artichoke_backend/
fmt.rs

1//! Utilities for interfacing [`std::fmt`] with Artichoke's exception types.
2
3use std::borrow::Cow;
4use std::error;
5use std::fmt;
6
7use spinoso_exception::Fatal;
8
9use crate::Artichoke;
10use crate::core::{ClassRegistry, TryConvertMut};
11use crate::error::{Error, RubyException};
12use crate::sys;
13
14/// Error type which converts a [`fmt::Error`] into an Artichoke [`Error`].
15///
16/// This error type can also be used to convert generic [`fmt::Error`] into an
17/// [`Error`], such as when formatting integers with [`write!`].
18///
19/// This  error type wraps a [`fmt::Error`].
20///
21/// # Examples
22///
23/// ```
24/// use std::fmt::Write;
25/// # use artichoke_backend::Error;;
26/// # use artichoke_backend::fmt::WriteError;
27///
28/// fn task() -> Result<String, Error> {
29///     let mut buf = String::new();
30///     write!(&mut buf, "success!").map_err(WriteError::from)?;
31///     Ok(buf)
32/// }
33/// # task().unwrap();
34/// ```
35#[derive(Debug, Clone, Copy)]
36pub struct WriteError(fmt::Error);
37
38impl From<fmt::Error> for WriteError {
39    fn from(err: fmt::Error) -> Self {
40        Self(err)
41    }
42}
43
44impl From<WriteError> for fmt::Error {
45    fn from(err: WriteError) -> Self {
46        err.into_inner()
47    }
48}
49
50impl WriteError {
51    #[inline]
52    #[must_use]
53    pub fn into_inner(self) -> fmt::Error {
54        self.0
55    }
56}
57
58impl fmt::Display for WriteError {
59    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
60        f.write_str("Unable to write message into destination")
61    }
62}
63
64impl error::Error for WriteError {
65    #[inline]
66    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
67        Some(&self.0)
68    }
69}
70
71impl RubyException for WriteError {
72    #[inline]
73    fn message(&self) -> Cow<'_, [u8]> {
74        Cow::Borrowed(b"Unable to write message into destination")
75    }
76
77    #[inline]
78    fn name(&self) -> Cow<'_, str> {
79        "fatal".into()
80    }
81
82    fn vm_backtrace(&self, interp: &mut Artichoke) -> Option<Vec<Vec<u8>>> {
83        let _ = interp;
84        None
85    }
86
87    fn as_mrb_value(&self, interp: &mut Artichoke) -> Option<sys::mrb_value> {
88        let message = interp.try_convert_mut(self.message()).ok()?;
89        let value = interp.new_instance::<Fatal>(&[message]).ok().flatten()?;
90        Some(value.inner())
91    }
92}
93
94impl From<WriteError> for Error {
95    #[inline]
96    fn from(exception: WriteError) -> Self {
97        let err: Box<dyn RubyException> = Box::new(exception);
98        Self::from(err)
99    }
100}
artichoke_backend/fmt.rs

artichoke_backend/
fmt.rs
