Fix covariant arrays (passing ASupertype[] where AType[] is expected)

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

@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using System.Windows.Forms;
 using BizHawk.Client.Common;
 
@@ -149,7 +150,7 @@ namespace BizHawk.Client.EmuHawk
 		public static FormatPreset DoFFmpegWriterDlg(IWin32Window owner, Config config)
 		{
 			FFmpegWriterForm dlg = new FFmpegWriterForm();
-			dlg.listBox1.Items.AddRange(FormatPreset.GetPresets(config.FFmpegCustomCommand));
+			dlg.listBox1.Items.AddRange(FormatPreset.GetPresets(config.FFmpegCustomCommand).Cast<object>().ToArray());
 
 			int i = dlg.listBox1.FindStringExact(config.FFmpegFormat);
 			if (i != ListBox.NoMatches)

src/BizHawk.Client.EmuHawk/Extensions/ControlExtensions.cs

@@ -27,9 +27,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 
 			box.Items.Clear();
-			box.Items.AddRange(
+			box.Items.AddRange(typeof(T).GetEnumDescriptions().Cast<object>().ToArray());
-				typeof(T).GetEnumDescriptions()
-				.ToArray());
 			box.SelectedItem = enumVal.GetDescription();
 		}
 

src/BizHawk.Client.EmuHawk/MainForm.Events.cs

@@ -1942,7 +1942,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			ZXSpectrumTapesSubMenu.DropDownItems.Clear();
 
-			var items = new List<ToolStripMenuItem>();
+			List<ToolStripItem> items = new();
 
 			if (Emulator is ZXSpectrum speccy)
 			{
@@ -1976,7 +1976,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			ZXSpectrumDisksSubMenu.DropDownItems.Clear();
 
-			var items = new List<ToolStripMenuItem>();
+			List<ToolStripItem> items = new();
 
 			if (Emulator is ZXSpectrum speccy)
 			{
@@ -2071,7 +2071,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			AmstradCPCTapesSubMenu.DropDownItems.Clear();
 
-			var items = new List<ToolStripMenuItem>();
+			List<ToolStripItem> items = new();
 
 			if (Emulator is AmstradCPC ams)
 			{
@@ -2105,7 +2105,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			AmstradCPCDisksSubMenu.DropDownItems.Clear();
 
-			var items = new List<ToolStripMenuItem>();
+			List<ToolStripItem> items = new();
 
 			if (Emulator is AmstradCPC ams)
 			{

src/BizHawk.Client.EmuHawk/config/FirmwaresConfig.cs

@@ -127,7 +127,7 @@ namespace BizHawk.Client.EmuHawk
 				= tbbOpenFolder.Image = Resources.Placeholder;
 
 			// prep ImageList for ListView with 3 item states for {idUnsure, idMissing, idOk}
-			imageList1.Images.AddRange(new[] { Resources.RetroQuestion, Resources.ExclamationRed, Resources.GreenCheck });
+			imageList1.Images.AddRange(new Image[] { Resources.RetroQuestion, Resources.ExclamationRed, Resources.GreenCheck });
 
 			_listViewSorter = new ListViewSorter(-1);
 

src/BizHawk.Client.EmuHawk/config/FirmwaresConfigInfo.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Drawing;
 using System.Windows.Forms;
 
 // todo - display details on the current resolution status
@@ -23,7 +24,7 @@ namespace BizHawk.Client.EmuHawk
 			InitializeComponent();
 
 			// prep imagelist for listview with 4 item states for (ideal, acceptable, unacceptable, bad)
-			imageList1.Images.AddRange(new[] { Properties.Resources.GreenCheck, Properties.Resources.Freeze, Properties.Resources.ThumbsDown, Properties.Resources.ExclamationRed });
+			imageList1.Images.AddRange(new Image[] { Properties.Resources.GreenCheck, Properties.Resources.Freeze, Properties.Resources.ThumbsDown, Properties.Resources.ExclamationRed });
 		}
 
 		private void LvOptions_KeyDown(object sender, KeyEventArgs e)

src/BizHawk.Client.EmuHawk/config/N64/N64VideoPluginconfig.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using System.Windows.Forms;
 
 using BizHawk.Common.StringExtensions;
@@ -205,7 +206,7 @@ namespace BizHawk.Client.EmuHawk
 
 			// Change resolution list to the rest
 			VideoResolutionComboBox.Items.Clear();
-			VideoResolutionComboBox.Items.AddRange(ValidResolutions);
+			VideoResolutionComboBox.Items.AddRange(ValidResolutions.Cast<object>().ToArray());
 
 			// If the given resolution is in the table, pick it.
 			// Otherwise find a best fit

src/BizHawk.Client.EmuHawk/config/NES/NESSyncSettingsForm.cs

@@ -37,7 +37,7 @@ namespace BizHawk.Client.EmuHawk
 				InfoLabel.Visible = true;
 			}
 
-			RegionComboBox.Items.AddRange(Enum.GetNames(typeof(NES.NESSyncSettings.Region)));
+			RegionComboBox.Items.AddRange(Enum.GetNames(typeof(NES.NESSyncSettings.Region)).Cast<object>().ToArray());
 			RegionComboBox.SelectedItem = Enum.GetName(typeof(NES.NESSyncSettings.Region), _syncSettings.RegionOverride);
 
 			if (_syncSettings.InitialWRamStatePattern != null && _syncSettings.InitialWRamStatePattern.Any())

src/BizHawk.Client.EmuHawk/config/NES/NesControllerSettings.cs

@@ -20,9 +20,9 @@ namespace BizHawk.Client.EmuHawk
 			Icon = Properties.Resources.GameControllerIcon;
 
 			// TODO: use combobox extension and add descriptions to enum values
-			comboBoxFamicom.Items.AddRange(NESControlSettings.GetFamicomExpansionValues().ToArray());
+			comboBoxFamicom.Items.AddRange(NESControlSettings.GetFamicomExpansionValues().Cast<object>().ToArray());
-			comboBoxNESL.Items.AddRange(NESControlSettings.GetNesPortValues().ToArray());
+			comboBoxNESL.Items.AddRange(NESControlSettings.GetNesPortValues().Cast<object>().ToArray());
-			comboBoxNESR.Items.AddRange(NESControlSettings.GetNesPortValues().ToArray());
+			comboBoxNESR.Items.AddRange(NESControlSettings.GetNesPortValues().Cast<object>().ToArray());
 
 			comboBoxFamicom.SelectedItem = _syncSettings.Controls.FamicomExpPort;
 			comboBoxNESL.SelectedItem = _syncSettings.Controls.NesLeftPort;

src/BizHawk.Client.EmuHawk/tools/BatchRun.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Windows.Forms;
 using System.Threading;
 using System.IO;
+using System.Linq;
 
 using BizHawk.Client.Common;
 using BizHawk.Emulation.Common;
@@ -41,7 +42,7 @@ namespace BizHawk.Client.EmuHawk
 			if (e.Data.GetDataPresent(DataFormats.FileDrop))
 			{
 				string[] files = (string[])e.Data.GetData(DataFormats.FileDrop);
-				listBox1.Items.AddRange(files);
+				listBox1.Items.AddRange(files.Cast<object>().ToArray());
 				SetCount();
 			}
 		}

src/BizHawk.Client.EmuHawk/tools/Cheats/CheatEdit.cs

@@ -43,7 +43,7 @@ namespace BizHawk.Client.EmuHawk
 			DomainDropDown.Items.Clear();
 			DomainDropDown.Items.AddRange(MemoryDomains
 				.Where(d => d.Writable)
-				.Select(d => d.ToString())
+				.Select(d => (object) d.ToString())
 				.ToArray());
 
 			DomainDropDown.SelectedItem = MemoryDomains.HasSystemBus

src/BizHawk.Client.EmuHawk/tools/Debugger/GenericDebugger.cs

@@ -61,7 +61,7 @@ namespace BizHawk.Client.EmuHawk
 							DropDownStyle = ComboBoxStyle.DropDownList
 						};
 
-						c.Items.AddRange(Disassembler.AvailableCpus.ToArray());
+						c.Items.AddRange(Disassembler.AvailableCpus.Cast<object>().ToArray());
 						c.SelectedItem = Disassembler.Cpu;
 						c.SelectedIndexChanged += OnCpuDropDownIndexChanged;
 

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Disk/UDIFormat/UDI1_0FloppyDisk.cs

@@ -170,7 +170,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			{
 				get
 				{
-					List<UDIv1Sector> secs = new List<UDIv1Sector>();
+					List<Sector> secs = new();
 					var datas = TrackData.Skip(3).Take(TLEN).ToArray();
 					var clocks = new BitArray(TrackData.Skip(3 + TLEN).Take(CLEN).ToArray());