src/vs/workbench/common/editor/sideBySideEditorInput.ts/SideBySideEditorInput/rename
class SideBySideEditorInput:	override async rename(group: GroupIdentifier, target: URI): Promise<IMoveResult | undefined> {
		if (!this.hasIdenticalSides) {
			return; // currently only enabled when both sides are identical
		}

		// Forward rename to primary side
		const renameResult = await this.primary.rename(group, target);
		if (!renameResult) {
			return undefined;
		}

		// Build a side-by-side result from the rename result

		if (isEditorInput(renameResult.editor)) {
			return {
				editor: new SideBySideEditorInput(this.preferredName, this.preferredDescription, renameResult.editor, renameResult.editor, this.editorService),
				options: {
					...renameResult.options,
					viewState: findViewStateForEditor(this, group, this.editorService)
				}
			};
		}

		if (isResourceEditorInput(renameResult.editor)) {
			return {
				editor: {
					label: this.preferredName,
					description: this.preferredDescription,
					primary: renameResult.editor,
					secondary: renameResult.editor,
					options: {
						...renameResult.options,
						viewState: findViewStateForEditor(this, group, this.editorService)
					}
				}
			};
		}

		return undefined;
	}