{"record":{"id":"0a17142bd4d54223","repo":"pola-rs/polars","slug":"no-enum-variants-on-filetype-hint-missing-featur","errorCode":null,"errorMessage":"no enum variants on FileType (hint: missing feature flags?)","messagePattern":"no enum variants on FileType \\(hint: missing feature flags\\?\\)","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"error","filePath":"crates/polars-stream/src/nodes/io_sinks/writers/mod.rs","lineNumber":111,"sourceCode":"            for dtype in file_schema.iter_values() {\n                polars_io::json::ensure_json_writable(dtype)?;\n            }\n\n            Arc::new(\n                crate::nodes::io_sinks::writers::ndjson::NDJsonWriterStarter {\n                    options: *options,\n                    schema: file_schema.clone(),\n                    initialized_state: Default::default(),\n                },\n            ) as _\n        },\n        #[cfg(not(any(\n            feature = \"parquet\",\n            feature = \"ipc\",\n            feature = \"csv\",\n            feature = \"json\"\n        )))]\n        _ => panic!(\"no enum variants on FileType (hint: missing feature flags?)\"),\n    })\n}\n","sourceCodeStart":93,"sourceCodeEnd":114,"githubUrl":"https://github.com/pola-rs/polars/blob/68506541d2de983056c9eb244e1ea05fab377dfc/crates/polars-stream/src/nodes/io_sinks/writers/mod.rs#L93-L114","documentation":"Exhausted match on FileWriteFormat in the sink-writer factory: the requested file format's writer starter is compiled out because none of the parquet/ipc/csv/json cargo features are enabled for polars-stream. It fires when creating a sink node for a format the build does not support.","triggerScenarios":"Writing a file type whose crate feature was not compiled in.","commonSituations":"See trigger scenarios.","solutions":["Enable the matching feature flag (csv, json, parquet, ipc) for the file type you write; in Python install the full polars wheel rather than a minimal build."],"exampleFix":"cargo build --features parquet  # enable the writer feature","handlingStrategy":"fallback","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"68506541d2de983056c9eb244e1ea05fab377dfc","analyzedAt":"2026-08-19T12:15:06.350Z","contentChangedAt":"2026-08-19T12:15:06.350Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}