"'{calledMethodDefinition.GetDisplayName ()}' always returns an empty string for assemblies embedded in a single-file app. If the path to the app directory is needed, consider calling 'System.AppContext.BaseDirectory'.", 3000, callingMethodDefinition);
+					break;
+
+				//
+				// System.Reflection.Assembly
+				//
+				// CodeBase ()
+				//
+				case IntrinsicId.Assembly_CodeBase when _context.SingleFileAnalysis == true:
+					_context.LogWarning ($"'{calledMethodDefinition.GetDisplayName ()}' always returns an empty string for assemblies embedded in a single-file app. If the path to the app directory is needed, consider calling 'System.AppContext.BaseDirectory'.", 3000, callingMethodDefinition);
+					break;
+
+				//
+				// System.Reflection.Assembly
+				//
+				// EscapedCodeBase ()
+				//
+				case IntrinsicId.Assembly_EscapedCodeBase when _context.SingleFileAnalysis == true:
+					_context.LogWarning ($"'{calledMethodDefinition.GetDisplayName ()}' always returns an empty string for assemblies embedded in a single-file app. If the path to the app directory is needed, consider calling 'System.AppContext.BaseDirectory'.", 3000, callingMethodDefinition);
+					break;
+
+				//
+				// System.Reflection.Assembly
+				//
+				// GetFile (string fileName)
+				//
+				case IntrinsicId.Assembly_GetFile when _context.SingleFileAnalysis == true:
+					_context.LogWarning ($"Assemblies embedded in a single-file app cannot have additional files in the manifest.", 3001, callingMethodDefinition);
+					break;
+
+				//
+				// System.Reflection.Assembly
+				//
+				// GetFiles ()
+				//
+				case IntrinsicId.Assembly_GetFiles when _context.SingleFileAnalysis == true:
+					_context.LogWarning ($"Assemblies embedded in a single-file app cannot have additional files in the manifest.", 3001, callingMethodDefinition);
+					break;
+
+
 				//
 				// System.Runtime.CompilerServices.RuntimeHelpers
 				//

src/linker/Linker/Driver.cs

@@ -453,6 +453,12 @@ protected int SetupContext (ILogger customLogger = null)
 						context.NoWarn.UnionWith (ProcessWarningCodes (noWarnArgument));
 						continue;
 
+					case "--single-file-analysis":
+						if (!GetBoolParam (token, l => context.SingleFileAnalysis = l))
+							return -1;
+
+						continue;
+
 					case "--warnaserror":
 					case "--warnaserror+":
 						var warningList = GetNextStringValue ();

src/linker/Linker/LinkContext.cs

@@ -54,6 +54,7 @@ public class LinkContext : IDisposable
 		readonly Dictionary<string, string> _parameters;
 		bool _linkSymbols;
 		bool _keepTypeForwarderOnlyAssemblies;
+		bool _singleFileAnalysis;
 		bool _ignoreUnresolved;
 
 		readonly AssemblyResolver _resolver;
@@ -106,6 +107,11 @@ public bool KeepTypeForwarderOnlyAssemblies {
 			set { _keepTypeForwarderOnlyAssemblies = value; }
 		}
 
+		public bool SingleFileAnalysis {
+			get { return _singleFileAnalysis; }
+			set { _singleFileAnalysis = value; }
+		}
+
 #if FEATURE_ILLINK
 		public readonly bool KeepMembersForDebugger = true;
 #else

test/Mono.Linker.Tests.Cases/SingleFileAnalysis/SingleFileAnalysisIsNotSet.cs

@@ -0,0 +1,38 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+using Mono.Linker.Tests.Cases.Expectations.Assertions;
+using Mono.Linker.Tests.Cases.Expectations.Metadata;
+
+namespace Mono.Linker.Tests.Cases.SingleFileAnalysis
+{
+	public class SingleFileAnalysisIsNotSet
+	{
+		public static void Main ()
+		{
+			AssemblyLocationDoesNotWarn ();
+			AssemblyGetFileDoesNotWarn ();
+		}
+
+		[Kept]
+		[LogDoesNotContain ("IL3000")]
+		static string AssemblyLocationDoesNotWarn () => Assembly.GetExecutingAssembly ().Location;
+
+		[Kept]
+		[LogDoesNotContain ("IL3001")]
+		static void AssemblyGetFileDoesNotWarn ()
+		{
+			var a = Assembly.GetExecutingAssembly ();
+			_ = a.GetFile ("/some/file/path");
+			_ = a.GetFiles ();
+		}
+	}
+}

test/Mono.Linker.Tests.Cases/SingleFileAnalysis/WarnOnSingleFileDangerousPatterns.cs

@@ -0,0 +1,90 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+using Mono.Linker.Tests.Cases.Expectations.Assertions;
+using Mono.Linker.Tests.Cases.Expectations.Metadata;
+
+namespace Mono.Linker.Tests.Cases.SingleFileAnalysis
+{
+	[SetupLinkerArgument ("--single-file-analysis", "true")]
+	public class WarnOnSingleFileDangerousPatterns
+	{
+		public static void Main ()
+		{
+			GetExecutingAssemblyLocation ();
+			AssemblyProperties ();
+			AssemblyMethods ();
+			AssemblyNameAttributes ();
+			FalsePositive ();
+		}
+
+		[Kept]
+		[ExpectedWarning ("IL3000",
+			"'System.Reflection.Assembly.Location.get' always returns an empty string for assemblies embedded " +
+			"in a single-file app. If the path to the app directory is needed, consider calling 'System.AppContext.BaseDirectory'")]
+		static string GetExecutingAssemblyLocation () => Assembly.GetExecutingAssembly ().Location;
+
+		[Kept]
+		[ExpectedWarning ("IL3000",
+			"'System.Reflection.Assembly.Location.get' always returns an empty string for assemblies embedded " +
+			"in a single-file app. If the path to the app directory is needed, consider calling 'System.AppContext.BaseDirectory'")]
+		static void AssemblyProperties ()
+		{
+			var a = Assembly.GetExecutingAssembly ();
+			_ = a.Location;
+			// below methods are marked as obsolete in 5.0
+			// _ = a.CodeBase;
+			// _ = a.EscapedCodeBase;
+		}
+
+		[Kept]
+		[ExpectedWarning ("IL3001",
+			"Assemblies embedded in a single-file app cannot have additional files in the manifest.")]
+		[ExpectedWarning ("IL3001",
+			"Assemblies embedded in a single-file app cannot have additional files in the manifest.")]
+		static void AssemblyMethods ()
+		{
+			var a = Assembly.GetExecutingAssembly ();
+			_ = a.GetFile ("/some/file/path");
+			_ = a.GetFiles ();
+		}
+
+		[Kept]
+		[ExpectedWarning ("IL3000",
+			"'System.Reflection.AssemblyName.CodeBase.get' always returns an empty string for assemblies embedded " +
+			"in a single-file app. If the path to the app directory is needed, consider calling 'System.AppContext.BaseDirectory'.")]
+		[ExpectedWarning ("IL3000",
+			"'System.Reflection.AssemblyName.EscapedCodeBase.get' always returns an empty string for assemblies embedded " +
+			"in a single-file app. If the path to the app directory is needed, consider calling 'System.AppContext.BaseDirectory'.")]
+
+		static void AssemblyNameAttributes ()
+		{
+			var a = Assembly.GetExecutingAssembly ().GetName ();
+			_ = a.CodeBase;
+			_ = a.EscapedCodeBase;
+		}
+
+		// This is an OK use of Location and GetFile since these assemblies were loaded from
+		// a file, but the linker is conservative
+		[Kept]
+		[ExpectedWarning ("IL3000",
+			"'System.Reflection.Assembly.Location.get' always returns an empty string for assemblies embedded " +
+			"in a single-file app. If the path to the app directory is needed, consider calling 'System.AppContext.BaseDirectory'")]
+		[ExpectedWarning ("IL3001",
+			"Assemblies embedded in a single-file app cannot have additional files in the manifest.")]
+		static void FalsePositive ()
+		{
+			var a = Assembly.LoadFrom ("/some/path/not/in/bundle");
+			_ = a.Location;
+			_ = a.GetFiles ();
+		}
+	}
+}

test/Mono.Linker.Tests/TestCases/TestDatabase.cs

@@ -208,6 +208,11 @@ public static IEnumerable<TestCaseData> LinkAttributesTests ()
 			return NUnitCasesBySuiteName ("LinkAttributes");
 		}
 
+		public static IEnumerable<TestCaseData> SingleFileAnalysisTests ()
+		{
+			return NUnitCasesBySuiteName ("SingleFileAnalysis");
+		}
+
 		public static TestCaseCollector CreateCollector ()
 		{
 			GetDirectoryPaths (out string rootSourceDirectory, out string testCaseAssemblyPath);

test/Mono.Linker.Tests/TestCases/TestSuites.cs

@@ -248,6 +248,12 @@ public void LinkAttributesTests (TestCase testCase)
 			Run (testCase);
 		}
 
+		[TestCaseSource (typeof (TestDatabase), nameof (TestDatabase.SingleFileAnalysisTests))]
+		public void SingleFileAnalysisTests (TestCase testCase)
+		{
+			Run (testCase);
+		}
+
 		protected virtual void Run (TestCase testCase)
 		{
 			var runner = new TestRunner (new ObjectFactory ());