private async pullAsync()

in client/src/common/proposed.diagnostic.ts [309:366]
55 lines of code
17 McCabe index (conditional complexity)

	private async pullAsync(textDocument: TextDocument): Promise<void> {
		const key = textDocument.uri.toString();
		const version = textDocument.version;
		const currentRequestState = this.openRequests.get(key);
		const documentState = this.documentStates.track(PullState.document, textDocument);
		if (currentRequestState === undefined) {
			const tokenSource = new CancellationTokenSource();
			this.openRequests.set(key, { state: RequestStateKind.active, version: version, textDocument, tokenSource });
			let report: vsdiag.DocumentDiagnosticReport | undefined;
			let afterState: RequestState | undefined;
			try {
				report = await this.provider.provideDiagnostics(textDocument, documentState.resultId, tokenSource.token) ?? { kind: vsdiag.DocumentDiagnosticReportKind.full, items: [] };
			} catch (error) {
				if (error instanceof LSPCancellationError && Proposed.DiagnosticServerCancellationData.is(error.data) && error.data.retriggerRequest === false) {
					afterState = { state: RequestStateKind.outDated, textDocument };
				}
				if (afterState === undefined && error instanceof CancellationError) {
					afterState = { state: RequestStateKind.reschedule, textDocument };
				} else {
					throw error;
				}
			}
			afterState = afterState ?? this.openRequests.get(key);
			if (afterState === undefined) {
				// This shouldn't happen. Log it
				this.client.error(`Lost request state in diagnostic pull model. Clearing diagnostics for ${key}`);
				this.diagnostics.delete(textDocument.uri);
				return;
			}
			this.openRequests.delete(key);
			if (!this.editorTracker.isVisible(textDocument)) {
				this.documentStates.unTrack(PullState.document, textDocument);
				return;
			}
			if (afterState.state === RequestStateKind.outDated) {
				return;
			}
			// report is only undefined if the request has thrown.
			if (report !== undefined) {
				if (report.kind === vsdiag.DocumentDiagnosticReportKind.full) {
					this.diagnostics.set(textDocument.uri, report.items);
				}
				documentState.pulledVersion = version;
				documentState.resultId = report.resultId;
			}
			if (afterState.state === RequestStateKind.reschedule) {
				this.pull(textDocument);
			}
		} else {
			if (currentRequestState.state === RequestStateKind.active) {
				// Cancel the current request and reschedule a new one when the old one returned.
				currentRequestState.tokenSource.cancel();
				this.openRequests.set(key, { state: RequestStateKind.reschedule, textDocument: currentRequestState.textDocument });
			} else if (currentRequestState.state === RequestStateKind.outDated) {
				this.openRequests.set(key, { state: RequestStateKind.reschedule, textDocument: currentRequestState.textDocument });
			}
		}
	}