use crate::path::Path;
use serde::{de, ser};
use std::error;
use std::fmt::{self, Debug, Display};
use std::io;
use std::result;
use std::str;
use std::string;
use std::sync::Arc;
use yaml_rust::emitter;
use yaml_rust::scanner::{self, Marker, ScanError};
/// An error that happened serializing or deserializing YAML data.
pub struct Error(Box<ErrorImpl>);
/// Alias for a `Result` with the error type `serde_yaml::Error`.
pub type Result<T> = result::Result<T, Error>;
#[derive(Debug)]
pub enum ErrorImpl {
Message(String, Option<Pos>),
Emit(emitter::EmitError),
Scan(scanner::ScanError),
Io(io::Error),
Utf8(str::Utf8Error),
FromUtf8(string::FromUtf8Error),
EndOfStream,
MoreThanOneDocument,
RecursionLimitExceeded,
Shared(Arc<ErrorImpl>),
}
#[derive(Debug)]
pub struct Pos {
marker: Marker,
path: String,
}
/// The input location that an error occured.
#[derive(Debug)]
pub struct Location {
index: usize,
line: usize,
column: usize,
}
impl Location {
/// The byte index of the error
pub fn index(&self) -> usize {
self.index
}
/// The line of the error
pub fn line(&self) -> usize {
self.line
}
/// The column of the error
pub fn column(&self) -> usize {
self.column
}
// This is to keep decoupled with the yaml crate
#[doc(hidden)]
fn from_marker(marker: &Marker) -> Self {
Location {
// `col` returned from the `yaml` crate is 0-indexed but all error messages add + 1 to this value
column: marker.col() + 1,
index: marker.index(),
line: marker.line(),
}
}
}
impl Error {
/// Returns the Location from the error if one exists.
///
/// Not all types of errors have a location so this can return `None`.
///
/// # Examples
///
/// ```
/// # use serde_yaml::{Value, Error};
/// #
/// // The `@` character as the first character makes this invalid yaml
/// let invalid_yaml: Result<Value, Error> = serde_yaml::from_str("@invalid_yaml");
///
/// let location = invalid_yaml.unwrap_err().location().unwrap();
///
/// assert_eq!(location.line(), 1);
/// assert_eq!(location.column(), 1);
/// ```
pub fn location(&self) -> Option<Location> {
match self.0.as_ref() {
ErrorImpl::Message(_, Some(pos)) => Some(Location::from_marker(&pos.marker)),
ErrorImpl::Scan(scan) => Some(Location::from_marker(scan.marker())),
_ => None,
}
}
}
pub(crate) fn end_of_stream() -> Error {
Error(Box::new(ErrorImpl::EndOfStream))
}
pub(crate) fn more_than_one_document() -> Error {
Error(Box::new(ErrorImpl::MoreThanOneDocument))
}
pub(crate) fn io(err: io::Error) -> Error {
Error(Box::new(ErrorImpl::Io(err)))
}
pub(crate) fn emitter(err: emitter::EmitError) -> Error {
Error(Box::new(ErrorImpl::Emit(err)))
}
pub(crate) fn scanner(err: scanner::ScanError) -> Error {
Error(Box::new(ErrorImpl::Scan(err)))
}
pub(crate) fn str_utf8(err: str::Utf8Error) -> Error {
Error(Box::new(ErrorImpl::Utf8(err)))
}
pub(crate) fn string_utf8(err: string::FromUtf8Error) -> Error {
Error(Box::new(ErrorImpl::FromUtf8(err)))
}
pub(crate) fn recursion_limit_exceeded() -> Error {
Error(Box::new(ErrorImpl::RecursionLimitExceeded))
}
pub(crate) fn shared(shared: Arc<ErrorImpl>) -> Error {
Error(Box::new(ErrorImpl::Shared(shared)))
}
pub(crate) fn fix_marker(mut error: Error, marker: Marker, path: Path) -> Error {
if let ErrorImpl::Message(_, none @ None) = error.0.as_mut() {
*none = Some(Pos {
marker,
path: path.to_string(),
});
}
error
}
impl Error {
pub(crate) fn shared(self) -> Arc<ErrorImpl> {
if let ErrorImpl::Shared(err) = *self.0 {
err
} else {
Arc::from(self.0)
}
}
}
impl error::Error for Error {
fn source(&self) -> Option<&(dyn error::Error + 'static)> {
self.0.source()
}
}
impl Display for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
self.0.display(f)
}
}
// Remove two layers of verbosity from the debug representation. Humans often
// end up seeing this representation because it is what unwrap() shows.
impl Debug for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
self.0.debug(f)
}
}
impl ser::Error for Error {
fn custom<T: Display>(msg: T) -> Self {
Error(Box::new(ErrorImpl::Message(msg.to_string(), None)))
}
}
impl de::Error for Error {
fn custom<T: Display>(msg: T) -> Self {
Error(Box::new(ErrorImpl::Message(msg.to_string(), None)))
}
}
impl ErrorImpl {
fn source(&self) -> Option<&(dyn error::Error + 'static)> {
match self {
ErrorImpl::Scan(err) => Some(err),
ErrorImpl::Io(err) => Some(err),
ErrorImpl::Utf8(err) => Some(err),
ErrorImpl::FromUtf8(err) => Some(err),
ErrorImpl::Shared(err) => err.source(),
_ => None,
}
}
fn display(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
ErrorImpl::Message(msg, None) => Display::fmt(msg, f),
ErrorImpl::Message(msg, Some(Pos { marker, path })) => {
if path == "." {
write!(f, "{}", ScanError::new(*marker, msg))
} else {
write!(f, "{}: {}", path, ScanError::new(*marker, msg))
}
}
ErrorImpl::Emit(emitter::EmitError::FmtError(_)) => f.write_str("yaml-rust fmt error"
),
ErrorImpl::Emit(emitter::EmitError::BadHashmapKey) => f.write_str("bad hash map key"),
ErrorImpl::Scan(err) => Display::fmt(err, f),
ErrorImpl::Io(err) => Display::fmt(err, f),
ErrorImpl::Utf8(err) => Display::fmt(err, f),
ErrorImpl::FromUtf8(err) => Display::fmt(err, f),
ErrorImpl::EndOfStream => f.write_str("EOF while parsing a value"),
ErrorImpl::MoreThanOneDocument => f.write_str(
"deserializing from YAML containing more than one document is not supported",
),
ErrorImpl::RecursionLimitExceeded => f.write_str("recursion limit exceeded"),
ErrorImpl::Shared(err) => err.display(f),
}
}
fn debug(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
ErrorImpl::Message(msg, pos) => f.debug_tuple("Message").field(msg).field(pos).finish(),
ErrorImpl::Emit(emit) => f.debug_tuple("Emit").field(emit).finish(),
ErrorImpl::Scan(scan) => f.debug_tuple("Scan").field(scan).finish(),
ErrorImpl::Io(io) => f.debug_tuple("Io").field(io).finish(),
ErrorImpl::Utf8(utf8) => f.debug_tuple("Utf8").field(utf8).finish(),
ErrorImpl::FromUtf8(from_utf8) => f.debug_tuple("FromUtf8").field(from_utf8).finish(),
ErrorImpl::EndOfStream => f.debug_tuple("EndOfStream").finish(),
ErrorImpl::MoreThanOneDocument => f.debug_tuple("MoreThanOneDocument").finish(),
ErrorImpl::RecursionLimitExceeded => f.debug_tuple("RecursionLimitExceeded").finish(),
ErrorImpl::Shared(err) => err.debug(f),
}
}
}
