[debugger] Fix NOT_IMPLEMENTED while debugging. (#19248)

- Changed the behavior on debugger-agent, if we can't parse the new behavior is to return invalid_argument and not assert and stop debugging
- Changed the mono_domain_set_fast before return from assembly_commands.
- Add error message when return INVALID_ARGUMENT

Fixes #19146

mcs/class/Mono.Debugger.Soft/Mono.Debugger.Soft/Connection.cs

@@ -393,6 +393,9 @@ namespace Mono.Debugger.Soft
 		public ErrorCode ErrorCode {
 			get; set;
 		}
+		public string ErrorMessage {
+			get; set;
+		}
 	}
 
 	/*
@@ -751,10 +754,12 @@ namespace Mono.Debugger.Soft
 
 				// For reply packets
 				offset = 0;
-				ReadInt (); // length
+				var len = ReadInt (); // length
 				ReadInt (); // id
 				ReadByte (); // flags
 				ErrorCode = ReadShort ();
+				if (ErrorCode == (int)Mono.Debugger.Soft.ErrorCode.INVALID_ARGUMENT && len > offset)
+					ErrorMsg = ReadString ();
 			}
 
 			public CommandSet CommandSet {
@@ -769,6 +774,10 @@ namespace Mono.Debugger.Soft
 				get; set;
 			}
 
+			public string ErrorMsg {
+				get; internal set;
+			}
+
 			public int Offset {
 				get {
 					return offset;
@@ -1570,7 +1579,7 @@ namespace Mono.Debugger.Soft
 							LogPacket (packetId, encoded_packet, reply, command_set, command, watch);
 						if (r.ErrorCode != 0) {
 							if (ErrorHandler != null)
-								ErrorHandler (this, new ErrorHandlerEventArgs () { ErrorCode = (ErrorCode)r.ErrorCode });
+								ErrorHandler (this, new ErrorHandlerEventArgs () { ErrorCode = (ErrorCode)r.ErrorCode, ErrorMessage = r.ErrorMsg});
 							throw new NotImplementedException ("No error handler set.");
 						} else {
 							return r;

mcs/class/Mono.Debugger.Soft/Mono.Debugger.Soft/VirtualMachine.cs

@@ -347,7 +347,7 @@ namespace Mono.Debugger.Soft
 			case ErrorCode.NO_SEQ_POINT_AT_IL_OFFSET:
 				throw new ArgumentException ("Cannot set breakpoint on the specified IL offset.");
 			default:
-				throw new CommandException (args.ErrorCode);
+				throw new CommandException (args.ErrorCode, args.ErrorMessage);
 			}
 		}
 
@@ -792,13 +792,18 @@ namespace Mono.Debugger.Soft
 
 	public class CommandException : Exception {
 
-		internal CommandException (ErrorCode error_code) : base ("Debuggee returned error code " + error_code + ".") {
+		internal CommandException (ErrorCode error_code, string error_message) : base ("Debuggee returned error code " + error_code + (error_message == null || error_message.Length == 0 ? "." : " - " + error_message + ".")) {
 			ErrorCode = error_code;
+			ErrorMessage = error_message;
 		}
 
 		public ErrorCode ErrorCode {
 			get; set;
 		}
+
+		public string ErrorMessage {
+			get; internal set;
+		}
 	}
 
 	public class VMNotSuspendedException : InvalidOperationException

mcs/class/Mono.Debugger.Soft/Test/dtest-app.cs

@@ -365,6 +365,9 @@ public class Tests : TestsBase, ITest2
 		if (args.Length > 0 && args [0] == "invoke-abort")
 			new Tests ().invoke_abort ();
 		new Tests ().evaluate_method ();
+
+		test_invalid_argument_assembly_get_type ();
+
 		return 3;
 	}
 
@@ -373,6 +376,10 @@ public class Tests : TestsBase, ITest2
 		LocalReflectClass.RunMe ();
 	}
 
+	public static void test_invalid_argument_assembly_get_type () {
+
+	}
+
 	public static void breakpoints () {
 		/* Call these early so it is JITted by the time a breakpoint is placed on it */
 		bp3 ();

mcs/class/Mono.Debugger.Soft/Test/dtest.cs

@@ -4431,5 +4431,18 @@ public class DebuggerTests
 		AssertValue (1, mirror["i"]);
 		AssertValue (2.0, mirror["d"]);
 	}
+
+	[Test]
+	public void InvalidArgumentAssemblyGetType () {
+		Event e = run_until ("test_invalid_argument_assembly_get_type");
+		var assembly = entry_point.DeclaringType.Assembly;
+		try {
+			var type = assembly.GetType ("System.Collections.Generic.Dictionary<double, float>.Main");
+		}
+		catch (CommandException ex) {
+			Assert.AreEqual(ex.ErrorMessage, "Unexpected assembly-qualified type \"System.Collections.Generic.Dictionary<double, float>.Main\" was provided");
+		}
+	}
+
 } // class DebuggerTests
 } // namespace

mono/mini/debugger-agent.c

@@ -9179,6 +9179,7 @@ vm_commands (int command, int id, guint8 *p, guint8 *end, Buffer *buf)
 		ignore_case = decode_byte (p, &p, end);
 
 		if (!mono_reflection_parse_type_checked (name, &info, &error)) {
+			buffer_add_string (buf, mono_error_get_message (&error));
 			mono_error_cleanup (&error);
 			g_free (name);
 			mono_reflection_free_type_info (&info);
@@ -9696,6 +9697,8 @@ assembly_commands (int command, guint8 *p, guint8 *end, Buffer *buf)
 	case CMD_ASSEMBLY_GET_TYPE: {
 		MonoError error;
 		char *s = decode_string (p, &p, end);
+		char* original_s = g_strdup_printf ("\"%s\"", s);
+
 		gboolean ignorecase = decode_byte (p, &p, end);
 		MonoTypeNameParse info;
 		MonoType *t;
@@ -9710,20 +9713,33 @@ assembly_commands (int command, guint8 *p, guint8 *end, Buffer *buf)
 			mono_error_cleanup (&error);
 			t = NULL;
 		} else {
-			if (info.assembly.name)
-				NOT_IMPLEMENTED;
+			if (info.assembly.name) {
+				mono_reflection_free_type_info (&info);
+				g_free (s);
+				mono_domain_set (d, TRUE);
+				char* error_msg =  g_strdup_printf ("Unexpected assembly-qualified type %s was provided", original_s);
+				buffer_add_string (buf, error_msg);
+				g_free (error_msg);
+				g_free (original_s);
+				return ERR_INVALID_ARGUMENT;
+			}
 			t = mono_reflection_get_type_checked (ass->image, ass->image, &info, ignorecase, &type_resolve, &error);
 			if (!is_ok (&error)) {
 				mono_error_cleanup (&error); /* FIXME don't swallow the error */
 				mono_reflection_free_type_info (&info);
 				g_free (s);
+				mono_domain_set (d, TRUE);
+				char* error_msg =  g_strdup_printf ("Invalid type name %s", original_s);
+				buffer_add_string (buf, error_msg);
+				g_free (error_msg);
+				g_free (original_s);
 				return ERR_INVALID_ARGUMENT;
 			}
 		}
 		buffer_add_typeid (buf, domain, t ? mono_class_from_mono_type (t) : NULL);
 		mono_reflection_free_type_info (&info);
 		g_free (s);
-
+		g_free (original_s);
 		mono_domain_set (d, TRUE);
 
 		break;
@@ -10689,6 +10705,7 @@ method_commands_internal (int command, MonoMethod *method, MonoDomain *domain, g
 
 		header = mono_method_get_header_checked (method, &error);
 		if (!header) {
+			buffer_add_string (buf, mono_error_get_message (&error));
 			mono_error_cleanup (&error); /* FIXME don't swallow the error */
 			return ERR_INVALID_ARGUMENT;
 		}
@@ -11576,7 +11593,7 @@ string_commands (int command, guint8 *p, guint8 *end, Buffer *buf)
 			if (!mono_error_ok (&error)) {
 				if (s)
 					g_free (s);
-
+				buffer_add_string (buf, mono_error_get_message (&error));
 				return ERR_INVALID_ARGUMENT;
 			}