1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373
//! Error traits and error kinds
#[cfg(doc)]
use super::*;
use std::borrow::Cow;
use std::error::Error;
use std::fmt;
use std::ops::{Deref, DerefMut};
/// Kinds of [`MachineError`]s
#[derive(Copy, Clone, PartialEq, Eq, Hash, Default, Debug)]
pub enum MachineErrorKind {
/// Out-of-memory error
Memory,
/// Syntax error during compilation (see [`Compile::compile`])
Syntax,
/// Execution limit error
ExecLimit,
/// Generic runtime error (see [`Function::call`])
Runtime,
/// Unexpected value(s) (e.g. wrong type or wrong count of return values)
Data,
/// Error kind unknown
#[default]
Unknown,
}
/// Unboxed version of [`MachineError`]
///
/// All fields of this struct may be accessed through `MachineError` as well
/// (due to [`Deref`] and [`DerefMut`] implementation by `MachineError).
#[derive(Clone, Default)]
#[non_exhaustive]
pub struct MachineErrorUnboxed {
/// Kind of runtime error
pub kind: MachineErrorKind,
/// Error message
pub message: Option<String>,
/// Backtrace (multiple lines, without trailing newline)
pub machine_backtrace: Option<String>,
/// Chunk name already included in message?
pub message_incl_chunk_name: bool,
/// Chunk name
pub chunk_name: Option<String>,
/// Position already included in message?
pub message_incl_pos: bool,
/// Line number
pub line: Option<usize>,
/// Column number (in UTF-8 codepoints)
pub column: Option<usize>,
/// Byte position
pub position: Option<usize>,
}
/// Runtime or compiler errors that may refer to a specific position in code
#[derive(Clone, Default)]
pub struct MachineError {
/// Boxed struct containing all fields
/// (accessible through [`Deref`] and [`DerefMut`])
pub boxed: Box<MachineErrorUnboxed>,
}
impl Deref for MachineError {
type Target = MachineErrorUnboxed;
fn deref(&self) -> &Self::Target {
&self.boxed
}
}
impl DerefMut for MachineError {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.boxed
}
}
impl MachineError {
/// Creates a new `MachineError` that may also be used as a builder
pub fn new() -> Self {
Default::default()
}
/// Builder-style method to set the [`MachineErrorKind`]
pub fn set_kind(mut self, kind: MachineErrorKind) -> Self {
self.kind = kind;
self
}
/// Builder-style method to set an error [`message`]
///
/// [`message`]: MachineErrorUnboxed::message
pub fn set_message(mut self, message: String) -> Self {
self.message = Some(message);
self
}
/// Builder-style method to set an error [`message`] using a `str` slice
///
/// [`message`]: MachineErrorUnboxed::message
pub fn set_message_str(mut self, message: &str) -> Self {
self.message = Some(message.to_owned());
self
}
/// Builder-style method to set an error [`message`] [option]
///
/// [`message`]: MachineErrorUnboxed::message
/// [option]: Option
pub fn set_message_opt(mut self, message: Option<String>) -> Self {
self.message = message;
self
}
/// Builder-style method to set [`machine_backtrace`]
///
/// [`machine_backtrace`]: MachineErrorUnboxed::machine_backtrace
pub fn set_machine_backtrace(mut self, machine_backtrace: String) -> Self {
self.machine_backtrace = Some(machine_backtrace);
self
}
/// Builder-style method to set a [`machine_backtrace`] [option]
///
/// [`machine_backtrace`]: MachineErrorUnboxed::machine_backtrace
/// [option]: Option
pub fn set_machine_backtrace_opt(mut self, machine_backtrace: Option<String>) -> Self {
self.machine_backtrace = machine_backtrace;
self
}
/// Builder-style method to set [`message_incl_chunk_name`] to `true`
///
/// [`message_incl_chunk_name`]: MachineErrorUnboxed::message_incl_chunk_name
pub fn set_message_incl_chunk_name(mut self) -> Self {
self.message_incl_chunk_name = true;
self
}
/// Builder-style method to set [`message_incl_chunk_name`] to `bool`
///
/// [`message_incl_chunk_name`]: MachineErrorUnboxed::message_incl_chunk_name
pub fn set_message_incl_chunk_name_bool(mut self, message_incl_chunk_name: bool) -> Self {
self.message_incl_chunk_name = message_incl_chunk_name;
self
}
/// Builder-style method to set [`chunk_name`]
///
/// [`chunk_name`]: MachineErrorUnboxed::chunk_name
pub fn set_chunk_name(mut self, chunk_name: String) -> Self {
self.chunk_name = Some(chunk_name);
self
}
/// Builder-style method to set [`chunk_name`] [option]
///
/// [`chunk_name`]: MachineErrorUnboxed::chunk_name
/// [option]: Option
pub fn set_chunk_name_opt(mut self, chunk_name: Option<String>) -> Self {
self.chunk_name = chunk_name;
self
}
/// Builder-style method to set [`message_incl_pos`] to `true`
///
/// [`message_incl_pos`]: MachineErrorUnboxed::message_incl_pos
pub fn set_message_incl_pos(mut self) -> Self {
self.message_incl_pos = true;
self
}
/// Builder-style method to set [`message_incl_pos`] to a `bool`
///
/// [`message_incl_pos`]: MachineErrorUnboxed::message_incl_pos
pub fn set_message_incl_pos_bool(mut self, message_incl_pos: bool) -> Self {
self.message_incl_pos = message_incl_pos;
self
}
/// Builder-style method to set [`line`]
///
/// [`line`]: MachineErrorUnboxed::line
pub fn set_line(mut self, line: usize) -> Self {
self.line = Some(line);
self
}
/// Builder-style method to set [`line`] [option]
///
/// [`line`]: MachineErrorUnboxed::line
/// [option]: Option
pub fn set_line_opt(mut self, line: Option<usize>) -> Self {
self.line = line;
self
}
/// Builder-style method to set [`column`]
///
/// [`column`]: MachineErrorUnboxed::column
pub fn set_column(mut self, column: usize) -> Self {
self.column = Some(column);
self
}
/// Builder-style method to set [`column`] [option]
///
/// [`column`]: MachineErrorUnboxed::column
/// [option]: Option
pub fn set_column_opt(mut self, column: Option<usize>) -> Self {
self.column = column;
self
}
/// Builder-style method to set [`position`]
///
/// [`position`]: MachineErrorUnboxed::position
pub fn set_position(mut self, position: usize) -> Self {
self.position = Some(position);
self
}
/// Builder-style method to set [`position`] [option]
///
/// [`position`]: MachineErrorUnboxed::position
/// [option]: Option
pub fn set_position_opt(mut self, position: Option<usize>) -> Self {
self.position = position;
self
}
}
impl Error for MachineError {}
impl fmt::Display for MachineError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self.kind {
MachineErrorKind::Memory => write!(f, "VM memory exhausted")?,
MachineErrorKind::Syntax => write!(f, "syntax error in code for VM")?,
MachineErrorKind::ExecLimit => write!(f, "VM execution limit exhausted")?,
MachineErrorKind::Runtime => write!(f, "runtime error in VM")?,
MachineErrorKind::Data => write!(f, "unexpected data from VM")?,
_ => write!(f, "VM error")?,
}
let mut chunk_name_written = false;
if !self.message_incl_chunk_name {
if let Some(ref chunk_name) = self.chunk_name {
write!(f, " in chunk \"{}\"", chunk_name)?;
chunk_name_written = true;
}
}
if !self.message_incl_pos {
if let Some(line) = self.line {
write!(
f,
"{} line {}",
if chunk_name_written { ", " } else { " in" },
line
)?;
if let Some(column) = self.column {
write!(f, ", column {}", column)?;
}
} else if let Some(position) = self.position {
write!(f, ", at byte position {}", position)?;
}
}
if let Some(msg) = &self.message {
write!(f, ": {}", msg)?;
}
Ok(())
}
}
impl fmt::Debug for MachineError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("MachineError")
.field("kind", &self.kind)
.field("message", &self.message)
.field("message_incl_pos", &self.message_incl_pos)
.field("chunk_name", &self.chunk_name)
.field("line", &self.line)
.field("column", &self.column)
.field("position", &self.position)
.finish_non_exhaustive()
}
}
/// Error indicating that [`Machine::Datum`] had an unexpected (dynamic) type
///
/// See also [`types`] module.
///
/// For convenience, this error type can be converted into a [`MachineError`].
#[derive(Debug)]
pub struct TypeMismatch {
/// Error description
message: Cow<'static, str>,
}
impl TypeMismatch {
/// Create new `TypeMismatch` without specific message
pub const fn new() -> Self {
TypeMismatch {
message: Cow::Borrowed("dynamic type mismatch (no details available)"),
}
}
/// Create new `TypeMismatch` from owned [`String`]
pub fn with_msg(message: String) -> Self {
TypeMismatch {
message: Cow::Owned(message),
}
}
/// Create new `TypeMismatch` with static error message
pub const fn with_static_msg(message: &'static str) -> Self {
TypeMismatch {
message: Cow::Borrowed(message),
}
}
}
impl fmt::Display for TypeMismatch {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.write_str(&self.message)
}
}
impl Error for TypeMismatch {}
impl From<TypeMismatch> for MachineError {
fn from(datum_err: TypeMismatch) -> Self {
MachineError::new()
.set_kind(MachineErrorKind::Data)
.set_message(datum_err.to_string())
}
}
/// Error type when using [`TryFrom`]/[`TryInto`] to convert a
/// [`Machine::Datum`] into a particular type
///
/// See also [`types`] module.
///
/// Since this type contains the original `Datum`, it might not be
/// `Send + Sync + 'static`. `DatumConversionFailure` also does not implement
/// [`std::error::Error`]. You can convert this error into [`TypeMismatch`]
/// (or extract the [`error`] field), which implements `std::error::Error` and
/// is `Send + Sync + 'static`.
///
/// For convenience, values of this type can also be directly converted into a
/// [`MachineError`].
///
/// [`error`]: DatumConversionFailure::error
pub struct DatumConversionFailure<D> {
/// Original datum that could not be converted
pub original: D,
/// Error description
pub error: TypeMismatch,
}
impl<D> DatumConversionFailure<D> {
/// Create new `DatumConversionFailure` with given [`TypeMismatch`] error
pub fn new(original: D, error: TypeMismatch) -> Self {
DatumConversionFailure { original, error }
}
/// Create new `DatumConversionFailure` with owned [`String`] error message
pub fn with_msg(original: D, message: String) -> Self {
DatumConversionFailure::new(original, TypeMismatch::with_msg(message))
}
/// Create new `DatumConversionFailure` with static error message
pub fn with_static_msg(original: D, message: &'static str) -> Self {
DatumConversionFailure::new(original, TypeMismatch::with_static_msg(message))
}
}
impl<D> fmt::Debug for DatumConversionFailure<D> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("DatumConversionFailure")
.field("error", &self.error)
.finish_non_exhaustive()
}
}
impl<D> From<DatumConversionFailure<D>> for TypeMismatch {
fn from(failure: DatumConversionFailure<D>) -> Self {
failure.error
}
}
impl<D> From<DatumConversionFailure<D>> for MachineError {
fn from(failure: DatumConversionFailure<D>) -> Self {
MachineError::new()
.set_kind(MachineErrorKind::Data)
.set_message(TypeMismatch::from(failure).to_string())
}
}