Allow to extend the client, make initialize params and request protected?

[krassowski]

This library would be a bit more useful if it allowed to configure language servers or otherwise extend its functionality.

Currently it is not possible to cleanly override the behaviour of the LanguageServerClient because:

• the initialize options are hard-coded in initialize() method; while this method is public and can be overridden by copy-pasting,
• the request is marked as private which means that we need to use @ts-ignore

Would you consider a PR which:

• changes request to protected so that it can be used in subclasses
  

  codemirror-languageserver/src/index.ts

  Line 219 in d8c88a4

  private request<K extends keyof LSPRequestMap>(

• moves the hard-coded initialize options to a protected method?
  

  codemirror-languageserver/src/index.ts

  Lines 123 to 182 in d8c88a4

  	public async initialize() {
  	const { capabilities } = await this.request("initialize", {
  	capabilities: {
  	textDocument: {
  	hover: {
  	dynamicRegistration: true,
  	contentFormat: ["plaintext", "markdown"],
  	},
  	moniker: {},
  	synchronization: {
  	dynamicRegistration: true,
  	willSave: false,
  	didSave: false,
  	willSaveWaitUntil: false,
  	},
  	completion: {
  	dynamicRegistration: true,
  	completionItem: {
  	snippetSupport: false,
  	commitCharactersSupport: true,
  	documentationFormat: ["plaintext", "markdown"],
  	deprecatedSupport: false,
  	preselectSupport: false,
  	},
  	contextSupport: false,
  	},
  	signatureHelp: {
  	dynamicRegistration: true,
  	signatureInformation: {
  	documentationFormat: ["plaintext", "markdown"],
  	},
  	},
  	declaration: {
  	dynamicRegistration: true,
  	linkSupport: true,
  	},
  	definition: {
  	dynamicRegistration: true,
  	linkSupport: true,
  	},
  	typeDefinition: {
  	dynamicRegistration: true,
  	linkSupport: true,
  	},
  	implementation: {
  	dynamicRegistration: true,
  	linkSupport: true,
  	},
  	},
  	workspace: {
  	didChangeConfiguration: {
  	dynamicRegistration: true,
  	},
  	},
  	},
  	initializationOptions: null,
  	processId: null,
  	rootUri: this.rootUri,
  	workspaceFolders: this.workspaceFolders,
  	}, timeout * 3);

[krassowski]

The same would apply to access to notify method :)