nu_protocol/errors/shell_error/

mod.rs

use super::chained_error::ChainedError;
use crate::{
    ConfigError, FromValue, LabeledError, ParseError, Span, Spanned, Type, Value,
    ast::Operator,
    engine::{Stack, StateWorkingSet},
    format_cli_error, record,
};
use job::JobError;
use miette::{Diagnostic, LabeledSpan, NamedSource};
use serde::{Deserialize, Serialize};
use std::num::NonZeroI32;
use thiserror::Error;

pub mod bridge;
pub mod io;
pub mod job;
pub mod location;
pub mod network;

/// The fundamental error type for the evaluation engine. These cases represent different kinds of errors
/// the evaluator might face, along with helpful spans to label. An error renderer will take this error value
/// and pass it into an error viewer to display to the user.
#[derive(Debug, Clone, Error, Diagnostic, PartialEq)]
pub enum ShellError {
    /// One or more of the values have types not supported by the operator.
    #[error("The '{op}' operator does not work on values of type '{unsupported}'.")]
    #[diagnostic(code(nu::shell::operator_unsupported_type))]
    OperatorUnsupportedType {
        op: Operator,
        unsupported: Type,
        #[label = "does not support '{unsupported}'"]
        op_span: Span,
        #[label("{unsupported}")]
        unsupported_span: Span,
        #[help]
        help: Option<&'static str>,
    },

    /// The operator supports the types of both values, but not the specific combination of their types.
    #[error("Types '{lhs}' and '{rhs}' are not compatible for the '{op}' operator.")]
    #[diagnostic(code(nu::shell::operator_incompatible_types))]
    OperatorIncompatibleTypes {
        op: Operator,
        lhs: Type,
        rhs: Type,
        #[label = "does not operate between '{lhs}' and '{rhs}'"]
        op_span: Span,
        #[label("{lhs}")]
        lhs_span: Span,
        #[label("{rhs}")]
        rhs_span: Span,
        #[help]
        help: Option<&'static str>,
    },

    /// An arithmetic operation's resulting value overflowed its possible size.
    ///
    /// ## Resolution
    ///
    /// Check the inputs to the operation and add guards for their sizes.
    /// Integers are generally of size i64, floats are generally f64.
    #[error("Operator overflow.")]
    #[diagnostic(code(nu::shell::operator_overflow))]
    OperatorOverflow {
        msg: String,
        #[label = "{msg}"]
        span: Span,
        #[help]
        help: Option<String>,
    },

    /// The pipelined input into a command was not of the expected type. For example, it might
    /// expect a string input, but received a table instead.
    ///
    /// ## Resolution
    ///
    /// Check the relevant pipeline and extract or convert values as needed.
    #[error("Pipeline mismatch.")]
    #[diagnostic(code(nu::shell::pipeline_mismatch))]
    PipelineMismatch {
        exp_input_type: String,
        #[label("expected: {exp_input_type}")]
        dst_span: Span,
        #[label("value originates here")]
        src_span: Span,
    },

    // TODO: properly unify
    /// The pipelined input into a command was not of the expected type. For example, it might
    /// expect a string input, but received a table instead.
    ///
    /// (duplicate of [`ShellError::PipelineMismatch`] that reports the observed type)
    ///
    /// ## Resolution
    ///
    /// Check the relevant pipeline and extract or convert values as needed.
    #[error("Input type not supported.")]
    #[diagnostic(code(nu::shell::only_supports_this_input_type))]
    OnlySupportsThisInputType {
        exp_input_type: String,
        wrong_type: String,
        #[label("only {exp_input_type} input data is supported")]
        dst_span: Span,
        #[label("input type: {wrong_type}")]
        src_span: Span,
    },

    /// No input value was piped into the command.
    ///
    /// ## Resolution
    ///
    /// Only use this command to process values from a previous expression.
    #[error("Pipeline empty.")]
    #[diagnostic(code(nu::shell::pipeline_mismatch))]
    PipelineEmpty {
        #[label("no input value was piped in")]
        dst_span: Span,
    },

    // TODO: remove non type error usages
    /// A command received an argument of the wrong type.
    ///
    /// ## Resolution
    ///
    /// Convert the argument type before passing it in, or change the command to accept the type.
    #[error("Type mismatch.")]
    #[diagnostic(code(nu::shell::type_mismatch))]
    TypeMismatch {
        err_message: String,
        #[label = "{err_message}"]
        span: Span,
    },

    /// A value's type did not match the expected type.
    ///
    /// ## Resolution
    ///
    /// Convert the value to the correct type or provide a value of the correct type.
    #[error("Type mismatch")]
    #[diagnostic(code(nu::shell::type_mismatch))]
    RuntimeTypeMismatch {
        expected: Type,
        actual: Type,
        #[label = "expected {expected}, but got {actual}"]
        span: Span,
    },

    /// A value had the correct type but is otherwise invalid.
    ///
    /// ## Resolution
    ///
    /// Ensure the value meets the criteria in the error message.
    #[error("Invalid value")]
    #[diagnostic(code(nu::shell::invalid_value))]
    InvalidValue {
        valid: String,
        actual: String,
        #[label = "expected {valid}, but got {actual}"]
        span: Span,
    },

    /// A command received an argument with correct type but incorrect value.
    ///
    /// ## Resolution
    ///
    /// Correct the argument value before passing it in or change the command.
    #[error("Incorrect value.")]
    #[diagnostic(code(nu::shell::incorrect_value))]
    IncorrectValue {
        msg: String,
        #[label = "{msg}"]
        val_span: Span,
        #[label = "encountered here"]
        call_span: Span,
    },

    /// Invalid assignment left-hand side
    ///
    /// ## Resolution
    ///
    /// Assignment requires that you assign to a variable or variable cell path.
    #[error("Assignment operations require a variable.")]
    #[diagnostic(code(nu::shell::assignment_requires_variable))]
    AssignmentRequiresVar {
        #[label = "needs to be a variable"]
        lhs_span: Span,
    },

    /// Invalid assignment left-hand side
    ///
    /// ## Resolution
    ///
    /// Assignment requires that you assign to a mutable variable or cell path.
    #[error("Assignment to an immutable variable.")]
    #[diagnostic(code(nu::shell::assignment_requires_mutable_variable))]
    AssignmentRequiresMutableVar {
        #[label = "needs to be a mutable variable"]
        lhs_span: Span,
    },

    /// An operator was not recognized during evaluation.
    ///
    /// ## Resolution
    ///
    /// Did you write the correct operator?
    #[error("Unknown operator: {op_token}.")]
    #[diagnostic(code(nu::shell::unknown_operator))]
    UnknownOperator {
        op_token: String,
        #[label = "unknown operator"]
        span: Span,
    },

    /// An expected command parameter is missing.
    ///
    /// ## Resolution
    ///
    /// Add the expected parameter and try again.
    #[error("Missing parameter: {param_name}.")]
    #[diagnostic(code(nu::shell::missing_parameter))]
    MissingParameter {
        param_name: String,
        #[label = "missing parameter: {param_name}"]
        span: Span,
    },

    /// Two parameters conflict with each other or are otherwise mutually exclusive.
    ///
    /// ## Resolution
    ///
    /// Remove one of the parameters/options and try again.
    #[error("Incompatible parameters.")]
    #[diagnostic(code(nu::shell::incompatible_parameters))]
    IncompatibleParameters {
        left_message: String,
        // Be cautious, as flags can share the same span, resulting in a panic (ex: `rm -pt`)
        #[label("{left_message}")]
        left_span: Span,
        right_message: String,
        #[label("{right_message}")]
        right_span: Span,
    },

    /// There's some issue with number or matching of delimiters in an expression.
    ///
    /// ## Resolution
    ///
    /// Check your syntax for mismatched braces, RegExp syntax errors, etc, based on the specific error message.
    #[error("Delimiter error")]
    #[diagnostic(code(nu::shell::delimiter_error))]
    DelimiterError {
        msg: String,
        #[label("{msg}")]
        span: Span,
    },

    /// An operation received parameters with some sort of incompatibility
    /// (for example, different number of rows in a table, incompatible column names, etc).
    ///
    /// ## Resolution
    ///
    /// Refer to the specific error message for details on what's incompatible and then fix your
    /// inputs to make sure they match that way.
    #[error("Incompatible parameters.")]
    #[diagnostic(code(nu::shell::incompatible_parameters))]
    IncompatibleParametersSingle {
        msg: String,
        #[label = "{msg}"]
        span: Span,
    },

    /// You're trying to run an unsupported external command.
    ///
    /// ## Resolution
    ///
    /// Make sure there's an appropriate `run-external` declaration for this external command.
    #[error("Running external commands not supported")]
    #[diagnostic(code(nu::shell::external_commands))]
    ExternalNotSupported {
        #[label = "external not supported"]
        span: Span,
    },

    // TODO: consider moving to a more generic error variant for invalid values
    /// The given probability input is invalid. The probability must be between 0 and 1.
    ///
    /// ## Resolution
    ///
    /// Make sure the probability is between 0 and 1 and try again.
    #[error("Invalid Probability.")]
    #[diagnostic(code(nu::shell::invalid_probability))]
    InvalidProbability {
        #[label = "invalid probability: must be between 0 and 1"]
        span: Span,
    },

    /// The first value in a `..` range must be compatible with the second one.
    ///
    /// ## Resolution
    ///
    /// Check to make sure both values are compatible, and that the values are enumerable in Nushell.
    #[error("Invalid range {left_flank}..{right_flank}")]
    #[diagnostic(code(nu::shell::invalid_range))]
    InvalidRange {
        left_flank: String,
        right_flank: String,
        #[label = "expected a valid range"]
        span: Span,
    },

    /// Catastrophic nushell failure. This reflects a completely unexpected or unrecoverable error.
    ///
    /// ## Resolution
    ///
    /// It is very likely that this is a bug. Please file an issue at <https://github.com/nushell/nushell/issues> with relevant information.
    #[error("Nushell failed: {msg}.")]
    #[diagnostic(
        code(nu::shell::nushell_failed),
        help(
            "This shouldn't happen. Please file an issue: https://github.com/nushell/nushell/issues"
        )
    )]
    // Only use this one if Nushell completely falls over and hits a state that isn't possible or isn't recoverable
    NushellFailed { msg: String },

    /// Catastrophic nushell failure. This reflects a completely unexpected or unrecoverable error.
    ///
    /// ## Resolution
    ///
    /// It is very likely that this is a bug. Please file an issue at <https://github.com/nushell/nushell/issues> with relevant information.
    #[error("Nushell failed: {msg}.")]
    #[diagnostic(
        code(nu::shell::nushell_failed_spanned),
        help(
            "This shouldn't happen. Please file an issue: https://github.com/nushell/nushell/issues"
        )
    )]
    // Only use this one if Nushell completely falls over and hits a state that isn't possible or isn't recoverable
    NushellFailedSpanned {
        msg: String,
        label: String,
        #[label = "{label}"]
        span: Span,
    },

    /// Catastrophic nushell failure. This reflects a completely unexpected or unrecoverable error.
    ///
    /// ## Resolution
    ///
    /// It is very likely that this is a bug. Please file an issue at <https://github.com/nushell/nushell/issues> with relevant information.
    #[error("Nushell failed: {msg}.")]
    #[diagnostic(code(nu::shell::nushell_failed_help))]
    // Only use this one if Nushell completely falls over and hits a state that isn't possible or isn't recoverable
    NushellFailedHelp {
        msg: String,
        #[help]
        help: String,
    },

    /// A referenced variable was not found at runtime.
    ///
    /// ## Resolution
    ///
    /// Check the variable name. Did you typo it? Did you forget to declare it? Is the casing right?
    #[error("Variable not found")]
    #[diagnostic(code(nu::shell::variable_not_found))]
    VariableNotFoundAtRuntime {
        #[label = "variable not found"]
        span: Span,
    },

    /// A referenced environment variable was not found at runtime.
    ///
    /// ## Resolution
    ///
    /// Check the environment variable name. Did you typo it? Did you forget to declare it? Is the casing right?
    #[error("Environment variable '{envvar_name}' not found")]
    #[diagnostic(code(nu::shell::env_variable_not_found))]
    EnvVarNotFoundAtRuntime {
        envvar_name: String,
        #[label = "environment variable not found"]
        span: Span,
    },

    /// A referenced module was not found at runtime.
    ///
    /// ## Resolution
    ///
    /// Check the module name. Did you typo it? Did you forget to declare it? Is the casing right?
    #[error("Module '{mod_name}' not found")]
    #[diagnostic(code(nu::shell::module_not_found))]
    ModuleNotFoundAtRuntime {
        mod_name: String,
        #[label = "module not found"]
        span: Span,
    },

    /// A referenced overlay was not found at runtime.
    ///
    /// ## Resolution
    ///
    /// Check the overlay name. Did you typo it? Did you forget to declare it? Is the casing right?
    #[error("Overlay '{overlay_name}' not found")]
    #[diagnostic(code(nu::shell::overlay_not_found))]
    OverlayNotFoundAtRuntime {
        overlay_name: String,
        #[label = "overlay not found"]
        span: Span,
    },

    /// The given item was not found. This is a fairly generic error that depends on context.
    ///
    /// ## Resolution
    ///
    /// This error is triggered in various places, and simply signals that "something" was not found. Refer to the specific error message for further details.
    #[error("Not found.")]
    #[diagnostic(code(nu::parser::not_found))]
    NotFound {
        #[label = "did not find anything under this name"]
        span: Span,
    },

    /// Failed to convert a value of one type into a different type.
    ///
    /// ## Resolution
    ///
    /// Not all values can be coerced this way. Check the supported type(s) and try again.
    #[error("Can't convert to {to_type}.")]
    #[diagnostic(code(nu::shell::cant_convert))]
    CantConvert {
        to_type: String,
        from_type: String,
        #[label("can't convert {from_type} to {to_type}")]
        span: Span,
        #[help]
        help: Option<String>,
    },

    /// Failed to convert a value of one type into a different type by specifying a unit.
    ///
    /// ## Resolution
    ///
    /// Check that the provided value can be converted in the provided: only Durations can be converted to duration units, and only Filesize can be converted to filesize units.
    #[error("Can't convert {from_type} to the specified unit.")]
    #[diagnostic(code(nu::shell::cant_convert_value_to_unit))]
    CantConvertToUnit {
        to_type: String,
        from_type: String,
        #[label("can't convert {from_type} to {to_type}")]
        span: Span,
        #[label("conversion originates here")]
        unit_span: Span,
        #[help]
        help: Option<String>,
    },

    /// An environment variable cannot be represented as a string.
    ///
    /// ## Resolution
    ///
    /// Not all types can be converted to environment variable values, which must be strings. Check the input type and try again.
    #[error("'{envvar_name}' is not representable as a string.")]
    #[diagnostic(
            code(nu::shell::env_var_not_a_string),
            help(
                r#"The '{envvar_name}' environment variable must be a string or be convertible to a string.
    Either make sure '{envvar_name}' is a string, or add a 'to_string' entry for it in ENV_CONVERSIONS."#
            )
        )]
    EnvVarNotAString {
        envvar_name: String,
        #[label("value not representable as a string")]
        span: Span,
    },

    /// This environment variable cannot be set manually.
    ///
    /// ## Resolution
    ///
    /// This environment variable is set automatically by Nushell and cannot not be set manually.
    #[error("{envvar_name} cannot be set manually.")]
    #[diagnostic(
        code(nu::shell::automatic_env_var_set_manually),
        help(
            r#"The environment variable '{envvar_name}' is set automatically by Nushell and cannot be set manually."#
        )
    )]
    AutomaticEnvVarSetManually {
        envvar_name: String,
        #[label("cannot set '{envvar_name}' manually")]
        span: Span,
    },

    /// It is not possible to replace the entire environment at once
    ///
    /// ## Resolution
    ///
    /// Setting the entire environment is not allowed. Change environment variables individually
    /// instead.
    #[error("Cannot replace environment.")]
    #[diagnostic(
        code(nu::shell::cannot_replace_env),
        help(r#"Assigning a value to '$env' is not allowed."#)
    )]
    CannotReplaceEnv {
        #[label("setting '$env' not allowed")]
        span: Span,
    },

    /// Division by zero is not a thing.
    ///
    /// ## Resolution
    ///
    /// Add a guard of some sort to check whether a denominator input to this division is zero, and branch off if that's the case.
    #[error("Division by zero.")]
    #[diagnostic(code(nu::shell::division_by_zero))]
    DivisionByZero {
        #[label("division by zero")]
        span: Span,
    },

    /// An error happened while trying to create a range.
    ///
    /// This can happen in various unexpected situations, for example if the range would loop forever (as would be the case with a 0-increment).
    ///
    /// ## Resolution
    ///
    /// Check your range values to make sure they're countable and would not loop forever.
    #[error("Can't convert range to countable values")]
    #[diagnostic(code(nu::shell::range_to_countable))]
    CannotCreateRange {
        #[label = "can't convert to countable values"]
        span: Span,
    },

    /// You attempted to access an index beyond the available length of a value.
    ///
    /// ## Resolution
    ///
    /// Check your lengths and try again.
    #[error("Row number too large (max: {max_idx}).")]
    #[diagnostic(code(nu::shell::access_beyond_end))]
    AccessBeyondEnd {
        max_idx: usize,
        #[label = "index too large (max: {max_idx})"]
        span: Span,
    },

    /// You attempted to insert data at a list position higher than the end.
    ///
    /// ## Resolution
    ///
    /// To insert data into a list, assign to the last used index + 1.
    #[error("Inserted at wrong row number (should be {available_idx}).")]
    #[diagnostic(code(nu::shell::access_beyond_end))]
    InsertAfterNextFreeIndex {
        available_idx: usize,
        #[label = "can't insert at index (the next available index is {available_idx})"]
        span: Span,
    },

    /// You attempted to access an index when it's empty.
    ///
    /// ## Resolution
    ///
    /// Check your lengths and try again.
    #[error("Row number too large (empty content).")]
    #[diagnostic(code(nu::shell::access_beyond_end))]
    AccessEmptyContent {
        #[label = "index too large (empty content)"]
        span: Span,
    },

    // TODO: check to be taken over by `AccessBeyondEnd`
    /// You attempted to access an index beyond the available length of a stream.
    ///
    /// ## Resolution
    ///
    /// Check your lengths and try again.
    #[error("Row number too large.")]
    #[diagnostic(code(nu::shell::access_beyond_end_of_stream))]
    AccessBeyondEndOfStream {
        #[label = "index too large"]
        span: Span,
    },

    /// Tried to index into a type that does not support pathed access.
    ///
    /// ## Resolution
    ///
    /// Check your types. Only composite types can be pathed into.
    #[error("Data cannot be accessed with a cell path")]
    #[diagnostic(code(nu::shell::incompatible_path_access))]
    IncompatiblePathAccess {
        type_name: String,
        #[label("{type_name} doesn't support cell paths")]
        span: Span,
    },

    /// The requested column does not exist.
    ///
    /// ## Resolution
    ///
    /// Check the spelling of your column name. Did you forget to rename a column somewhere?
    #[error("Cannot find column '{col_name}'")]
    #[diagnostic(code(nu::shell::column_not_found))]
    CantFindColumn {
        col_name: String,
        #[label = "cannot find column '{col_name}'"]
        span: Option<Span>,
        #[label = "value originates here"]
        src_span: Span,
    },

    /// Attempted to insert a column into a table, but a column with that name already exists.
    ///
    /// ## Resolution
    ///
    /// Drop or rename the existing column (check `rename -h`) and try again.
    #[error("Column already exists")]
    #[diagnostic(code(nu::shell::column_already_exists))]
    ColumnAlreadyExists {
        col_name: String,
        #[label = "column '{col_name}' already exists"]
        span: Span,
        #[label = "value originates here"]
        src_span: Span,
    },

    /// The given operation can only be performed on lists.
    ///
    /// ## Resolution
    ///
    /// Check the input type to this command. Are you sure it's a list?
    #[error("Not a list value")]
    #[diagnostic(code(nu::shell::not_a_list))]
    NotAList {
        #[label = "value not a list"]
        dst_span: Span,
        #[label = "value originates here"]
        src_span: Span,
    },

    /// Fields can only be defined once
    ///
    /// ## Resolution
    ///
    /// Check the record to ensure you aren't reusing the same field name
    #[error("Record field or table column used twice: {col_name}")]
    #[diagnostic(code(nu::shell::column_defined_twice))]
    ColumnDefinedTwice {
        col_name: String,
        #[label = "field redefined here"]
        second_use: Span,
        #[label = "field first defined here"]
        first_use: Span,
    },

    /// Attempted to create a record from different number of columns and values
    ///
    /// ## Resolution
    ///
    /// Check the record has the same number of columns as values
    #[error("Attempted to create a record from different number of columns and values")]
    #[diagnostic(code(nu::shell::record_cols_vals_mismatch))]
    RecordColsValsMismatch {
        #[label = "problematic value"]
        bad_value: Span,
        #[label = "attempted to create the record here"]
        creation_site: Span,
    },

    /// Failed to detect columns
    ///
    /// ## Resolution
    ///
    /// Use `detect columns --guess` or `parse` instead
    #[error("Failed to detect columns")]
    #[diagnostic(code(nu::shell::failed_to_detect_columns))]
    ColumnDetectionFailure {
        #[label = "value coming from here"]
        bad_value: Span,
        #[label = "tried to detect columns here"]
        failure_site: Span,
    },

    /// Attempted to us a relative range on an infinite stream
    ///
    /// ## Resolution
    ///
    /// Ensure that either the range is absolute or the stream has a known length.
    #[error("Relative range values cannot be used with streams that don't have a known length")]
    #[diagnostic(code(nu::shell::relative_range_on_infinite_stream))]
    RelativeRangeOnInfiniteStream {
        #[label = "Relative range values cannot be used with streams that don't have a known length"]
        span: Span,
    },

    /// An error happened while performing an external command.
    ///
    /// ## Resolution
    ///
    /// This error is fairly generic. Refer to the specific error message for further details.
    #[error("External command failed")]
    #[diagnostic(code(nu::shell::external_command), help("{help}"))]
    ExternalCommand {
        label: String,
        help: String,
        #[label("{label}")]
        span: Span,
    },

    /// An external command exited with a non-zero exit code.
    ///
    /// ## Resolution
    ///
    /// Check the external command's error message.
    #[error("External command had a non-zero exit code")]
    #[diagnostic(code(nu::shell::non_zero_exit_code))]
    NonZeroExitCode {
        exit_code: NonZeroI32,
        #[label("exited with code {exit_code}")]
        span: Span,
    },

    #[cfg(unix)]
    /// An external command exited due to a signal.
    ///
    /// ## Resolution
    ///
    /// Check why the signal was sent or triggered.
    #[error("External command was terminated by a signal")]
    #[diagnostic(code(nu::shell::terminated_by_signal))]
    TerminatedBySignal {
        signal_name: String,
        signal: i32,
        #[label("terminated by {signal_name} ({signal})")]
        span: Span,
    },

    #[cfg(unix)]
    /// An external command core dumped.
    ///
    /// ## Resolution
    ///
    /// Check why the core dumped was triggered.
    #[error("External command core dumped")]
    #[diagnostic(code(nu::shell::core_dumped))]
    CoreDumped {
        signal_name: String,
        signal: i32,
        #[label("core dumped with {signal_name} ({signal})")]
        span: Span,
    },

    /// An operation was attempted with an input unsupported for some reason.
    ///
    /// ## Resolution
    ///
    /// This error is fairly generic. Refer to the specific error message for further details.
    #[error("Unsupported input")]
    #[diagnostic(code(nu::shell::unsupported_input))]
    UnsupportedInput {
        msg: String,
        input: String,
        #[label("{msg}")]
        msg_span: Span,
        #[label("{input}")]
        input_span: Span,
    },

    /// Failed to parse an input into a datetime value.
    ///
    /// ## Resolution
    ///
    /// Make sure your datetime input format is correct.
    ///
    /// For example, these are some valid formats:
    ///
    /// * "5 pm"
    /// * "2020/12/4"
    /// * "2020.12.04 22:10 +2"
    /// * "2020-04-12 22:10:57 +02:00"
    /// * "2020-04-12T22:10:57.213231+02:00"
    /// * "Tue, 1 Jul 2003 10:52:37 +0200""#
    #[error("Unable to parse datetime: [{msg}].")]
    #[diagnostic(
        code(nu::shell::datetime_parse_error),
        help(
            r#"Examples of supported inputs:
 * "5 pm"
 * "2020/12/4"
 * "2020.12.04 22:10 +2"
 * "2020-04-12 22:10:57 +02:00"
 * "2020-04-12T22:10:57.213231+02:00"
 * "Tue, 1 Jul 2003 10:52:37 +0200""#
        )
    )]
    DatetimeParseError {
        msg: String,
        #[label("datetime parsing failed")]
        span: Span,
    },

    /// A network operation failed.
    ///
    /// ## Resolution
    ///
    /// It's always DNS.
    #[error("Network failure")]
    #[diagnostic(code(nu::shell::network_failure))]
    NetworkFailure {
        msg: String,
        #[label("{msg}")]
        span: Span,
    },

    #[error(transparent)]
    #[diagnostic(transparent)]
    Network(#[from] network::NetworkError),

    /// Help text for this command could not be found.
    ///
    /// ## Resolution
    ///
    /// Check the spelling for the requested command and try again. Are you sure it's defined and your configurations are loading correctly? Can you execute it?
    #[error("Command not found")]
    #[diagnostic(code(nu::shell::command_not_found))]
    CommandNotFound {
        #[label("command not found")]
        span: Span,
    },

    /// This alias could not be found
    ///
    /// ## Resolution
    ///
    /// The alias does not exist in the current scope. It might exist in another scope or overlay or be hidden.
    #[error("Alias not found")]
    #[diagnostic(code(nu::shell::alias_not_found))]
    AliasNotFound {
        #[label("alias not found")]
        span: Span,
    },

    /// The registered plugin data for a plugin is invalid.
    ///
    /// ## Resolution
    ///
    /// `plugin add` the plugin again to update the data, or remove it with `plugin rm`.
    #[error("The registered plugin data for `{plugin_name}` is invalid")]
    #[diagnostic(code(nu::shell::plugin_registry_data_invalid))]
    PluginRegistryDataInvalid {
        plugin_name: String,
        #[label("plugin `{plugin_name}` loaded here")]
        span: Option<Span>,
        #[help(
            "the format in the plugin registry file is not compatible with this version of Nushell.\n\nTry adding the plugin again with `{}`"
        )]
        add_command: String,
    },

    /// A plugin failed to load.
    ///
    /// ## Resolution
    ///
    /// This is a fairly generic error. Refer to the specific error message for further details.
    #[error("Plugin failed to load: {msg}")]
    #[diagnostic(code(nu::shell::plugin_failed_to_load))]
    PluginFailedToLoad { msg: String },

    /// A message from a plugin failed to encode.
    ///
    /// ## Resolution
    ///
    /// This is likely a bug with the plugin itself.
    #[error("Plugin failed to encode: {msg}")]
    #[diagnostic(code(nu::shell::plugin_failed_to_encode))]
    PluginFailedToEncode { msg: String },

    /// A message to a plugin failed to decode.
    ///
    /// ## Resolution
    ///
    /// This is either an issue with the inputs to a plugin (bad JSON?) or a bug in the plugin itself. Fix or report as appropriate.
    #[error("Plugin failed to decode: {msg}")]
    #[diagnostic(code(nu::shell::plugin_failed_to_decode))]
    PluginFailedToDecode { msg: String },

    /// A custom value cannot be sent to the given plugin.
    ///
    /// ## Resolution
    ///
    /// Custom values can only be used with the plugin they came from. Use a command from that
    /// plugin instead.
    #[error("Custom value `{name}` cannot be sent to plugin")]
    #[diagnostic(code(nu::shell::custom_value_incorrect_for_plugin))]
    CustomValueIncorrectForPlugin {
        name: String,
        #[label("the `{dest_plugin}` plugin does not support this kind of value")]
        span: Span,
        dest_plugin: String,
        #[help("this value came from the `{}` plugin")]
        src_plugin: Option<String>,
    },

    /// The plugin failed to encode a custom value.
    ///
    /// ## Resolution
    ///
    /// This is likely a bug with the plugin itself. The plugin may have tried to send a custom
    /// value that is not serializable.
    #[error("Custom value failed to encode")]
    #[diagnostic(code(nu::shell::custom_value_failed_to_encode))]
    CustomValueFailedToEncode {
        msg: String,
        #[label("{msg}")]
        span: Span,
    },

    /// The plugin failed to encode a custom value.
    ///
    /// ## Resolution
    ///
    /// This may be a bug within the plugin, or the plugin may have been updated in between the
    /// creation of the custom value and its use.
    #[error("Custom value failed to decode")]
    #[diagnostic(code(nu::shell::custom_value_failed_to_decode))]
    #[diagnostic(help("the plugin may have been updated and no longer support this custom value"))]
    CustomValueFailedToDecode {
        msg: String,
        #[label("{msg}")]
        span: Span,
    },

    /// An I/O operation failed.
    ///
    /// ## Resolution
    ///
    /// This is the main I/O error, for further details check the error kind and additional context.
    #[error(transparent)]
    #[diagnostic(transparent)]
    Io(#[from] io::IoError),

    /// A name was not found. Did you mean a different name?
    ///
    /// ## Resolution
    ///
    /// The error message will suggest a possible match for what you meant.
    #[error("Name not found")]
    #[diagnostic(code(nu::shell::name_not_found))]
    DidYouMean {
        suggestion: String,
        #[label("did you mean '{suggestion}'?")]
        span: Span,
    },

    /// A name was not found. Did you mean a different name?
    ///
    /// ## Resolution
    ///
    /// The error message will suggest a possible match for what you meant.
    #[error("{msg}")]
    #[diagnostic(code(nu::shell::did_you_mean_custom))]
    DidYouMeanCustom {
        msg: String,
        suggestion: String,
        #[label("did you mean '{suggestion}'?")]
        span: Span,
    },

    /// The given input must be valid UTF-8 for further processing.
    ///
    /// ## Resolution
    ///
    /// Check your input's encoding. Are there any funny characters/bytes?
    #[error("Non-UTF8 string")]
    #[diagnostic(
        code(nu::parser::non_utf8),
        help("see `decode` for handling character sets other than UTF-8")
    )]
    NonUtf8 {
        #[label("non-UTF8 string")]
        span: Span,
    },

    /// The given input must be valid UTF-8 for further processing.
    ///
    /// ## Resolution
    ///
    /// Check your input's encoding. Are there any funny characters/bytes?
    #[error("Non-UTF8 string")]
    #[diagnostic(
        code(nu::parser::non_utf8_custom),
        help("see `decode` for handling character sets other than UTF-8")
    )]
    NonUtf8Custom {
        msg: String,
        #[label("{msg}")]
        span: Span,
    },

    /// Failed to update the config due to one or more errors.
    ///
    /// ## Resolution
    ///
    /// Refer to the error messages for specific details.
    #[error("Encountered {} error(s) when updating config", errors.len())]
    #[diagnostic(code(nu::shell::invalid_config))]
    InvalidConfig {
        #[related]
        errors: Vec<ConfigError>,
    },

    /// A value was missing a required column.
    ///
    /// ## Resolution
    ///
    /// Make sure the value has the required column.
    #[error("Value is missing a required '{column}' column")]
    #[diagnostic(code(nu::shell::missing_required_column))]
    MissingRequiredColumn {
        column: &'static str,
        #[label("has no '{column}' column")]
        span: Span,
    },

    /// Negative value passed when positive one is required.
    ///
    /// ## Resolution
    ///
    /// Guard against negative values or check your inputs.
    #[error("Negative value passed when positive one is required")]
    #[diagnostic(code(nu::shell::needs_positive_value))]
    NeedsPositiveValue {
        #[label("use a positive value")]
        span: Span,
    },

    /// This is a generic error type used for different situations.
    #[error("{error}")]
    #[diagnostic(code(nu::shell::error))]
    GenericError {
        error: String,
        msg: String,
        #[label("{msg}")]
        span: Option<Span>,
        #[help]
        help: Option<String>,
        #[related]
        inner: Vec<ShellError>,
    },

    /// This is a generic error type used for different situations.
    #[error("{error}")]
    #[diagnostic(code(nu::shell::outsidespan))]
    OutsideSpannedLabeledError {
        #[source_code]
        src: String,
        error: String,
        msg: String,
        #[label("{msg}")]
        span: Span,
    },

    /// This is a generic error type used for different situations that need
    /// multiple labels.
    #[error("{msg}")]
    #[diagnostic(code(nu::shell::outside), url("{url}"))]
    OutsideSource {
        #[source_code]
        src: NamedSource<String>,
        msg: String,
        url: String,
        #[help]
        help: Option<String>,
        // Defaults to an empty string so it just underlines
        #[label(collection, "")]
        labels: Vec<LabeledSpan>,
        #[related]
        inner: Vec<ShellError>,
    },

    /// This is a generic error type used for different situations that need
    /// multiple labels, minus the URL
    #[error("{msg}")]
    #[diagnostic(code(nu::shell::outside))]
    OutsideSourceNoUrl {
        #[source_code]
        src: NamedSource<String>,
        msg: String,
        #[help]
        help: Option<String>,
        // Defaults to an empty string so it just underlines
        #[label(collection, "")]
        labels: Vec<LabeledSpan>,
        #[related]
        inner: Vec<ShellError>,
    },

    /// This is a generic error type used for user and plugin-generated errors.
    #[error(transparent)]
    #[diagnostic(transparent)]
    LabeledError(#[from] Box<super::LabeledError>),

    /// Attempted to use a command that has been removed from Nushell.
    ///
    /// ## Resolution
    ///
    /// Check the help for the new suggested command and update your script accordingly.
    #[error("Removed command: {removed}")]
    #[diagnostic(code(nu::shell::removed_command))]
    RemovedCommand {
        removed: String,
        replacement: String,
        #[label("'{removed}' has been removed from Nushell. Please use '{replacement}' instead.")]
        span: Span,
    },

    // It should be only used by commands accepts block, and accept inputs from pipeline.
    /// Failed to eval block with specific pipeline input.
    #[error("Eval block failed with pipeline input")]
    #[diagnostic(code(nu::shell::eval_block_with_input))]
    EvalBlockWithInput {
        #[label("source value")]
        span: Span,
        #[related]
        sources: Vec<ShellError>,
    },

    /// Break event, which may become an error if used outside of a loop
    #[error("Break used outside of loop")]
    Break {
        #[label("used outside of loop")]
        span: Span,
    },

    /// Continue event, which may become an error if used outside of a loop
    #[error("Continue used outside of loop")]
    Continue {
        #[label("used outside of loop")]
        span: Span,
    },

    /// Return event, which may become an error if used outside of a custom command or closure
    #[error("Return used outside of custom command or closure")]
    Return {
        #[label("used outside of custom command or closure")]
        span: Span,
        value: Box<Value>,
    },

    /// Exit event, it can still be caught by `try {..} finally {..}` block.
    #[error("Exit doesn't catch internally")]
    #[diagnostic(
        code(nu::shell::exit),
        help(
            "This shouldn't happen. Please file an issue: https://github.com/nushell/nushell/issues"
        )
    )]
    Exit { code: i32 },

    /// The code being executed called itself too many times.
    ///
    /// ## Resolution
    ///
    /// Adjust your Nu code to
    #[error("Recursion limit ({recursion_limit}) reached")]
    #[diagnostic(code(nu::shell::recursion_limit_reached))]
    RecursionLimitReached {
        recursion_limit: u64,
        #[label("This called itself too many times")]
        span: Option<Span>,
    },

    /// Operation interrupted
    #[error("Operation interrupted")]
    Interrupted {
        #[label("This operation was interrupted")]
        span: Span,
    },

    /// An attempt to use, as a match guard, an expression that
    /// does not resolve into a boolean
    #[error("Match guard not bool")]
    #[diagnostic(
        code(nu::shell::match_guard_not_bool),
        help("Match guards should evaluate to a boolean")
    )]
    MatchGuardNotBool {
        #[label("not a boolean expression")]
        span: Span,
    },

    /// An attempt to run a command marked for constant evaluation lacking the const. eval.
    /// implementation.
    ///
    /// This is an internal Nushell error, please file an issue.
    #[error("Missing const eval implementation")]
    #[diagnostic(
        code(nu::shell::missing_const_eval_implementation),
        help(
            "The command lacks an implementation for constant evaluation. \
This is an internal Nushell error, please file an issue https://github.com/nushell/nushell/issues."
        )
    )]
    MissingConstEvalImpl {
        #[label("command lacks constant implementation")]
        span: Span,
    },

    /// TODO: Get rid of this error by moving the check before evaluation
    ///
    /// Tried evaluating of a subexpression with parsing error
    ///
    /// ## Resolution
    ///
    /// Fix the parsing error first.
    #[error("Found parsing error in expression.")]
    #[diagnostic(
        code(nu::shell::parse_error_in_constant),
        help(
            "This expression is supposed to be evaluated into a constant, which means error-free."
        )
    )]
    ParseErrorInConstant {
        #[label("Parsing error detected in expression")]
        span: Span,
    },

    /// Tried assigning non-constant value to a constant
    ///
    /// ## Resolution
    ///
    /// Only a subset of expressions are allowed to be assigned as a constant during parsing.
    #[error("Not a constant.")]
    #[diagnostic(
        code(nu::shell::not_a_constant),
        help(
            "Only a subset of expressions are allowed constants during parsing. Try using the 'const' command or typing the value literally."
        )
    )]
    NotAConstant {
        #[label("Value is not a parse-time constant")]
        span: Span,
    },

    // TODO: Update help text once custom const commands are supported
    /// Tried running a command that is not const-compatible
    ///
    /// ## Resolution
    ///
    /// Only a subset of builtin commands can run at parse time.
    #[error("Not a const command.")]
    #[diagnostic(
        code(nu::shell::not_a_const_command),
        help("Only a subset of builtin commands can run at parse time.")
    )]
    NotAConstCommand {
        #[label("This command cannot run at parse time.")]
        span: Span,
    },

    /// Tried getting a help message at parse time.
    ///
    /// ## Resolution
    ///
    /// Help messages are not supported at parse time.
    #[error("Help message not a constant.")]
    #[diagnostic(
        code(nu::shell::not_a_const_help),
        help("Help messages are currently not supported to be constants.")
    )]
    NotAConstHelp {
        #[label("This command cannot run at parse time.")]
        span: Span,
    },

    #[error("{deprecation_type} deprecated.")]
    #[diagnostic(code(nu::shell::deprecated), severity(Warning))]
    DeprecationWarning {
        deprecation_type: &'static str,
        suggestion: String,
        #[label("{suggestion}")]
        span: Span,
        #[help]
        help: Option<&'static str>,
    },

    /// Invalid glob pattern
    ///
    /// ## Resolution
    ///
    /// Correct glob pattern
    #[error("Invalid glob pattern")]
    #[diagnostic(
        code(nu::shell::invalid_glob_pattern),
        help("Refer to xxx for help on nushell glob patterns.")
    )]
    InvalidGlobPattern {
        msg: String,
        #[label("{msg}")]
        span: Span,
    },

    /// Invalid unit
    ///
    /// ## Resolution
    ///
    /// Correct unit
    #[error("Invalid unit")]
    #[diagnostic(
        code(nu::shell::invalid_unit),
        help("Supported units are: {supported_units}")
    )]
    InvalidUnit {
        supported_units: String,
        #[label("encountered here")]
        span: Span,
    },

    /// Tried spreading a non-list inside a list or command call.
    ///
    /// ## Resolution
    ///
    /// Only lists can be spread inside lists and command calls. Try converting the value to a list before spreading.
    #[error("Not a list")]
    #[diagnostic(
        code(nu::shell::cannot_spread_as_list),
        help(
            "Only lists can be spread inside lists and command calls. Try converting the value to a list before spreading."
        )
    )]
    CannotSpreadAsList {
        #[label = "cannot spread value"]
        span: Span,
    },

    /// Tried spreading a non-record inside a record.
    ///
    /// ## Resolution
    ///
    /// Only records can be spread inside records. Try converting the value to a record before spreading.
    #[error("Not a record")]
    #[diagnostic(
        code(nu::shell::cannot_spread_as_record),
        help(
            "Only records can be spread inside records. Try converting the value to a record before spreading."
        )
    )]
    CannotSpreadAsRecord {
        #[label = "cannot spread value"]
        span: Span,
    },

    /// Lists are not automatically spread when calling external commands
    ///
    /// ## Resolution
    ///
    /// Use the spread operator (put a '...' before the argument)
    #[error("Lists are not automatically spread when calling external commands")]
    #[diagnostic(
        code(nu::shell::cannot_pass_list_to_external),
        help("Either convert the list to a string or use the spread operator, like so: ...{arg}")
    )]
    CannotPassListToExternal {
        arg: String,
        #[label = "Spread operator (...) is necessary to spread lists"]
        span: Span,
    },

    /// Out of bounds.
    ///
    /// ## Resolution
    ///
    /// Make sure the range is within the bounds of the input.
    #[error(
        "The selected range {left_flank}..{right_flank} is out of the bounds of the provided input"
    )]
    #[diagnostic(code(nu::shell::out_of_bounds))]
    OutOfBounds {
        left_flank: String,
        right_flank: String,
        #[label = "byte index is not a char boundary or is out of bounds of the input"]
        span: Span,
    },

    /// The config directory could not be found
    #[error("The config directory could not be found")]
    #[diagnostic(
        code(nu::shell::config_dir_not_found),
        help(
            r#"On Linux, this would be $XDG_CONFIG_HOME or $HOME/.config.
On MacOS, this would be `$HOME/Library/Application Support`.
On Windows, this would be %USERPROFILE%\AppData\Roaming"#
        )
    )]
    ConfigDirNotFound {
        #[label = "Could not find config directory"]
        span: Span,
    },

    /// XDG_CONFIG_HOME was set to an invalid path
    #[error(
        "$env.XDG_CONFIG_HOME ({xdg}) is invalid, using default config directory instead: {default}"
    )]
    #[diagnostic(
        code(nu::shell::xdg_config_home_invalid),
        help("Set XDG_CONFIG_HOME to an absolute path, or set it to an empty string to ignore it")
    )]
    InvalidXdgConfig { xdg: String, default: String },

    /// An unexpected error occurred during IR evaluation.
    ///
    /// ## Resolution
    ///
    /// This is most likely a correctness issue with the IR compiler or evaluator. Please file a
    /// bug with the minimum code needed to reproduce the issue, if possible.
    #[error("IR evaluation error: {msg}")]
    #[diagnostic(
        code(nu::shell::ir_eval_error),
        help(
            "this is a bug, please report it at https://github.com/nushell/nushell/issues/new along with the code you were running if able"
        )
    )]
    IrEvalError {
        msg: String,
        #[label = "while running this code"]
        span: Option<Span>,
    },

    #[error("OS feature is disabled: {msg}")]
    #[diagnostic(
        code(nu::shell::os_disabled),
        help("You're probably running outside an OS like a browser, we cannot support this")
    )]
    DisabledOsSupport {
        msg: String,
        #[label = "while running this code"]
        span: Span,
    },

    #[error(transparent)]
    #[diagnostic(transparent)]
    Job(#[from] JobError),

    #[error(transparent)]
    #[diagnostic(transparent)]
    ChainedError(ChainedError),
}

impl ShellError {
    pub fn external_exit_code(&self) -> Option<Spanned<i32>> {
        let (item, span) = match *self {
            Self::NonZeroExitCode { exit_code, span } => (exit_code.into(), span),
            #[cfg(unix)]
            Self::TerminatedBySignal { signal, span, .. }
            | Self::CoreDumped { signal, span, .. } => (-signal, span),
            _ => return None,
        };
        Some(Spanned { item, span })
    }

    pub fn exit_code(&self) -> Option<i32> {
        match self {
            Self::Return { .. } | Self::Break { .. } | Self::Continue { .. } => None,
            _ => self.external_exit_code().map(|e| e.item).or(Some(1)),
        }
    }

    pub fn into_full_value(
        self,
        working_set: &StateWorkingSet,
        stack: &Stack,
        span: Span,
    ) -> Value {
        let exit_code = self.external_exit_code();

        let mut record = record! {
            "msg" => Value::string(self.to_string(), span),
            "debug" => Value::string(format!("{self:?}"), span),
            "raw" => Value::error(self.clone(), span),
            "rendered" => Value::string(format_cli_error(Some(stack), working_set, &self, Some("nu::shell::error")), span),
            "json" => Value::string(serde_json::to_string(&self).expect("Could not serialize error"), span),
        };

        if let Some(code) = exit_code {
            record.push("exit_code", Value::int(code.item.into(), code.span));
        }

        Value::record(record, span)
    }

    // TODO: Implement as From trait
    pub fn wrap(self, working_set: &StateWorkingSet, span: Span) -> ParseError {
        let msg = format_cli_error(None, working_set, &self, None);
        ParseError::LabeledError(
            msg,
            "Encountered error during parse-time evaluation".into(),
            span,
        )
    }

    /// Convert self error to a [`ShellError::ChainedError`] variant.
    pub fn into_chained(self, span: Span) -> Self {
        Self::ChainedError(match self {
            Self::ChainedError(inner) => ChainedError::new_chained(inner, span),
            other => {
                // If it's not already a chained error, it could have more errors below
                // it that we want to chain together
                let error = other.clone();
                let mut now = ChainedError::new(other, span);
                if let Some(related) = error.related() {
                    let mapped = related
                        .map(|s| {
                            let shellerror: Self = Self::from_diagnostic(s);
                            shellerror
                        })
                        .collect::<Vec<_>>();
                    if !mapped.is_empty() {
                        now.sources = [now.sources, mapped].concat();
                    };
                }
                now
            }
        })
    }

    pub fn from_diagnostic(diag: &(impl miette::Diagnostic + ?Sized)) -> Self {
        Self::LabeledError(LabeledError::from_diagnostic(diag).into())
    }
}

impl FromValue for ShellError {
    fn from_value(v: Value) -> Result<Self, ShellError> {
        let from_type = v.get_type();
        match v {
            Value::Error { error, .. } => Ok(*error),
            // Also let it come from the into_full_value record.
            Value::Record {
                val, internal_span, ..
            } => Self::from_value(
                (*val)
                    .get("raw")
                    .ok_or(ShellError::CantConvert {
                        to_type: Self::expected_type().to_string(),
                        from_type: from_type.to_string(),
                        span: internal_span,
                        help: None,
                    })?
                    .clone(),
            ),
            Value::Nothing { internal_span } => Ok(Self::GenericError {
                error: "error".into(),
                msg: "is nothing".into(),
                span: Some(internal_span),
                help: None,
                inner: vec![],
            }),
            _ => Err(ShellError::CantConvert {
                to_type: Self::expected_type().to_string(),
                from_type: v.get_type().to_string(),
                span: v.span(),
                help: None,
            }),
        }
    }
}

impl From<Box<dyn std::error::Error>> for ShellError {
    fn from(error: Box<dyn std::error::Error>) -> ShellError {
        ShellError::GenericError {
            error: format!("{error:?}"),
            msg: error.to_string(),
            span: None,
            help: None,
            inner: vec![],
        }
    }
}

impl From<Box<dyn std::error::Error + Send + Sync>> for ShellError {
    fn from(error: Box<dyn std::error::Error + Send + Sync>) -> ShellError {
        ShellError::GenericError {
            error: format!("{error:?}"),
            msg: error.to_string(),
            span: None,
            help: None,
            inner: vec![],
        }
    }
}

impl From<super::LabeledError> for ShellError {
    fn from(error: super::LabeledError) -> Self {
        ShellError::LabeledError(Box::new(error))
    }
}

/// `ShellError` always serializes as [`LabeledError`].
impl Serialize for ShellError {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: serde::Serializer,
    {
        LabeledError::from_diagnostic(self).serialize(serializer)
    }
}

/// `ShellError` always deserializes as if it were [`LabeledError`], resulting in a
/// [`ShellError::LabeledError`] variant.
impl<'de> Deserialize<'de> for ShellError {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::Deserializer<'de>,
    {
        LabeledError::deserialize(deserializer).map(ShellError::from)
    }
}

#[test]
fn shell_error_serialize_roundtrip() {
    // Ensure that we can serialize and deserialize `ShellError`, and check that it basically would
    // look the same
    let original_error = ShellError::CantConvert {
        span: Span::new(100, 200),
        to_type: "Foo".into(),
        from_type: "Bar".into(),
        help: Some("this is a test".into()),
    };
    println!("orig_error = {original_error:#?}");

    let serialized =
        serde_json::to_string_pretty(&original_error).expect("serde_json::to_string_pretty failed");
    println!("serialized = {serialized}");

    let deserialized: ShellError =
        serde_json::from_str(&serialized).expect("serde_json::from_str failed");
    println!("deserialized = {deserialized:#?}");

    // We don't expect the deserialized error to be the same as the original error, but its miette
    // properties should be comparable
    assert_eq!(original_error.to_string(), deserialized.to_string());

    assert_eq!(
        original_error.code().map(|c| c.to_string()),
        deserialized.code().map(|c| c.to_string())
    );

    let orig_labels = original_error
        .labels()
        .into_iter()
        .flatten()
        .collect::<Vec<_>>();
    let deser_labels = deserialized
        .labels()
        .into_iter()
        .flatten()
        .collect::<Vec<_>>();

    assert_eq!(orig_labels, deser_labels);

    assert_eq!(
        original_error.help().map(|c| c.to_string()),
        deserialized.help().map(|c| c.to_string())
    );
}

#[cfg(test)]
mod test {
    use super::*;

    impl From<std::io::Error> for ShellError {
        fn from(_: std::io::Error) -> ShellError {
            unimplemented!(
                "This implementation is defined in the test module to ensure no other implementation exists."
            )
        }
    }

    impl From<Spanned<std::io::Error>> for ShellError {
        fn from(_: Spanned<std::io::Error>) -> Self {
            unimplemented!(
                "This implementation is defined in the test module to ensure no other implementation exists."
            )
        }
    }

    impl From<ShellError> for std::io::Error {
        fn from(_: ShellError) -> Self {
            unimplemented!(
                "This implementation is defined in the test module to ensure no other implementation exists."
            )
        }
    }
}