Enable CA1806 and fix noncompliance (except in Cores)

return value implicitly discarded

Common.ruleset

@@ -209,7 +209,7 @@
 		<Rule Id="CA1805" Action="Hidden" />
 
 		<!-- Do not ignore method results -->
-		<Rule Id="CA1806" Action="Hidden" />
+		<Rule Id="CA1806" Action="Error" />
 
 		<!-- Initialize reference type static fields inline -->
 		<Rule Id="CA1810" Action="Hidden" />

src/BizHawk.BizInvoke/MemoryBlockLinuxPal.cs

@@ -31,7 +31,7 @@ namespace BizHawk.BizInvoke
 		{
 			if (_disposed)
 				return;
-			munmap(Z.US(Start), Z.UU(_size));
+			_ = munmap(Z.US(Start), Z.UU(_size));
 			_disposed = true;
 			GC.SuppressFinalize(this);
 		}

src/BizHawk.Client.Common/ArgParser.cs

@@ -98,7 +98,7 @@ namespace BizHawk.Client.Common
 				}
 				else if (argDowncased.StartsWith("--dump-length="))
 				{
-					int.TryParse(argDowncased.Substring(argDowncased.IndexOf('=') + 1), out var len);
+					var len = int.TryParse(argDowncased.Substring(argDowncased.IndexOf('=') + 1), out var i1) ? i1 : default;
 					autoDumpLength = len;
 				}
 				else if (argDowncased.StartsWith("--dump-close"))
@@ -125,7 +125,7 @@ namespace BizHawk.Client.Common
 				}
 				else if (argDowncased.StartsWith("--socket_port="))
 				{
-					int.TryParse(argDowncased.Substring(argDowncased.IndexOf('=') + 1), out var port);
+					var port = int.TryParse(argDowncased.Substring(argDowncased.IndexOf('=') + 1), out var i1) ? i1 : default;
 					if (port > 0) socketPort = port;
 				}
 				else if (argDowncased.StartsWith("--socket_ip="))

src/BizHawk.Client.Common/movie/import/DsmImport.cs

@@ -40,8 +40,7 @@ namespace BizHawk.Client.Common
 				}
 				else if (line.StartsWith("rerecordCount"))
 				{
-					int.TryParse(ParseHeader(line, "rerecordCount"), out var rerecordCount);
+					Result.Movie.Rerecords = (ulong) (int.TryParse(ParseHeader(line, "rerecordCount"), out var rerecordCount) ? rerecordCount : default);
-					Result.Movie.Rerecords = (ulong)rerecordCount;
 				}
 				else if (line.StartsWith("firmNickname"))
 				{

src/BizHawk.Client.Common/movie/import/Fm2Import.cs

@@ -97,8 +97,7 @@ namespace BizHawk.Client.Common
 				}
 				else if (line.ToLower().StartsWith("rerecordcount"))
 				{
-					int.TryParse(ParseHeader(line, "rerecordCount"), out var rerecordCount);
+					Result.Movie.Rerecords = (ulong) (int.TryParse(ParseHeader(line, "rerecordCount"), out var rerecordCount) ? rerecordCount : default);
-					Result.Movie.Rerecords = (ulong)rerecordCount;
 				}
 				else if (line.ToLower().StartsWith("guid"))
 				{

src/BizHawk.Client.Common/tools/Watch/WatchList/WatchValueComparer.cs

@@ -26,26 +26,13 @@ namespace BizHawk.Client.Common
 			/// <returns>0 for equality, 1 if x comes first; -1 if y comes first</returns>
 			public int Compare(Watch x, Watch y)
 			{
-				int xValue;
+				var xValue = x.Type is not WatchDisplayType.Signed
-				int yValue;
+					? x.Value
+					: int.TryParse(x.ValueString, out var i) ? i : default;
 
-				if (x.Type == WatchDisplayType.Signed)
+				var yValue = y.Type is not WatchDisplayType.Signed
-				{
+					? y.Value
-					int.TryParse(x.ValueString, out xValue);
+					: int.TryParse(y.ValueString, out var i1) ? i1 : default;
-				}
-				else
-				{
-					xValue = x.Value;
-				}
-
-				if (y.Type == WatchDisplayType.Signed)
-				{
-					int.TryParse(y.ValueString, out yValue);
-				}
-				else
-				{
-					yValue = y.Value;
-				}
 
 				if (Equals(x, y))
 				{

src/BizHawk.Client.EmuHawk/AVOut/AviWriter.cs

@@ -808,19 +808,19 @@ namespace BizHawk.Client.EmuHawk
 				CloseStreams();
 				if (_pAviRawAudioStream != IntPtr.Zero)
 				{
-					AVIWriterImports.AVIStreamRelease(_pAviRawAudioStream);
+					_ = AVIWriterImports.AVIStreamRelease(_pAviRawAudioStream);
 					_pAviRawAudioStream = IntPtr.Zero;
 				}
 
 				if (_pAviRawVideoStream != IntPtr.Zero)
 				{
-					AVIWriterImports.AVIStreamRelease(_pAviRawVideoStream);
+					_ = AVIWriterImports.AVIStreamRelease(_pAviRawVideoStream);
 					_pAviRawVideoStream = IntPtr.Zero;
 				}
 
 				if (_pAviFile != IntPtr.Zero)
 				{
-					AVIWriterImports.AVIFileRelease(_pAviFile);
+					_ = AVIWriterImports.AVIFileRelease(_pAviFile);
 					_pAviFile = IntPtr.Zero;
 				}
 
@@ -844,7 +844,7 @@ namespace BizHawk.Client.EmuHawk
 
 				if (_pAviCompressedVideoStream != IntPtr.Zero)
 				{
-					AVIWriterImports.AVIStreamRelease(_pAviCompressedVideoStream);
+					_ = AVIWriterImports.AVIStreamRelease(_pAviCompressedVideoStream);
 					_pAviCompressedVideoStream = IntPtr.Zero;
 				}
 			}
@@ -884,7 +884,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 
 				// (TODO - inefficient- build directly in a buffer)
-				AVIWriterImports.AVIStreamWrite(_pAviRawAudioStream, _outStatus.audio_samples, todo_realsamples, buf, todo_realsamples * 4, 0, IntPtr.Zero, out var bytes_written);
+				_ = AVIWriterImports.AVIStreamWrite(_pAviRawAudioStream, _outStatus.audio_samples, todo_realsamples, buf, todo_realsamples * 4, 0, IntPtr.Zero, out var bytes_written);
 				_outStatus.audio_samples += todo_realsamples;
 				_outStatus.audio_bytes += bytes_written;
 				_outStatus.audio_buffered_shorts = 0;

src/BizHawk.Client.EmuHawk/CustomControls/FolderBrowserDialogEx.cs

@@ -45,7 +45,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 
 			var hWndOwner = owner?.Handle ?? Win32Imports.GetActiveWindow();
-			Win32Imports.SHGetSpecialFolderLocation(hWndOwner, startLocation, out var pidlRoot);
+			_ = Win32Imports.SHGetSpecialFolderLocation(hWndOwner, startLocation, out var pidlRoot);
 			if (pidlRoot == IntPtr.Zero) return DialogResult.Cancel;
 			var mergedOptions = publicOptions | privateOptions;
 			if ((mergedOptions & Win32Imports.BROWSEINFO.FLAGS.NewDialogStyle) != 0 && ApartmentState.MTA == Application.OleRequired())
@@ -75,7 +75,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			finally
 			{
-				Win32Imports.SHGetMalloc(out var malloc);
+				_ = Win32Imports.SHGetMalloc(out var malloc);
 				malloc.Free(pidlRoot);
 				if (pidlRet != IntPtr.Zero) malloc.Free(pidlRet);
 			}

src/BizHawk.Client.EmuHawk/Program.cs

@@ -49,7 +49,7 @@ namespace BizHawk.Client.EmuHawk
 
 			// this will look in subdirectory "dll" to load pinvoked stuff
 			var dllDir = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "dll");
-			SetDllDirectory(dllDir);
+			_ = SetDllDirectory(dllDir);
 
 			//in case assembly resolution fails, such as if we moved them into the dll subdiretory, this event handler can reroute to them
 			AppDomain.CurrentDomain.AssemblyResolve += CurrentDomain_AssemblyResolve;
@@ -226,7 +226,7 @@ namespace BizHawk.Client.EmuHawk
 				//note: this is pasted instead of being put in a static method due to this initialization code being sensitive to things like that, and not wanting to cause it to break
 				//pasting should be safe (not affecting the jit order of things)
 				var dllDir = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "dll");
-				SetDllDirectory(dllDir);
+				_ = SetDllDirectory(dllDir);
 			}
 
 			Util.DebugWriteLine(EmuHawkUtil.CLRHostHasElevatedPrivileges ? "running as Superuser/Administrator" : "running as unprivileged user");

src/BizHawk.Emulation.Cores/BizHawk.Emulation.Cores.csproj

@@ -5,7 +5,7 @@
 	<Import Project="../MainSlnCommon.props" />
 	<PropertyGroup>
 		<AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-		<NoWarn>$(NoWarn);CA2214;SA1100;SA1120;SA1137;SA1205;SA1208;SA1400</NoWarn>
+		<NoWarn>$(NoWarn);CA1806;CA2214;SA1100;SA1120;SA1137;SA1205;SA1208;SA1400</NoWarn>
 		<Nullable>disable</Nullable>
 	</PropertyGroup>
 	<ItemGroup>

src/BizHawk.Emulation.DiscSystem/API_MednaDisc.cs

@@ -44,7 +44,7 @@ namespace BizHawk.Emulation.DiscSystem
 		{
 			//read directly into the target buffer
 			fixed(byte* pBuffer = &buffer[0])
-				mednadisc_ReadSector(handle, LBA, pBuffer + offset);
+				_ = mednadisc_ReadSector(handle, LBA, pBuffer + offset);
 		}
 
 #if false