read-only HID++ case capture unexpectedly opened a raw…

Error message

read-only HID++ case capture unexpectedly opened a raw writer; no fixture was written

What it means

`sanitize_recording_with_plan` audits the captured recording and asserts a read-only HID++ case capture never opened a raw writer. If the audit finds raw-writer activity recorded during the capture, the recording cannot be a valid read-only fixture and the error aborts before writing anything.

Solutions

Record the case with the correct operation kind (a writable case) rather than declaring it read-only
Pick a genuinely read-only operation for this capture (feature enumeration, config reads)
If you believe the operation is read-only but the device emits a write, file/inspect the operation catalog entry in openlogi-core for a misclassification

Example fix

// before (write-typed op recorded as read-only case)
record_case(Operation::SetDpi, read_only: true)
// after
record_case(Operation::SetDpi, read_only: false)
// or choose a read-only op:
record_case(Operation::GetDpi, read_only: true)

Defensive patterns

Strategy: validation

Validate before calling

// confirm the operation is genuinely read-only before a read-only capture
assert!(operation_catalog.is_read_only(op), "op {op:?} writes to the device; do not record as read-only");

Try / catch

if err.to_string().contains("unexpectedly opened a raw writer") {
    eprintln!("operation writes to the device; record as a writable case instead");
}

Prevention

Keep the operation catalog's read/write classification accurate
Only mark captures read-only for pure query operations
Never hand-edit fixture audit data that toggles capture kind

When it happens

Trigger: A capture declared as read-only HID++ recorded raw HID output reports (raw writer opens) — e.g. the operation touched a write-only/raw path instead of a pure HID++ read, or the capture logic misclassified a write operation as read-only.

Common situations: Recording a case whose operation actually writes to the device (DPI write, profile set) while the case is declared read-only; a firmware/device where a nominally read command triggers an output report; a bug in the operation catalog tagging an operation read-only incorrectly.

Understand the failure class

Background: "This is a bug, please report it": internal invariant violations, unreachable panics, and SNH errors explained — this error's family across 47 libraries.

Related errors

AI-assisted analysis of AprilNEA/OpenLogi@e846e6f4b4 (2026-09-13). Data as JSON: /api/errors/11eef8d7215229c9. Report an issue: GitHub.

Appendix: source

Thrown at crates/openlogi-cli/src/cmd/fixture/record_case/audit.rs:40

                name: name.to_string(),
                channel: channel.to_string(),
            },
            identity_plan,
        );
        render_build_report(index, &report);
        if report.rejections.is_empty()
            && let Some(cassette) = report.cassette.clone()
        {
            candidates.push(SanitizedCandidate {
                cassette,
                audit: report.audit,
            });
        }
    }
    drop(recording);

    if recorded_raw_writers {
        bail!(
            "read-only HID++ case capture unexpectedly opened a raw writer; no fixture was written"
        );
    }
    Ok(candidates)
}

fn render_build_report(index: usize, report: &HidCassetteBuildReport) {
    if report.is_committable() {
        eprintln!("channel candidate {}: sanitizer accepted", index + 1);
    } else {
        eprintln!("channel candidate {}: sanitizer rejected", index + 1);
    }
    for replacement in &report.audit.replacements {
        eprintln!(
            "  audit: {} replaced {} occurrence(s) with synthetic {}",
            identity_kind_label(replacement.kind),
            replacement.occurrences,
            uppercase_hex(&replacement.synthetic_value)

View on GitHub (pinned to e846e6f4b4)