private doInitialize()

in client/src/common/client.ts [3486:3558]
67 lines of code
14 McCabe index (conditional complexity)

	private doInitialize(connection: Connection, initParams: InitializeParams): Promise<InitializeResult> {
		return connection.initialize(initParams).then((result) => {
			this._resolvedConnection = connection;
			this._initializeResult = result;
			this.state = ClientState.Running;

			let textDocumentSyncOptions: TextDocumentSyncOptions | undefined = undefined;
			if (Is.number(result.capabilities.textDocumentSync)) {
				if (result.capabilities.textDocumentSync === TextDocumentSyncKind.None) {
					textDocumentSyncOptions = {
						openClose: false,
						change: TextDocumentSyncKind.None,
						save: undefined
					};
				} else {
					textDocumentSyncOptions = {
						openClose: true,
						change: result.capabilities.textDocumentSync,
						save: {
							includeText: false
						}
					};
				}
			} else if (result.capabilities.textDocumentSync !== undefined && result.capabilities.textDocumentSync !== null) {
				textDocumentSyncOptions = result.capabilities.textDocumentSync as TextDocumentSyncOptions;
			}
			this._capabilities = Object.assign({}, result.capabilities, { resolvedTextDocumentSync: textDocumentSyncOptions });

			connection.onDiagnostics(params => this.handleDiagnostics(params));
			connection.onRequest(RegistrationRequest.type, params => this.handleRegistrationRequest(params));
			// See https://github.com/Microsoft/vscode-languageserver-node/issues/199
			connection.onRequest('client/registerFeature', params => this.handleRegistrationRequest(params));
			connection.onRequest(UnregistrationRequest.type, params => this.handleUnregistrationRequest(params));
			// See https://github.com/Microsoft/vscode-languageserver-node/issues/199
			connection.onRequest('client/unregisterFeature', params => this.handleUnregistrationRequest(params));
			connection.onRequest(ApplyWorkspaceEditRequest.type, params => this.handleApplyWorkspaceEdit(params));

			return connection.sendNotification(InitializedNotification.type, {}).then(() => {
				this.hookFileEvents(connection);
				this.hookConfigurationChanged(connection);
				this.initializeFeatures(connection);
				this._onReadyCallbacks.resolve();
				return result;
			});

		}).then<InitializeResult>(undefined, (error: any) => {
			if (this._clientOptions.initializationFailedHandler) {
				if (this._clientOptions.initializationFailedHandler(error)) {
					void this.initialize(connection);
				} else {
					void this.stop();
					this._onReadyCallbacks.reject(error);
				}
			} else if (error instanceof ResponseError && error.data && error.data.retry) {
				void Window.showErrorMessage(error.message, { title: 'Retry', id: 'retry' }).then(item => {
					if (item && item.id === 'retry') {
						void this.initialize(connection);
					} else {
						void this.stop();
						this._onReadyCallbacks.reject(error);
					}
				});
			} else {
				if (error && error.message) {
					void Window.showErrorMessage(error.message);
				}
				this.error('Server initialization failed.', error);
				void this.stop();
				this._onReadyCallbacks.reject(error);
			}
			throw error;
		});
	}