{"record":{"id":"39ed8eb5618bc44c","repo":"pbakaus/impeccable","slug":"comp-spec-cannot-read-regions-rf-e","errorCode":null,"errorMessage":"comp-spec: cannot read regions {rf}: {e}\n","messagePattern":"comp-spec: cannot read regions (.+?): (.+?)\n","errorType":"console","errorClass":null,"httpStatus":null,"severity":"error","filePath":"crates/comp-verbs/src/comp_spec.rs","lineNumber":925,"sourceCode":"            .into_iter()\n            .filter(|b| b.strength > 0.2)\n            .map(|b| format!(\"{}%\", round(b.y * 100.0) as i64))\n            .collect::<Vec<_>>()\n            .join(\" \");\n        io.out(&format!(\"BANDS {}\\n\", if bands_str.is_empty() { \"none\".to_string() } else { bands_str }));\n        io.out(\"NEXT open the grid image, then write regions.json in exactly this shape and run --regions regions.json:\\n\");\n        io.out(\"  { \\\"regions\\\": [ { \\\"id\\\": \\\"exploded-plate\\\", \\\"kind\\\": \\\"plate\\\", \\\"grid\\\": \\\"E0:H4\\\", \\\"note\\\": \\\"exploded carburetor drawing\\\" }, { \\\"id\\\": \\\"masthead\\\", \\\"kind\\\": \\\"chrome\\\", \\\"grid\\\": \\\"A0:J0\\\", \\\"note\\\": \\\"navy bar\\\" } ] }\\n\");\n        io.out(\"  kind: plate | image | texture (painted material: every illustration, photograph, figure, product object, texture; each ships as a raster plate) or text | control | chrome (code draws it). grid: <colrow>:<colrow>, A0 top-left to J9 bottom-right, inclusive.\\n\");\n        io.out(\"  A texture region is a clean sample cell of the material (ground with no ink on it), not the whole band it covers; the page tiles it. Ink that sits on the material gets its own text/control region.\\n\");\n        return 0;\n    }\n\n    let regions_input: Value = if let Some(rf) = arg(argv, \"regions\") {\n        match std::fs::read_to_string(resolve(io, rf)) {\n            Ok(raw) => match serde_json::from_str(&raw) {\n                Ok(v) => v,\n                Err(e) => {\n                    io.err(&format!(\"comp-spec: cannot read regions {rf}: {e}\\n\"));\n                    return 1;\n                }\n            },\n            Err(e) => {\n                io.err(&format!(\"comp-spec: cannot read regions {rf}: {e}\\n\"));\n                return 1;\n            }\n        }\n    } else if flag(argv, \"auto\") {\n        auto_regions(&comp)\n    } else {\n        io.err(\"comp-spec: pass --grid to get the coordinate grid, then --regions <json> (or --auto for band regions)\\n\");\n        return 1;\n    };\n    let spec = match measure_regions(&comp, &regions_input, comp_path) {\n        Ok(s) => s,\n        Err(e) => {\n            io.err(&format!(\"comp-spec: {e}\\n\"));","sourceCodeStart":907,"sourceCodeEnd":943,"githubUrl":"https://github.com/pbakaus/impeccable/blob/2bc2879276c1f321a53c4ca99d3371e411329b52/crates/comp-verbs/src/comp_spec.rs#L907-L943","documentation":"In --regions mode, comp-spec reads the regions JSON file and parses it with serde_json. This error is thrown when the file exists but its contents are not valid JSON (parse branch), so region measurement cannot proceed. The underlying serde message is appended after the path.","triggerScenarios":"`comp-spec --regions <file>` where <file> contains syntactically invalid JSON: trailing commas, single quotes, comments, BOM bytes, JSON5-style input, or a truncated write.","commonSituations":"Hand-authoring regions.json and making a syntax slip; copying the example out of the help text including the surrounding prose; editors saving with a UTF-8 BOM; an interrupted write leaving a partial file.","solutions":["Validate the file with a JSON parser (`node -e 'JSON.parse(require(\"fs\").readFileSync(\"regions.json\"))'`) and fix the reported syntax error.","Remove trailing commas, comments, and single quotes; ensure double-quoted keys.","Strip any UTF-8 BOM from the file.","Start from the exact shape shown by `comp-spec --help`: { \"regions\": [ { \"id\", \"kind\", \"grid\", \"note\" } ] }."],"exampleFix":"// before\n{ regions: [ { \"id\": \"art\", \"grid\": \"E0:J4\", } ], }   // unquoted key + trailing commas\n// after\n{ \"regions\": [ { \"id\": \"art\", \"kind\": \"plate\", \"grid\": \"E0:J4\" } ] }","handlingStrategy":"validation","validationCode":"const raw = fs.readFileSync(regionsFile, 'utf8').replace(/^\\uFEFF/, ''); // strip BOM\nconst spec = JSON.parse(raw);                       // throws with position on invalid JSON\nif (!Array.isArray(spec.regions)) throw new Error('regions file must be { \"regions\": [...] }');\nfor (const r of spec.regions) {\n  if (!r.id || !r.grid) throw new Error(`region missing id/grid: ${JSON.stringify(r)}`);\n}","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Run the regions file through JSON.parse or a linter before invoking comp-spec.","Author regions.json with double quotes, no trailing commas, no comments.","Save editor buffers without BOM (plain UTF-8).","Start from the exact template printed by `comp-spec --help`."],"tags":["cli","json","validation"],"backgroundTag":"json-parse-error","analyzedSha":"2bc2879276c1f321a53c4ca99d3371e411329b52","analyzedAt":"2026-09-08T04:51:14.109Z","contentChangedAt":"2026-09-08T04:51:14.109Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}