maraiah: add FromStr for cbitfield

master
an 2019-07-03 01:16:35 -04:00
parent 68bfd417b5
commit bb173b47e3
3 changed files with 94 additions and 1 deletions

View File

@ -1,5 +1,6 @@
#![doc(hidden)]
/// A wrapper for `bitflags!` which adds a `FromStr` implementation.
#[macro_export]
macro_rules! c_bitfield
{
@ -22,6 +23,65 @@ macro_rules! c_bitfield
)+
}
}
#[allow(unused_qualifications)]
impl std::str::FromStr for $t
{
type Err = $crate::err::ParseFlagError;
fn from_str(s: &str) -> Result<Self, Self::Err>
{
let mut flags = $t::empty();
for s in s.split('|') {
match s {
$(
stringify!($f) => flags.insert($t::$f),
)+
"(none)" => (),
_ => return Err(Self::Err::new(stringify!($t)))
}
}
Ok(flags)
}
}
}
}
#[cfg(test)]
mod test
{
use crate::err::ParseFlagError;
use std::str::FromStr;
c_bitfield! {
pub struct TestFlag: u16 {
ZERO = 0,
ONE = 1,
TWO = 2,
}
}
#[test]
fn c_bitfield()
{
assert_eq!(TestFlag::from_bits(0), Some(TestFlag::empty()));
assert_eq!(TestFlag::from_bits(1), Some(TestFlag::ZERO));
assert_eq!(TestFlag::from_bits(2), Some(TestFlag::ONE));
assert_eq!(TestFlag::from_bits(4), Some(TestFlag::TWO));
assert_eq!(TestFlag::from_bits(8), None);
assert_eq!(TestFlag::from_str("(none)"), Ok(TestFlag::empty()));
assert_eq!(TestFlag::from_str("ZERO"), Ok(TestFlag::ZERO));
assert_eq!(TestFlag::from_str("ONE"), Ok(TestFlag::ONE));
assert_eq!(TestFlag::from_str("TWO"), Ok(TestFlag::TWO));
assert_eq!(TestFlag::from_str("ZERO|ONE|TWO"), Ok(TestFlag::all()));
assert_eq!(TestFlag::from_str("TWO|ZERO|ONE"), Ok(TestFlag::all()));
assert_eq!(TestFlag::from_str("ONE|ONE|ONE"), Ok(TestFlag::ONE));
assert_eq!(TestFlag::from_str("(none)|(none)"), Ok(TestFlag::empty()));
assert_eq!(TestFlag::from_str("(none)|ONE"), Ok(TestFlag::ONE));
assert_eq!(TestFlag::from_str("THREE"),
Err(ParseFlagError::new("TestFlag")));
}
}

View File

@ -76,7 +76,9 @@ macro_rules! c_enum
fn from_str(s: &str) -> Result<Self, Self::Err>
{
match s {
$(stringify!($en) => Ok($t::$en),)+
$(
stringify!($en) => Ok($t::$en),
)+
_ => Err(Self::Err::new(stringify!($t)))
}
}

View File

@ -71,6 +71,24 @@ impl ParseEnumError
}
}
impl ParseFlagError
{
/// Returns an `Error` with a message for flag parsing errata.
///
/// # Examples
///
/// ```
/// use maraiah::err::ParseFlagError;
///
/// assert_eq!(format!("{}", ParseFlagError::new("TypeName")),
/// "could not parse TypeName");
/// ```
pub fn new(t: &'static str) -> Self
{
Self(t)
}
}
impl ReprError
{
/// Returns an `Error` with a message for representation errata.
@ -91,6 +109,7 @@ impl ReprError
impl Fail for ErrMsg {}
impl Fail for ParseEnumError {}
impl Fail for ParseFlagError {}
impl Fail for ReprError {}
impl fmt::Display for ParseEnumError
@ -101,6 +120,14 @@ impl fmt::Display for ParseEnumError
}
}
impl fmt::Display for ParseFlagError
{
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
{
write!(f, "could not parse {}", self.0)
}
}
impl fmt::Display for ReprError
{
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
@ -124,6 +151,10 @@ struct ErrMsg(&'static str);
#[derive(Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub struct ParseEnumError(&'static str);
/// A parser error for a bit field.
#[derive(Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub struct ParseFlagError(&'static str);
/// A representation error for an integer.
#[derive(Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub struct ReprError(&'static str, i64);