Function run_completion

tests/fixture_runner.rs:405–468

(fixture: &ParsedFixture)

// ─── Feature runners ────────────────────────────────────────────────────────

async fn run_completion(fixture: &ParsedFixture) -> Result<(), String> {
    let backend = create_fixture_backend();
    let uri = open_files(&backend, fixture).await;

    let position = Position {
        line: fixture.cursor_line,
        character: fixture.cursor_char,
    };

    let params = CompletionParams {
        text_document_position: TextDocumentPositionParams {
            text_document: TextDocumentIdentifier { uri },
            position,
        },
        work_done_progress_params: WorkDoneProgressParams::default(),
        partial_result_params: PartialResultParams::default(),
        context: None,
    };

    let response = backend
        .completion(params)
        .await
        .map_err(|e| format!("Completion request failed: {e}"))?;

    let items = match response {
        Some(CompletionResponse::Array(items)) => items,
        Some(CompletionResponse::List(list)) => list.items,
        None => Vec::new(),
    };

    let labels: Vec<String> = items.iter().map(|item| item.label.clone()).collect();

    // Check expected items are present.
    for expected in &fixture.meta.expect {
        let found = labels
            .iter()
            .any(|label| label.starts_with(expected.as_str()));
        if !found {
            return Err(format!(
                "Expected completion label starting with `{expected}` not found.\nGot: {labels:?}"
            ));
        }
    }

    // Check absent items are not present.
    for absent in &fixture.meta.expect_absent {
        let found = labels
            .iter()
            .any(|label| label.starts_with(absent.as_str()));
        if found {
            return Err(format!(
                "Completion label starting with `{absent}` should NOT be present.\nGot: {labels:?}"
            ));
        }
    }

    if fixture.meta.expect.is_empty() && fixture.meta.expect_absent.is_empty() {
        return Err(