src/vs/platform/terminal/node/windowsShellHelper.ts/WindowsShellHelper/getShellName
class WindowsShellHelper:	async getShellName(): Promise<string> {
		if (this._isDisposed) {
			return Promise.resolve('');
		}
		// Prevent multiple requests at once, instead return current request
		if (this._currentRequest) {
			return this._currentRequest;
		}
		if (!windowsProcessTree) {
			windowsProcessTree = await import('windows-process-tree');
		}
		this._currentRequest = new Promise<string>(resolve => {
			windowsProcessTree.getProcessTree(this._rootProcessId, tree => {
				const name = this.traverseTree(tree);
				this._currentRequest = undefined;
				resolve(name);
			});
		});
		return this._currentRequest;
	}