pola-rs/polars · error

activate 'timezones' feature

Error message

activate 'timezones' feature

What it means

When parsing a string ChunkedArray into a Datetime, if the inferred format indicates a timezone offset the code paths under cfg(feature = "timezones") construct a timezone-aware Datetime; with the feature compiled out, the library explicitly panics to say timezone support is missing.

Solutions

1. Enable the 'timezones' feature in Cargo.toml: polars = { version = "...", features = ["timezones", "temporal"] }.
2. Strip the timezone suffix from strings before parsing and parse as naive Datetime.
3. Parse as Datetime with an explicit format that excludes the offset, or cast to Date instead.
4. If offsets must be honored, upgrade to a build with 'timezones' (default feature of the full polars meta-crate).

Example fix

// before
polars = { version = "0.40", default-features = false, features = ["lazy", "temporal"] }
// after
polars = { version = "0.40", default-features = false, features = ["lazy", "temporal", "timezones"] }

// detect tz offsets in the strings you will parse
let has_tz = string_series.str()?.contains("(Z|[+-]\d{2}:?\d{2})$")?;
if has_tz && !cfg!(feature = "timezones") { /* strip offsets or enable feature */ }

When it happens

Trigger: Calling str.to_datetime(...) / cast from String to Datetime on strings containing a timezone offset (e.g. '2024-01-01T00:00:00+02:00') while polars was built without the 'timezones' feature.

Common situations: Using the default polars crate features (or the slim polars-core) when your data includes ISO timestamps with 'Z' or '+hh:mm' offsets; CI images built with a reduced feature set.

Related errors

• activate 'timezones' feature
• expected index type found
• activate 'decompress' feature
• activate dtype
• activate dtype-categorical to convert dictionary arrays

AI-assisted analysis of pola-rs/polars@fe841f959e (2026-09-18). Data as JSON: /api/errors/cc2b25de07ad9d51. Report an issue: GitHub.

Appendix: source

Thrown at crates/polars-core/src/chunked_array/temporal/string/mod.rs:291

        if tz_aware {
            #[cfg(feature = "timezones")]
            {
                let mut convert = LruCachedFunc::new(
                    |s: &str| {
                        let dt = DateTime::parse_from_str(s, &fmt).ok()?;
                        Some(func(dt.naive_utc()))
                    },
                    (string_ca.len() as f64).sqrt() as usize,
                );
                Ok(
                    unary_elementwise(string_ca, |opt_s| convert.eval(opt_s?, use_cache))
                        .with_name(string_ca.name().clone())
                        .into_datetime(tu, Some(tz.cloned().unwrap_or(TimeZone::UTC))),
                )
            }
            #[cfg(not(feature = "timezones"))]
            {
                panic!("activate 'timezones' feature")
            }
        } else {
            let transform = match tu {
                TimeUnit::Nanoseconds => infer::transform_datetime_ns,
                TimeUnit::Microseconds => infer::transform_datetime_us,
                TimeUnit::Milliseconds => infer::transform_datetime_ms,
            };
            let ca = if strptime::fast_parser_supported(fmt.as_bytes()) {
                let mut strptime_cache = StrpTimeState::default();
                let mut convert = LruCachedFunc::new(
                    |s: &str| match strptime_cache.parse(s.as_bytes(), fmt.as_bytes()) {
                        None => transform(s, &fmt),
                        Some(ndt) => Some(func(ndt)),
                    },
                    (string_ca.len() as f64).sqrt() as usize,
                );
                unary_elementwise(string_ca, |opt_s| convert.eval(opt_s?, use_cache))
            } else {

View on GitHub (pinned to fe841f959e)