Support for linting on change.

[alkatar21]

The inline hints that highlight problems in the code do not behave as expected on unsaved files. While pylance/pyright move the hints, the pylint problem hints do not.

I'm not quite sure if it's more of a bug or a feature request?

Since I do not know how best to create a gif here at least 2 images (The red lines are pylance and the blue and yellow one are from pylint.):

[karthiknadig]

@alkatar21 Changing this to a feature request. What we need here is to support linting on change.

Currently, we support linting on open, save and clean up on close, we will need to add on change support here:

vscode-pylint/bundled/linter/linter_server.py

Lines 211 to 228 in 68fe00b

	@LSP_SERVER.feature(lsp.TEXT_DOCUMENT_DID_OPEN)
	def did_open(_server: server.LanguageServer, params: types.DidOpenTextDocumentParams):
	"""LSP handler for textDocument/didOpen request."""
	_lint_and_publish_diagnostics(params)
	@LSP_SERVER.feature(lsp.TEXT_DOCUMENT_DID_SAVE)
	def did_save(_server: server.LanguageServer, params: types.DidSaveTextDocumentParams):
	"""LSP handler for textDocument/didSave request."""
	_lint_and_publish_diagnostics(params)
	@LSP_SERVER.feature(lsp.TEXT_DOCUMENT_DID_CLOSE)
	def did_close(_server: server.LanguageServer, params: types.DidCloseTextDocumentParams):
	"""LSP handler for textDocument/didClose request."""
	# Publishing empty diagnostics to clear the entries for this file.
	text_document = LSP_SERVER.workspace.get_document(params.text_document.uri)
	LSP_SERVER.publish_diagnostics(text_document.uri, [])

A caveat with supporting on change is we may also have to support cancel request. Users may also want the ability to turnoff linting on change.

/cc @luabud

[luabud]

Related to microsoft/vscode-python#408

[karthiknadig]

If we do this, it should be put behind pylint.lintOnChange setting scoped to the machine level. Propagate that setting in settings.ts.

Registration in LSP itself can be done in initialize in linter_server.py:

if setting["lintOnChange"]:
    @LSP_SERVER.feature(lsp.TEXT_DOCUMENT_DID_CHANGE) 
    def did_change(_server: server.LanguageServer, params: types.DidSaveTextDocumentParams): 
        """LSP handler for textDocument/didChange request.""" 
        _lint_and_publish_diagnostics(params) 

[karthiknadig]

Closed via #368

[luabud]

verified: