{"record":{"id":"19483b5597186f46","repo":"GitoxideLabs/gitoxide","slug":"parser-must-have-set-some-object-value","errorCode":null,"errorMessage":"parser must have set some object value","messagePattern":"parser must have set some object value","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"error","filePath":"gitoxide-core/src/repository/revision/explain.rs","lineNumber":52,"sourceCode":"    fn new(out: &'a mut impl std::io::Write) -> Self {\n        Explain {\n            out,\n            call: 0,\n            ref_name: None,\n            oid_prefix: None,\n            has_implicit_anchor: false,\n            err: None,\n        }\n    }\n    fn prefix(&mut self) -> Result<(), Exn> {\n        self.call += 1;\n        write!(self.out, \"{:02}. \", self.call).ok();\n        Ok(())\n    }\n    fn revision_name(&self) -> BString {\n        self.ref_name.clone().unwrap_or_else(|| {\n            self.oid_prefix\n                .expect(\"parser must have set some object value\")\n                .to_string()\n                .into()\n        })\n    }\n}\n\nimpl delegate::Revision for Explain<'_> {\n    fn find_ref(&mut self, name: &BStr) -> Result<(), Exn> {\n        self.prefix()?;\n        self.ref_name = Some(name.into());\n        writeln!(self.out, \"Lookup the '{name}' reference\").ok();\n        Ok(())\n    }\n\n    fn disambiguate_prefix(\n        &mut self,\n        prefix: gix::hash::Prefix,\n        hint: Option<delegate::PrefixHint<'_>>,","sourceCodeStart":34,"sourceCodeEnd":70,"githubUrl":"https://github.com/GitoxideLabs/gitoxide/blob/e73179060badf27222d790981fac3f84c1830a7e/gitoxide-core/src/repository/revision/explain.rs#L34-L70","documentation":"In the `gix explain` revision output, `revision_name()` expects either a parsed ref name or an object-id prefix to have been recorded by the argument parser. If neither was set, the `.expect()` panics with this message — an internal invariant violation in the CLI, not a library error.","triggerScenarios":"Invoking the explain command path where the input was resolved to neither a ref name nor an OID prefix, i.e. the parser filled neither `ref_name` nor `oid_prefix`.","commonSituations":"Passing an empty or malformed revision spec to the explain command; a regression where object resolution silently skipped setting `oid_prefix`.","solutions":["Provide a valid revision argument (ref name, OID, or prefix) to the explain command.","Fix the parser so every accepted input sets `oid_prefix` when `ref_name` is not derivable.","Replace the `.expect()` with a fallback message like `\"<unknown>\"` to avoid panics on bad input."],"exampleFix":"// before\nself.oid_prefix.expect(\"parser must have set some object value\").to_string().into()\n\n// after\nself.oid_prefix.map(|oid| oid.to_string().into()).unwrap_or_else(|| \"<no object>\".into())","handlingStrategy":"type-guard","validationCode":"// before calling explain\nif revision_arg.trim().is_empty() {\n    bail!(\"revision argument required\");\n}","typeGuard":"fn has_resolvable_name(p: &ExplainState) -> bool {\n    p.ref_name.is_some() || p.oid_prefix.is_some()\n}","tryCatchPattern":"// panic-based; guard instead\nif !has_resolvable_name(&state) {\n    bail!(\"input resolved to neither ref nor object\");\n}","preventionTips":["Always pass a non-empty revision spec to explain-style commands","Validate arguments in the parser before constructing output state","Avoid .expect() on parser-populated Option fields; use explicit errors"],"tags":["cli","panic","invariant","revision"],"backgroundTag":"internal-invariant-violation","analyzedSha":"e73179060badf27222d790981fac3f84c1830a7e","analyzedAt":"2026-09-08T11:26:50.865Z","contentChangedAt":"2026-09-08T11:26:50.865Z","schemaVersion":2},"datasetVersion":"2026-09-15T23:17:13.987Z"}