_WindowMiddleware - wrong definition for showDocument

[ljw1004]

_WindowMiddleware.showDocument request from server to client is missing a "token" parameter. Here is the definition. Observe that the "next" parameter is a function which takes (params: ShowDocumentParams, token: CancellationToken). However, showDocument itself doesn't take a token parameter. Therefore we have nothing to pass when we invoke next(param, ???needToken??).

vscode-languageserver-node/client/src/common/client.ts

Lines 294 to 296 in bafd287

	interface _WindowMiddleware {
	showDocument?: (this: void, params: ShowDocumentParams, next: ShowDocumentRequest.HandlerSignature) => Promise<ShowDocumentResult>;
	}

vscode-languageserver-node/protocol/src/common/protocol.showDocument.ts

Lines 78 to 84 in bafd287

	export namespace ShowDocumentRequest {
	export const method: 'window/showDocument' = 'window/showDocument';
	export const messageDirection: MessageDirection = MessageDirection.serverToClient;
	export const type = new ProtocolRequestType<ShowDocumentParams, ShowDocumentResult, void, void, void>(method);
	export type HandlerSignature = RequestHandler<ShowDocumentParams, ShowDocumentResult, void>;
	export type MiddlewareSignature = (params: ShowDocumentParams, next: HandlerSignature) => HandlerResult<ShowDocumentResult, void>;
	}

vscode-languageserver-node/jsonrpc/src/common/connection.ts

Lines 89 to 91 in bafd287

	export interface RequestHandler<P, R, E> {
	(params: P, token: CancellationToken): HandlerResult<R, E>;
	}

By comparison, let's look at ConfigurationMiddleware.configuration request from server to client, where the signature of configuration does correctly take a token and is therefore able to pass it to the next function.

vscode-languageserver-node/client/src/common/configuration.ts

Lines 17 to 19 in bafd287

	export interface ConfigurationMiddleware {
	configuration?: ConfigurationRequest.MiddlewareSignature;
	}

vscode-languageserver-node/protocol/src/common/protocol.configuration.ts

Lines 22 to 28 in bafd287

	export namespace ConfigurationRequest {
	export const method: 'workspace/configuration' = 'workspace/configuration';
	export const messageDirection: MessageDirection = MessageDirection.serverToClient;
	export const type = new ProtocolRequestType<ConfigurationParams, LSPAny[], never, void, void>(method);
	export type HandlerSignature = RequestHandler<ConfigurationParams, LSPAny[], void>;
	export type MiddlewareSignature = (params: ConfigurationParams, token: CancellationToken, next: HandlerSignature) => HandlerResult<LSPAny[], void>;
	}

[ljw1004]

I also think the return type of showDocument is wrong. It should allow the possibility to return error, since the next function is able to return error.

vscode-languageserver-node/jsonrpc/src/common/connection.ts

Line 69 in bafd287

export type HandlerResult<R, E> = R | ResponseError<E> | Thenable<R> | Thenable<ResponseError<E>> | Thenable<R | ResponseError<E>>;