quickwit-oss/tantivy · error

unexpected type {:?}. This should not happen

Error message

unexpected type {:?}. This should not happen

What it means

In the composite aggregation's histogram source, the value-to-float conversion only handles U64, I64, DateTime and F64 column types. Any other type (Str, Bytes, Bool, IpAddr) reaching visit is an internal bug — the source was expected to be a numeric fast field — so it panics with 'unexpected type ... This should not happen'.

Source

Thrown at src/aggregation/bucket/composite/collector.rs:568

                        }
                        self.sub_level_values.push(InternalValueRepr::new_term(
                            value,
                            accessor_idx as u8,
                            current_level_source.order(),
                        ));
                        let still_on_after_key = matches_after_key_type
                            && current_level_accessors.after_key.equals(value);
                        self.visit(source_idx + 1, is_on_after_key && still_on_after_key)?;
                        self.sub_level_values.pop();
                    }
                    CompositeAggregationSource::Histogram(source) => {
                        let float_value = match accessor.column_type {
                            ColumnType::U64 => value as f64,
                            ColumnType::I64 => i64::from_u64(value) as f64,
                            ColumnType::DateTime => i64::from_u64(value) as f64 / 1_000_000.,
                            ColumnType::F64 => f64::from_u64(value),
                            _ => {
                                panic!(
                                    "unexpected type {:?}. This should not happen",
                                    accessor.column_type
                                )
                            }
                        };
                        let bucket_index = (float_value / source.interval).floor() as i64;
                        let bucket_value = i64::to_u64(bucket_index);
                        if is_on_after_key {
                            let should_skip = match current_level_source.order() {
                                Order::Asc => current_level_accessors.after_key.gt(bucket_value),
                                Order::Desc => current_level_accessors.after_key.lt(bucket_value),
                            };
                            if should_skip {
                                continue;
                            }
                        }
                        self.sub_level_values.push(InternalValueRepr::new_histogram(
                            bucket_value,

View on GitHub (pinned to b5d8deb80c)

Solutions

1. Ensure the histogram source field is a numeric or date fast field in the schema (u64/i64/f64/date).
2. Validate the aggregation request against the schema at query build time and reject non-numeric histogram sources.
3. If the schema looks correct, this is an internal accessor-resolution bug — report it with the schema and query.

Example fix

// before
CompositeAggregationSource::Histogram(h)
// after — validate before building the collector
match schema.get_field(name).map(|f| schema.get_field_entry(f).field_type()) {
    Some(t) if t.is_numeric() || matches!(t, FieldType::Date(_)) => {},
    _ => return Err(InvalidArgument("histogram source requires numeric/date field")),
}

match accessor.column_type {
    ColumnType::U64 | ColumnType::I64 | ColumnType::F64 | ColumnType::DateTime => Ok(()),
    other => Err(format!("histogram requires numeric/date, got {:?}", other)),
}

fn is_numeric_or_date(t: &ColumnType) -> bool {
    matches!(t, ColumnType::U64 | ColumnType::I64 | ColumnType::F64 | ColumnType::DateTime)
}

When it happens

Trigger: Visiting a histogram composite source whose accessor.column_type is not one of U64/I64/DateTime/F64 — e.g. the field resolved to a Str/Bytes/Bool/IpAddr fast field but was declared as a histogram (numeric) source.

Common situations: Field type mismatch between schema and aggregation request (requesting a histogram over a text/keyword field); schema migration changed a numeric field to keyword; a bug in accessor type resolution passing the wrong accessor.

Related errors

• unsupported
• interval not precomputed for date histogram source
• unsupported
• null must be handled separately
• dictionary missing for str accessor

AI-assisted analysis of quickwit-oss/tantivy@b5d8deb80c (2026-09-05). Data as JSON: /api/errors/c9f271d6eae7d177. Report an issue: GitHub.