{"record":{"id":"ce31e1432aa29e23","repo":"Pumpkin-MC/Pumpkin","slug":"serde-error-0","errorCode":null,"errorMessage":"Serde error: {0}","messagePattern":"Serde error: (.+?)","errorType":"exception","errorClass":"Error","httpStatus":null,"severity":"error","filePath":"crates/pumpkin-nbt/src/lib.rs","lineNumber":86,"sourceCode":"pub const MAX_NBT_DEPTH: usize = 512;\n\n/// Errors produced while reading, writing, or converting NBT data.\n#[derive(Error, Debug)]\npub enum Error {\n    /// The root tag was not a compound tag and contains the reported tag ID.\n    #[error(\"The root tag of the NBT file is not a compound tag. Received tag id: {0}\")]\n    NoRootCompound(u8),\n    /// A tag ID not defined by the NBT format was encountered.\n    #[error(\"Encountered an unknown NBT tag id: {0}.\")]\n    UnknownTagId(u8),\n    /// A Java CESU-8 string could not be decoded.\n    #[error(\"Failed to Cesu 8 Decode\")]\n    Cesu8DecodingError,\n    /// A string could not be decoded as UTF-8.\n    #[error(\"Failed to UTF-8 Decode\")]\n    Utf8DecodingError,\n    /// Serde reported an invalid value or serializer state.\n    #[error(\"Serde error: {0}\")]\n    SerdeError(String),\n    /// The requested Rust type has no NBT representation.\n    #[error(\"NBT doesn't support this type: {0}\")]\n    UnsupportedType(String),\n    /// The underlying reader or writer returned an I/O error.\n    #[error(\"NBT reading was cut short: {0}\")]\n    Incomplete(io::Error),\n    /// A list or array declared a negative element count.\n    #[error(\"Negative list length: {0}\")]\n    NegativeLength(i32),\n    /// A string, list, or array exceeded the supported length.\n    #[error(\"Length too large: {0}\")]\n    LargeLength(usize),\n    /// A Bedrock variable-length integer exceeded its maximum encoded size.\n    #[error(\"Failed to decode varint - value too large\")]\n    VarIntTooLarge,\n    /// A Bedrock variable-length long exceeded its maximum encoded size.\n    #[error(\"Failed to decode varlong - value too large\")]","sourceCodeStart":68,"sourceCodeEnd":104,"githubUrl":"https://github.com/Pumpkin-MC/Pumpkin/blob/8d4639e25a57c15e47448ec327c780d41bbf2356/crates/pumpkin-nbt/src/lib.rs#L68-L104","documentation":"Error::SerdeError(String) wraps an error reported by serde while converting NBT data to/from Rust types via the serde bridge. The library throws it when serde's deserializer rejects a value (wrong shape, missing field, invalid enum variant) or a serializer hits an invalid state. The inner string carries serde's own diagnostic message.","triggerScenarios":"Deserializing an NbtCompound into a struct whose fields don't match the NBT data (missing/renamed fields, type mismatch like i32 vs i64); using serde(rename/flatten) attributes that conflict with NBT structure; serializing types serde cannot represent in the chosen NBT shape.","commonSituations":"World/version format changes where a field was renamed or its type widened; hand-written structs drifting from actual saved data; option handling — NBT has no distinct null so absent tags fail non-Option fields.","solutions":["Read the wrapped serde message: it names the failing field/value; align your struct definition with the actual NBT content.","Make optional fields Option<T> (or add #[serde(default)]) since missing NBT tags cannot populate required fields.","Verify numeric widths: NBT distinguishes byte/short/int/long; widen your Rust types or add serde conversions.","If decoding data from a different Minecraft version, regenerate the struct from a current example of the format."],"exampleFix":"// before\nstruct Spawner { delay: i32 }\n// after: field may be absent or a byte in some versions\n#[derive(Deserialize)]\nstruct Spawner {\n    #[serde(default)]\n    delay: i32,\n}","handlingStrategy":"try-catch","validationCode":"// Rust: probe the fields you depend on before full deserialization\nfn has_field(c: &NbtCompound, key: &str) -> bool { c.contains_key(key) }","typeGuard":null,"tryCatchPattern":"match MyStruct::from_nbt(compound) {\n    Err(pumpkin_nbt::Error::SerdeError(msg)) => eprintln!(\"serde: {msg} - check struct fields\"),\n    Err(e) => return Err(e.into()),\n    Ok(v) => v,\n}","preventionTips":["Model optional NBT tags as Option<T> or #[serde(default)] fields","Match numeric widths exactly (byte/short/int/long) to the NBT data","Regenerate structs when the Minecraft data format version changes"],"tags":["minecraft","nbt","serde","deserialization"],"backgroundTag":"json-unmarshal-failed","analyzedSha":"8d4639e25a57c15e47448ec327c780d41bbf2356","analyzedAt":"2026-09-09T15:32:22.916Z","contentChangedAt":"2026-09-09T15:32:22.916Z","schemaVersion":2},"datasetVersion":"2026-09-15T23:17:13.987Z"}