gui-cs.Terminal.Gui/UnitTests/Input/KeyTests.cs

using System;
using System.Text;
using Xunit;
using Xunit.Abstractions;

namespace Terminal.Gui.InputTests;

public class KeyTests {
	readonly ITestOutputHelper _output;

	public KeyTests (ITestOutputHelper output) => _output = output;


	[Fact]
	public void Constructor_Default_ShouldSetKeyToNull ()
	{
		var eventArgs = new Key ();
		Assert.Equal (KeyCode.Null, eventArgs.KeyCode);
	}

	[Theory]
	[InlineData (KeyCode.Enter)]
	[InlineData (KeyCode.Esc)]
	[InlineData (KeyCode.A)]
	public void Constructor_WithKey_ShouldSetCorrectKey (KeyCode key)
	{
		var eventArgs = new Key (key);
		Assert.Equal (key, eventArgs.KeyCode);
	}

	[Theory]
	[InlineData ('a',  KeyCode.A)]
	[InlineData ('A',  KeyCode.A | KeyCode.ShiftMask)]
	[InlineData ('z',  KeyCode.Z)]
	[InlineData ('Z',  KeyCode.Z | KeyCode.ShiftMask)]
	[InlineData (' ',  KeyCode.Space)]
	[InlineData ('1',  KeyCode.D1)]
	[InlineData ('!',  (KeyCode)'!')]
	[InlineData ('\r', KeyCode.Enter)]
	[InlineData ('\t', KeyCode.Tab)]
#pragma warning disable xUnit1025 // InlineData should be unique within the Theory it belongs to
	[InlineData ('\r', (KeyCode)13)]
#pragma warning restore xUnit1025 // InlineData should be unique within the Theory it belongs to
	[InlineData ('\n',     (KeyCode)10)]
	[InlineData ('ó',      (KeyCode)'ó')]
	[InlineData ('Ó',      (KeyCode)'Ó')]
	[InlineData ('❿',      (KeyCode)'❿')]
	[InlineData ('☑',      (KeyCode)'☑')]
	[InlineData ('英',      (KeyCode)'英')]
	[InlineData ('{',      (KeyCode)'{')]
	[InlineData ('\'',     (KeyCode)'\'')]
	[InlineData ('\xFFFF', (KeyCode)0xFFFF)]
	[InlineData ('\x0',    (KeyCode)0x0)]
	public void Constructor_Char (char ch, KeyCode expectedKeyCode)
	{
		var key = new Key (ch);
		Assert.Equal (expectedKeyCode, key.KeyCode);
	}


	// Via https://andrewlock.net/creating-parameterised-tests-in-xunit-with-inlinedata-classdata-and-memberdata/
	public static TheoryData<string, Key> ValidStrings =>
	new () {
	{ "a", new Key (KeyCode.A) },
	{ "Ctrl+A", new Key (KeyCode.A | KeyCode.CtrlMask) },
	{ "Alt+A", new Key (KeyCode.A | KeyCode.AltMask) },
	{ "Shift+A", new Key (KeyCode.A | KeyCode.ShiftMask) },
	{ "A", new Key (KeyCode.A | KeyCode.ShiftMask) },
	{ "â", new Key ((KeyCode)'â') },
	{ "Shift+â", new Key ((KeyCode)'â' | KeyCode.ShiftMask) },
	{ "Shift+Â", new Key ((KeyCode)'Â' | KeyCode.ShiftMask) },
	{ "Ctrl+Shift+CursorUp", new Key (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.CursorUp) },
	{ "Ctrl+Alt+Shift+CursorUp", new Key (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.CursorUp) },
	{ "ctrl+alt+shift+cursorup", new Key (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.CursorUp) },
	{ "CTRL+ALT+SHIFT+CURSORUP", new Key (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.CursorUp) },
	{ "Ctrl+Alt+Shift+Delete", new Key (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Delete) },
	{ "Ctrl+Alt+Shift+Enter", new Key (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Enter) },
	{ "Tab", new Key (KeyCode.Tab) },
	{ "Shift+Tab", new Key (KeyCode.Tab | KeyCode.ShiftMask) },
	{ "Ctrl+Tab", new Key (KeyCode.Tab | KeyCode.CtrlMask) },
	{ "Alt+Tab", new Key (KeyCode.Tab | KeyCode.AltMask) },
	{ "Ctrl+Shift+Tab", new Key (KeyCode.Tab | KeyCode.ShiftMask | KeyCode.CtrlMask) },
	{ "Ctrl+Alt+Tab", new Key (KeyCode.Tab | KeyCode.AltMask | KeyCode.CtrlMask) },
	{ "", new Key (KeyCode.Null) },
	{ " ", new Key (KeyCode.Space) },
	{ "Space", new Key (KeyCode.Space) },
	{ "Shift+Space", new Key (KeyCode.Space | KeyCode.ShiftMask) },
	{ "Ctrl+Space", new Key (KeyCode.Space | KeyCode.CtrlMask) },
	{ "Alt+Space", new Key (KeyCode.Space | KeyCode.AltMask) },
	{ "Shift+ ", new Key (KeyCode.Space | KeyCode.ShiftMask) },
	{ "Ctrl+ ", new Key (KeyCode.Space | KeyCode.CtrlMask) },
	{ "Alt+ ", new Key (KeyCode.Space | KeyCode.AltMask) },
	{ "F1", new Key (KeyCode.F1) },
	{ "0", new Key (KeyCode.D0) },
	{ "9", new Key (KeyCode.D9) },
	{ "D0", new Key (KeyCode.D0) },
	{ "65", new Key (KeyCode.A | KeyCode.ShiftMask) },
	{ "97", new Key (KeyCode.A) },
	{ "Shift", new Key (KeyCode.ShiftMask) },
	{ "Ctrl", new Key (KeyCode.CtrlMask) },
	{ "Ctrl-A", new Key (KeyCode.A | KeyCode.CtrlMask) },
	{ "Alt-A", new Key (KeyCode.A | KeyCode.AltMask) },
	{ "A-Ctrl", new Key (KeyCode.A | KeyCode.CtrlMask) },
	{ "Alt-A-Ctrl", new Key (KeyCode.A | KeyCode.CtrlMask | KeyCode.AltMask) }
	};

	[Theory]
	[MemberData (nameof (ValidStrings))]
	public void Constructor_String_Valid (string keyString, Key expected)
	{
		var key = new Key (keyString);
		Assert.Equal (expected.ToString (), key.ToString ());
	}


	[Theory]
	[InlineData ("Barf")]
	public void Constructor_String_Invalid_Throws (string keyString) => Assert.Throws<ArgumentException> (() => new Key (keyString));

	[Theory]
	[InlineData ('a',  KeyCode.A)]
	[InlineData ('A',  KeyCode.A | KeyCode.ShiftMask)]
	[InlineData ('z',  KeyCode.Z)]
	[InlineData ('Z',  KeyCode.Z | KeyCode.ShiftMask)]
	[InlineData (' ',  KeyCode.Space)]
	[InlineData ('1',  KeyCode.D1)]
	[InlineData ('!',  (KeyCode)'!')]
	[InlineData ('\r', KeyCode.Enter)]
	[InlineData ('\t', KeyCode.Tab)]
#pragma warning disable xUnit1025 // InlineData should be unique within the Theory it belongs to
	[InlineData ('\r', (KeyCode)13)]
#pragma warning restore xUnit1025 // InlineData should be unique within the Theory it belongs to
	[InlineData ('\n',     (KeyCode)10)]
	[InlineData ('ó',      (KeyCode)'ó')]
	[InlineData ('Ó',      (KeyCode)'Ó')]
	[InlineData ('❿',      (KeyCode)'❿')]
	[InlineData ('☑',      (KeyCode)'☑')]
	[InlineData ('英',      (KeyCode)'英')]
	[InlineData ('{',      (KeyCode)'{')]
	[InlineData ('\'',     (KeyCode)'\'')]
	[InlineData ('\xFFFF', (KeyCode)0xFFFF)]
	[InlineData ('\x0',    (KeyCode)0x0)]
	public void Cast_Char_To_Key (char ch, KeyCode expectedKeyCode)
	{
		var key = (Key)ch;
		Assert.Equal (expectedKeyCode, key.KeyCode);
	}

	// string cast operators
	[Fact]
	public void Cast_String_To_Key ()
	{
		var key = (Key)"Ctrl+Q";
		Assert.Equal (KeyCode.Q | KeyCode.CtrlMask, key.KeyCode);
	}

	[Fact]
	public void Cast_Key_ToString ()
	{
		var str = (string)Key.Q.WithCtrl;
		Assert.Equal ("Ctrl+Q", str);
	}

	// IsValid
	[Theory]
	[InlineData (KeyCode.A,                           true)]
	[InlineData (KeyCode.B,                           true)]
	[InlineData (KeyCode.F1 | KeyCode.ShiftMask,      true)]
	[InlineData (KeyCode.Null,                        false)]
	[InlineData (KeyCode.ShiftMask,                   false)]
	[InlineData (KeyCode.CtrlMask,                    false)]
	[InlineData (KeyCode.AltMask,                     false)]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask, false)]
	public void IsValid (KeyCode key, bool expected) => Assert.Equal (expected, ((Key)key).IsValid);

	[Fact]
	public void HandledProperty_ShouldBeFalseByDefault ()
	{
		var eventArgs = new Key ();
		Assert.False (eventArgs.Handled);
	}

	[Theory]
	[InlineData (KeyCode.Enter,                 KeyCode.Enter)]
	[InlineData (KeyCode.Esc,                   KeyCode.Esc)]
	[InlineData (KeyCode.A,                     (KeyCode)'a')]
	[InlineData (KeyCode.A | KeyCode.ShiftMask, KeyCode.A | KeyCode.ShiftMask)]
	[InlineData (KeyCode.Z,                     (KeyCode)'z')]
	[InlineData (KeyCode.Space,                 KeyCode.Space)]
	public void Cast_KeyCode_To_Key (KeyCode cdk, KeyCode expected)
	{
		// explicit
		var key = (Key)cdk;
		Assert.Equal (((Key)expected).ToString (), key.ToString ());

		// implicit
		key = cdk;
		Assert.Equal (((Key)expected).ToString (), key.ToString ());
	}

	[Fact]
	public void Standard_Keys_Always_New ()
	{
		// Make two local keys, and grab Key.A, which is a reference to a singleton.
		var aKey1 = Key.A;
		var aKey2 = Key.A;

		// Assert the starting state that is expected
		Assert.False (aKey1.Handled);
		Assert.False (aKey2.Handled);
		Assert.False (Key.A.Handled);

		// Now set Handled true on one of our local keys
		aKey1.Handled = true;

		// Assert the newly-expected case
		// The last two assertions will fail, because we have actually modified a singleton
		Assert.True (aKey1.Handled);
		Assert.False (aKey2.Handled);
		Assert.False (Key.A.Handled);
	}

	[Theory]
	[InlineData ((KeyCode)'a',                     true)]
	[InlineData ((KeyCode)'a' | KeyCode.ShiftMask, true)]
	[InlineData (KeyCode.A,                        true)]
	[InlineData (KeyCode.A | KeyCode.ShiftMask,    true)]
	[InlineData (KeyCode.F,                        true)]
	[InlineData (KeyCode.F | KeyCode.ShiftMask,    true)]
	// these have alt or ctrl modifiers or are not a..z
	[InlineData (KeyCode.A | KeyCode.CtrlMask, false)]
	[InlineData (KeyCode.A | KeyCode.AltMask,  false)]
	[InlineData (KeyCode.D0,                   false)]
	[InlineData (KeyCode.Esc,                  false)]
	[InlineData (KeyCode.Tab,                  false)]
	public void IsKeyCodeAtoZ (KeyCode key, bool expected)
	{
		var eventArgs = new Key (key);
		Assert.Equal (expected, eventArgs.IsKeyCodeAtoZ);
	}

	[Theory]
	[InlineData ((KeyCode)'❿',                                                          '❿')]
	[InlineData ((KeyCode)'☑',                                                          '☑')]
	[InlineData ((KeyCode)'英',                                                          '英')]
	[InlineData ((KeyCode)'{',                                                          '{')]
	[InlineData ((KeyCode)'\'',                                                         '\'')]
	[InlineData ((KeyCode)'\r',                                                         '\r')]
	[InlineData ((KeyCode)'ó',                                                          'ó')]
	[InlineData ((KeyCode)'ó' | KeyCode.ShiftMask,                                      'ó')]
	[InlineData ((KeyCode)'Ó',                                                          'Ó')]
	[InlineData ((KeyCode)'ç' | KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.CtrlMask, '\0')]
	[InlineData ((KeyCode)'a',                                                          97)] // 97 or Key.Space | Key.A
	[InlineData ((KeyCode)'A',                                                          97)] // 65 or equivalent to Key.A, but A-Z are mapped to lower case by drivers
	//[InlineData (Key.A, 97)] // 65 equivalent to (Key)'A', but A-Z are mapped to lower case by drivers
	[InlineData (KeyCode.ShiftMask | KeyCode.A,                                      65)]
	[InlineData (KeyCode.CtrlMask | KeyCode.A,                                       '\0')]
	[InlineData (KeyCode.AltMask | KeyCode.A,                                        '\0')]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.A,                   '\0')]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.A,                    '\0')]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.A,                     '\0')]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.A, '\0')]
	[InlineData ((KeyCode)'z',                                                       'z')]
	[InlineData ((KeyCode)'Z',                                                       'z')]
	[InlineData (KeyCode.ShiftMask | KeyCode.Z,                                      'Z')]
	[InlineData ((KeyCode)'1',                                                       '1')]
	[InlineData (KeyCode.ShiftMask | KeyCode.D1,                                     '1')]
	[InlineData (KeyCode.CtrlMask | KeyCode.D1,                                      '\0')]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.D1,                  '\0')]
	[InlineData (KeyCode.F1,                                                         '\0')]
	[InlineData (KeyCode.ShiftMask | KeyCode.F1,                                     '\0')]
	[InlineData (KeyCode.CtrlMask | KeyCode.F1,                                      '\0')]
#pragma warning disable xUnit1025 // InlineData should be unique within the Theory it belongs to
	[InlineData (KeyCode.Enter, '\r')]
#pragma warning restore xUnit1025 // InlineData should be unique within the Theory it belongs to
	[InlineData (KeyCode.Tab,                                                            '\t')]
	[InlineData (KeyCode.Esc,                                                            0x1b)]
	[InlineData (KeyCode.Space,                                                          ' ')]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Enter, '\0')]
	[InlineData (KeyCode.Null,                                                           '\0')]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Null,  '\0')]
	[InlineData (KeyCode.CharMask,                                                       '\0')]
	[InlineData (KeyCode.SpecialMask,                                                    '\0')]
	public void AsRune_ShouldReturnCorrectIntValue (KeyCode key, uint expected)
	{
		var eventArgs = new Key (key);
		Assert.Equal ((Rune)expected, eventArgs.AsRune);
	}

	[Theory]
	[InlineData (KeyCode.AltMask, true)]
	[InlineData (KeyCode.A,       false)]
	public void IsAlt_ShouldReturnCorrectValue (KeyCode key, bool expected)
	{
		var eventArgs = new Key (key);
		Assert.Equal (expected, eventArgs.IsAlt);
	}

	[Fact]
	public void WithShift_ShouldReturnCorrectValue ()
	{
		var a = new Key (KeyCode.A);
		Assert.Equal (KeyCode.A | KeyCode.ShiftMask, a.WithShift);

		var CAD = Key.Delete.WithCtrl.WithAlt;
		Assert.Equal (KeyCode.Delete | KeyCode.CtrlMask | KeyCode.AltMask, CAD);
	}

	[Fact]
	public void NoShift_ShouldReturnCorrectValue ()
	{
		var CAD = Key.Delete.WithCtrl.WithAlt;
		Assert.Equal (KeyCode.Delete | KeyCode.CtrlMask | KeyCode.AltMask, CAD);

		Assert.Equal (KeyCode.Delete | KeyCode.AltMask, CAD.NoCtrl);

		var a = new Key (KeyCode.A).WithCtrl.WithAlt.WithShift;
		Assert.Equal (KeyCode.A, a.NoCtrl.NoShift.NoAlt);
		Assert.Equal (KeyCode.A, a.NoAlt.NoShift.NoCtrl);
		Assert.Equal (KeyCode.A, a.NoAlt.NoShift.NoCtrl.NoCtrl.NoAlt.NoShift);

		Assert.Equal (Key.Delete, Key.Delete.WithCtrl.NoCtrl);

		Assert.Equal ((KeyCode)Key.Delete | KeyCode.CtrlMask, Key.Delete.NoCtrl.WithCtrl);
	}

	[Fact]
	public void Standard_Keys_Should_Equal_KeyCode ()
	{
		Assert.Equal (KeyCode.A,      Key.A);
		Assert.Equal (KeyCode.Delete, Key.Delete);
	}

	// TODO: Create equality operator for KeyCode
	//Assert.Equal (KeyCode.DeleteChar, Key.Delete);

	// Similar tests for IsShift and IsCtrl
	[Fact]
	public void ToString_ShouldReturnReadableString ()
	{
		var eventArgs = new Key (KeyCode.CtrlMask | KeyCode.A);
		Assert.Equal ("Ctrl+A", eventArgs.ToString ());
	}

	[Theory]
	[InlineData (KeyCode.CtrlMask | KeyCode.A, '+', "Ctrl+A")]
	[InlineData (KeyCode.AltMask | KeyCode.B,  '-', "Alt-B")]
	public void ToStringWithSeparator_ShouldReturnFormattedString (KeyCode key, char separator, string expected) => Assert.Equal (expected, Key.ToString (key, (Rune)separator));

	[Theory]
	[InlineData ((KeyCode)'☑',                                                              "☑")]
	[InlineData ((KeyCode)'英',                                                              "英")]
	[InlineData ((KeyCode)'{',                                                              "{")]
	[InlineData ((KeyCode)'\'',                                                             "\'")]
	[InlineData ((KeyCode)'ó',                                                              "ó")]
	[InlineData ((KeyCode)'Ó' | KeyCode.ShiftMask,                                          "Shift+Ó")] // TODO: This is not correct, it should be Shift+ó or just Ó
	[InlineData ((KeyCode)'Ó',                                                              "Ó")]
	[InlineData ((KeyCode)'ç' | KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.CtrlMask,     "Ctrl+Alt+Shift+ç")]
	[InlineData ((KeyCode)'a',                                                              "a")] // 97 or Key.Space | Key.A
	[InlineData ((KeyCode)'A',                                                              "a")] // 65 or equivalent to Key.A, but A-Z are mapped to lower case by drivers
	[InlineData (KeyCode.ShiftMask | KeyCode.A,                                             "A")]
	[InlineData ((KeyCode)'a' | KeyCode.ShiftMask,                                          "A")]
	[InlineData (KeyCode.CtrlMask | KeyCode.A,                                              "Ctrl+A")]
	[InlineData (KeyCode.AltMask | KeyCode.A,                                               "Alt+A")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.A,                          "Ctrl+Shift+A")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.A,                           "Alt+Shift+A")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.A,                            "Ctrl+Alt+A")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.A,        "Ctrl+Alt+Shift+A")]
	[InlineData (KeyCode.ShiftMask | KeyCode.Z,                                             "Z")]
	[InlineData (KeyCode.CtrlMask | KeyCode.Z,                                              "Ctrl+Z")]
	[InlineData (KeyCode.AltMask | KeyCode.Z,                                               "Alt+Z")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.Z,                          "Ctrl+Shift+Z")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.Z,                           "Alt+Shift+Z")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.Z,                            "Ctrl+Alt+Z")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Z,        "Ctrl+Alt+Shift+Z")]
	[InlineData ((KeyCode)'1',                                                              "1")]
	[InlineData (KeyCode.ShiftMask | KeyCode.D1,                                            "Shift+1")]
	[InlineData (KeyCode.CtrlMask | KeyCode.D1,                                             "Ctrl+1")]
	[InlineData (KeyCode.AltMask | KeyCode.D1,                                              "Alt+1")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.D1,                         "Ctrl+Shift+1")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.D1,                          "Alt+Shift+1")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.D1,                           "Ctrl+Alt+1")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.D1,       "Ctrl+Alt+Shift+1")]
	[InlineData (KeyCode.F1,                                                                "F1")]
	[InlineData (KeyCode.ShiftMask | KeyCode.F1,                                            "Shift+F1")]
	[InlineData (KeyCode.CtrlMask | KeyCode.F1,                                             "Ctrl+F1")]
	[InlineData (KeyCode.AltMask | KeyCode.F1,                                              "Alt+F1")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.F1,                         "Ctrl+Shift+F1")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.F1,                          "Alt+Shift+F1")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.F1,                           "Ctrl+Alt+F1")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.F1,       "Ctrl+Alt+Shift+F1")]
	[InlineData (KeyCode.Enter,                                                             "Enter")]
	[InlineData (KeyCode.ShiftMask | KeyCode.Enter,                                         "Shift+Enter")]
	[InlineData (KeyCode.CtrlMask | KeyCode.Enter,                                          "Ctrl+Enter")]
	[InlineData (KeyCode.AltMask | KeyCode.Enter,                                           "Alt+Enter")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.Enter,                      "Ctrl+Shift+Enter")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.Enter,                       "Alt+Shift+Enter")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.Enter,                        "Ctrl+Alt+Enter")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Enter,    "Ctrl+Alt+Shift+Enter")]
	[InlineData (KeyCode.Delete,                                                            "Delete")]
	[InlineData (KeyCode.ShiftMask | KeyCode.Delete,                                        "Shift+Delete")]
	[InlineData (KeyCode.CtrlMask | KeyCode.Delete,                                         "Ctrl+Delete")]
	[InlineData (KeyCode.AltMask | KeyCode.Delete,                                          "Alt+Delete")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.Delete,                     "Ctrl+Shift+Delete")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.Delete,                      "Alt+Shift+Delete")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.Delete,                       "Ctrl+Alt+Delete")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Delete,   "Ctrl+Alt+Shift+Delete")]
	[InlineData (KeyCode.CursorUp,                                                          "CursorUp")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CursorUp,                                      "Shift+CursorUp")]
	[InlineData (KeyCode.CtrlMask | KeyCode.CursorUp,                                       "Ctrl+CursorUp")]
	[InlineData (KeyCode.AltMask | KeyCode.CursorUp,                                        "Alt+CursorUp")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.CursorUp,                   "Ctrl+Shift+CursorUp")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.CursorUp,                    "Alt+Shift+CursorUp")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.CursorUp,                     "Ctrl+Alt+CursorUp")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.CursorUp, "Ctrl+Alt+Shift+CursorUp")]
	[InlineData (KeyCode.Space,                                                             "Space")]
	[InlineData (KeyCode.Null,                                                              "Null")]
	[InlineData (KeyCode.ShiftMask | KeyCode.Null,                                          "Shift")]
	[InlineData (KeyCode.CtrlMask | KeyCode.Null,                                           "Ctrl")]
	[InlineData (KeyCode.AltMask | KeyCode.Null,                                            "Alt")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.Null,                       "Ctrl+Shift")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.Null,                        "Alt+Shift")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask | KeyCode.Null,                         "Ctrl+Alt")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Null,     "Ctrl+Alt+Shift")]
#pragma warning disable xUnit1025 // InlineData should be unique within the Theory it belongs to
	[InlineData (KeyCode.ShiftMask,                                      "Shift")]
	[InlineData (KeyCode.CtrlMask,                                       "Ctrl")]
	[InlineData (KeyCode.AltMask,                                        "Alt")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask,                   "Ctrl+Shift")]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask,                    "Alt+Shift")]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask,                     "Ctrl+Alt")]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask, "Ctrl+Alt+Shift")]
#pragma warning restore xUnit1025 // InlineData should be unique within the Theory it belongs to
	[InlineData (KeyCode.CharMask,                                    "CharMask")]
	[InlineData (KeyCode.SpecialMask,                                 "Ctrl+Alt+Shift")]
	[InlineData ((KeyCode)'+',                                        "+")]
	[InlineData ((KeyCode)'+' | KeyCode.ShiftMask,                    "Shift++")]
	[InlineData ((KeyCode)'+' | KeyCode.CtrlMask,                     "Ctrl++")]
	[InlineData ((KeyCode)'+' | KeyCode.ShiftMask | KeyCode.CtrlMask, "Ctrl+Shift++")]
	public void ToString_ShouldReturnFormattedString (KeyCode key, string expected) => Assert.Equal (expected, Key.ToString (key));

	// TryParse
	[Theory]
	[InlineData ("a",                       KeyCode.A)]
	[InlineData ("Ctrl+A",                  KeyCode.A | KeyCode.CtrlMask)]
	[InlineData ("Alt+A",                   KeyCode.A | KeyCode.AltMask)]
	[InlineData ("Shift+A",                 KeyCode.A | KeyCode.ShiftMask)]
	[InlineData ("A",                       KeyCode.A | KeyCode.ShiftMask)]
	[InlineData ("â",                       (KeyCode)'â')]
	[InlineData ("Shift+â",                 (KeyCode)'â' | KeyCode.ShiftMask)]
	[InlineData ("Shift+Â",                 (KeyCode)'Â' | KeyCode.ShiftMask)]
	[InlineData ("Ctrl+Shift+CursorUp",     KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.CursorUp)]
	[InlineData ("Ctrl+Alt+Shift+CursorUp", KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.CursorUp)]
	[InlineData ("ctrl+alt+shift+cursorup", KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.CursorUp)]
	[InlineData ("CTRL+ALT+SHIFT+CURSORUP", KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.CursorUp)]
	[InlineData ("Ctrl+Alt+Shift+Delete",   KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Delete)]
	[InlineData ("Ctrl+Alt+Shift+Enter",    KeyCode.ShiftMask | KeyCode.CtrlMask | KeyCode.AltMask | KeyCode.Enter)]
	[InlineData ("Tab",                     KeyCode.Tab)]
	[InlineData ("Shift+Tab",               KeyCode.Tab | KeyCode.ShiftMask)]
	[InlineData ("Ctrl+Tab",                KeyCode.Tab | KeyCode.CtrlMask)]
	[InlineData ("Alt+Tab",                 KeyCode.Tab | KeyCode.AltMask)]
	[InlineData ("Ctrl+Shift+Tab",          KeyCode.Tab | KeyCode.ShiftMask | KeyCode.CtrlMask)]
	[InlineData ("Ctrl+Alt+Tab",            KeyCode.Tab | KeyCode.AltMask | KeyCode.CtrlMask)]
	[InlineData ("",                        KeyCode.Null)]
	[InlineData (" ",                       KeyCode.Space)]
	[InlineData ("Space",                   KeyCode.Space)]
	[InlineData ("Shift+Space",             KeyCode.Space | KeyCode.ShiftMask)]
	[InlineData ("Ctrl+Space",              KeyCode.Space | KeyCode.CtrlMask)]
	[InlineData ("Alt+Space",               KeyCode.Space | KeyCode.AltMask)]
	[InlineData ("Shift+ ",                 KeyCode.Space | KeyCode.ShiftMask)]
	[InlineData ("Ctrl+ ",                  KeyCode.Space | KeyCode.CtrlMask)]
	[InlineData ("Alt+ ",                   KeyCode.Space | KeyCode.AltMask)]
	[InlineData ("F1",                      KeyCode.F1)]
	[InlineData ("0",                       KeyCode.D0)]
	[InlineData ("9",                       KeyCode.D9)]
	[InlineData ("D0",                      KeyCode.D0)]
	[InlineData ("65",                      KeyCode.A | KeyCode.ShiftMask)]
	[InlineData ("97",                      KeyCode.A)]
	[InlineData ("Shift",                   KeyCode.ShiftMask)]
	[InlineData ("Ctrl",                    KeyCode.CtrlMask)]
	[InlineData ("Ctrl-A",                  KeyCode.A | KeyCode.CtrlMask)]
	[InlineData ("Alt-A",                   KeyCode.A | KeyCode.AltMask)]
	[InlineData ("A-Ctrl",                  KeyCode.A | KeyCode.CtrlMask)]
	[InlineData ("Alt-A-Ctrl",              KeyCode.A | KeyCode.CtrlMask | KeyCode.AltMask)]
	public void TryParse_ShouldReturnTrue_WhenValidKey (string keyString, KeyCode expected)
	{
		Assert.True (Key.TryParse (keyString, out var key));
		Key expectedKey = expected;
		Assert.Equal (expectedKey.ToString (), key.ToString ());
	}

	[Theory]
	[InlineData ("aa")]
	[InlineData ("-1")]
	[InlineData ("Crtl-A")]
	[InlineData ("Ctrl=A")]
	[InlineData ("Crtl")]
	[InlineData ("99a")]
	[InlineData ("a99")]
	[InlineData ("#99")]
	[InlineData ("x99")]
	[InlineData ("0x99")]
	[InlineData ("Ctrl-Ctrl")]
	public void TryParse_ShouldReturnFalse_On_InvalidKey (string keyString) => Assert.False (Key.TryParse (keyString, out var _));

	[Theory]
	[InlineData (KeyCode.ShiftMask,                                      true,  false, false)]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask,                    true,  true,  false)]
	[InlineData (KeyCode.ShiftMask | KeyCode.AltMask | KeyCode.CtrlMask, true,  true,  true)]
	[InlineData (KeyCode.ShiftMask | KeyCode.CtrlMask,                   true,  false, true)]
	[InlineData (KeyCode.AltMask,                                        false, true,  false)]
	[InlineData (KeyCode.AltMask | KeyCode.CtrlMask,                     false, true,  true)]
	[InlineData (KeyCode.CtrlMask,                                       false, false, true)]
	public void IsShift_IsAlt_IsCtrl (KeyCode keyCode, bool isShift, bool isAlt, bool isCtrl)
	{
		Assert.Equal (((Key)keyCode).IsShift, isShift);
		Assert.Equal (((Key)keyCode).IsAlt,   isAlt);
		Assert.Equal (((Key)keyCode).IsCtrl,  isCtrl);
	}

	[Theory]
	[InlineData (KeyCode.A,  KeyCode.A)]
	[InlineData (KeyCode.F1, KeyCode.F1)]
	public void Casting_Between_Key_And_KeyCode (KeyCode keyCode, KeyCode key)
	{
		Assert.Equal (keyCode, (Key)key);
		Assert.NotEqual (keyCode, ((Key)key).WithShift);
		Assert.Equal ((uint)keyCode, (uint)(Key)key);
		Assert.NotEqual ((uint)keyCode, (uint)((Key)key).WithShift);
	}
}