{"record":{"id":"b9a8a4f1b6384f6a","repo":"oraios/serena","slug":"invalid-json-in-nixd-configuration-file-config-p","errorCode":null,"errorMessage":"Invalid JSON in nixd configuration file '{config_path}': {exc.msg} (line {exc.lineno}, column {exc.colno})","messagePattern":"Invalid JSON in nixd configuration file '(.+?)': (.+?) \\(line (.+?), column (.+?)\\)","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"src/solidlsp/language_servers/nixd_ls.py","lineNumber":259,"sourceCode":"        :return: The value of the nixd configuration section.\n        :raises ValueError: If ``config_path`` or its JSON document has an invalid shape.\n        :raises RuntimeError: If the configuration file cannot be read.\n        \"\"\"\n        config_path_value = custom_settings.get(\"config_path\")\n        if config_path_value is None:\n            return cls._create_default_nixd_settings()\n        if not isinstance(config_path_value, str) or not config_path_value.strip():\n            raise ValueError(\"ls_specific_settings.nix.config_path must be a non-empty absolute path\")\n\n        config_path = Path(config_path_value).expanduser()\n        if not config_path.is_absolute():\n            raise ValueError(f\"ls_specific_settings.nix.config_path must be absolute: {config_path_value!r}\")\n\n        try:\n            with config_path.open(encoding=\"utf-8\") as config_file:\n                settings = json.load(config_file)\n        except json.JSONDecodeError as exc:\n            raise ValueError(\n                f\"Invalid JSON in nixd configuration file '{config_path}': {exc.msg} (line {exc.lineno}, column {exc.colno})\"\n            ) from exc\n        except OSError as exc:\n            raise RuntimeError(f\"Failed to read nixd configuration file '{config_path}': {exc}\") from exc\n\n        if not isinstance(settings, dict):\n            raise ValueError(\n                f\"Invalid nixd configuration file '{config_path}': expected a JSON object containing the value of the 'nixd' section\"\n            )\n        return settings\n\n    @staticmethod\n    def _resolve_nixd_configuration_section(settings: dict[str, Any], section: object) -> Any:\n        \"\"\"Resolve a ``nixd`` configuration section from the effective settings.\"\"\"\n        if section == \"nixd\":\n            return deepcopy(settings)\n        if not isinstance(section, str) or not section.startswith(\"nixd.\"):\n            return {}","sourceCodeStart":241,"sourceCodeEnd":277,"githubUrl":"https://github.com/oraios/serena/blob/7fcbca7e62555ec2287ddb2f083caee805848ea6/src/solidlsp/language_servers/nixd_ls.py#L241-L277","documentation":"When the config_path file exists but is not valid JSON, json.load raises JSONDecodeError, which _load_nixd_settings converts into a ValueError that includes the file path, the parse message, and the line/column of the syntax error.","triggerScenarios":"The file at ls_specific_settings.nix.config_path contains a JSON syntax error (trailing comma, comments, single quotes, truncation) and the nixd language server is constructed.","commonSituations":"Hand-edited nixd config with a trailing comma; writing JSONC-style comments into a .json file; a crashed editor leaving a truncated file; copying YAML into a .json file.","solutions":["Fix the JSON at the reported line/column (remove trailing commas, comments, or stray characters).","Validate the file with `python -m json.tool <config_path>` before restarting.","Regenerate the file if truncated, or point config_path at a known-good nixd settings file."],"exampleFix":"// before (nixd.json)\n{ \"nixd\": { \"formatting\": { \"command\": [\"nixfmt\"], }, } }\n// after\n{ \"nixd\": { \"formatting\": { \"command\": [\"nixfmt\"] } } }","handlingStrategy":"validation","validationCode":"import json\nfrom pathlib import Path\np = Path(config_path).expanduser()\njson.loads(p.read_text(encoding=\"utf-8\"))  # raises with line/col before server start","typeGuard":null,"tryCatchPattern":"try:\n    server = NixdLanguageServer(...)\nexcept ValueError as e:\n    if \"Invalid JSON in nixd configuration file\" in str(e):\n        restore_valid_config()  # e.g. regenerate or fix the reported line/column\n    else:\n        raise","preventionTips":["Validate JSON with `python -m json.tool` after every manual edit.","Never put JSONC comments or trailing commas in nixd config files.","Keep nixd config files under version control to catch truncation/corruption."],"tags":["json","configuration","parse-error","nixd"],"backgroundTag":"invalid-json-config","analyzedSha":"7fcbca7e62555ec2287ddb2f083caee805848ea6","analyzedAt":"2026-08-29T00:04:09.619Z","schemaVersion":2},"datasetVersion":"2026-08-29T02:17:18.158Z"}