Initial LSP implementation/vscode support

newt-vscode-lsp/src/lsp.ts

@@ -0,0 +1,53 @@
+/**
+ * WIP
+ *
+ * Wraps newt.js (compiled from src/LSP.newt with some tweaks to `export`) with the
+ * vscode LSP server module.
+ */
+
+import { LSP_checkFile, LSP_updateFile, LSP_hoverInfo } from './newt.js'
+
+import {
+  createConnection,
+  TextDocuments,
+  ProposedFeatures,
+  Hover,
+  InitializeParams,
+  InitializeResult,
+  TextDocumentSyncKind,
+} from "vscode-languageserver/node";
+import { TextDocument } from "vscode-languageserver-textdocument";
+
+const connection = createConnection(ProposedFeatures.all);
+const documents = new TextDocuments(TextDocument);
+
+documents.onDidChangeContent(async (change) => {
+  console.log('DIDCHANGE', change.document.uri)
+  const uri = change.document.uri;
+  const text = change.document.getText();
+  LSP_updateFile(uri, text);
+  const diagnostics = LSP_checkFile(uri);
+  console.log(`Got ${JSON.stringify(diagnostics, null, '  ')}`)
+  connection.sendDiagnostics({ uri, diagnostics })
+});
+
+connection.onHover((params): Hover | null => {
+  const uri = params.textDocument.uri;
+  const pos = params.position;
+  console.log('HOVER', uri, pos)
+  let value = LSP_hoverInfo(uri, pos.line, pos.character)
+  if (!value) return null
+  console.log('HOVER is ', value)
+  return { contents: { kind: "plaintext", value } };
+});
+
+connection.onInitialize((_params: InitializeParams): InitializeResult => ({
+  capabilities: {
+    textDocumentSync: TextDocumentSyncKind.Incremental,
+    hoverProvider: true,
+  },
+}));
+
+documents.listen(connection);
+connection.listen();
+console.log('STARTED')