Fixes #32568: A ResolvedKeybinding must have a first part

src/vs/platform/keybinding/common/usLayoutResolvedKeybinding.ts

@@ -21,8 +21,7 @@ export class USLayoutResolvedKeybinding extends ResolvedKeybinding {
 		super();
 		this._os = OS;
 		if (actual === null) {
-			this._firstPart = null;
-			this._chordPart = null;
+			throw new Error(`Invalid USLayoutResolvedKeybinding`);
 		} else if (actual.type === KeybindingType.Chord) {
 			this._firstPart = actual.firstPart;
 			this._chordPart = actual.chordPart;

src/vs/workbench/services/keybinding/common/macLinuxKeyboardMapper.ts

@@ -74,6 +74,9 @@ export class NativeResolvedKeybinding extends ResolvedKeybinding {
 
 	constructor(mapper: MacLinuxKeyboardMapper, OS: OperatingSystem, firstPart: ScanCodeBinding, chordPart: ScanCodeBinding) {
 		super();
+		if (!firstPart) {
+			throw new Error(`Invalid USLayoutResolvedKeybinding`);
+		}
 		this._mapper = mapper;
 		this._OS = OS;
 		this._firstPart = firstPart;

src/vs/workbench/services/keybinding/common/windowsKeyboardMapper.ts

@@ -86,6 +86,9 @@ export class WindowsNativeResolvedKeybinding extends ResolvedKeybinding {
 
 	constructor(mapper: WindowsKeyboardMapper, firstPart: SimpleKeybinding, chordPart: SimpleKeybinding) {
 		super();
+		if (!firstPart) {
+			throw new Error(`Invalid WindowsNativeResolvedKeybinding firstPart`);
+		}
 		this._mapper = mapper;
 		this._firstPart = firstPart;
 		this._chordPart = chordPart;