Function createPlugin

src/cm/lsp/inlayHints.ts:135–274

(config: InlayHintsConfig)

// ============================================================================

function createPlugin(config: InlayHintsConfig) {
	const delay = config.debounceMs ?? 200;
	const max = config.maxHints ?? 500;
	const showTypes = config.showTypes !== false;
	const showParams = config.showParameters !== false;

	return ViewPlugin.fromClass(
		class {
			decorations: DecorationSet = Decoration.none;
			timer: ReturnType<typeof setTimeout> | null = null;
			reqId = 0;

			constructor(private view: EditorView) {
				this.fetch();
			}

			update(update: ViewUpdate): void {
				if (
					update.transactions.some((t) => t.effects.some((e) => e.is(setHints)))
				) {
					this.decorations = buildDecos(
						update.state.field(hintsField, false) ?? [],
						update.state.doc.length,
					);
				}
				if (update.docChanged || update.viewportChanged) {
					this.schedule();
				}
			}

			schedule(): void {
				if (this.timer) clearTimeout(this.timer);
				this.timer = setTimeout(() => {
					this.timer = null;
					this.fetch();
				}, delay);
			}

			async fetch(): Promise<void> {
				const lsp = LSPPlugin.get(this.view) as LSPPluginAPI | null;
				if (!lsp?.client.connected) return;

				const caps = lsp.client.serverCapabilities;
				if (!caps?.inlayHintProvider) return;

				lsp.client.sync();
				const id = ++this.reqId;
				const doc = this.view.state.doc;

				// Visible range with buffer
				const { from, to } = this.view.viewport;
				const buf = 20;
				const startLn = Math.max(1, doc.lineAt(Math.max(0, from)).number - buf);
				const endLn = Math.min(
					doc.lines,
					doc.lineAt(Math.min(doc.length, to)).number + buf,
				);