bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Refactored FormattingOptions to use a bitmask for storing flags

Browse source
This commit is contained in:
Elias Holzmann 2024-02-16 03:42:03 +01:00
parent 5b236555d2
commit 832a5f292f
2 changed files with 52 additions and 54 deletions
Download patch file Download diff file Expand all files Collapse all files

90
library/core/src/fmt/mod.rs
View file

@ -288,14 +288,11 @@ pub enum DebugAsHex {
#[derive(Copy, Clone, Debug, PartialEq, Eq, Default)]
#[unstable(feature = "formatting_options", issue = "118117")]
pub struct FormattingOptions {
sign: Option<Sign>,
sign_aware_zero_pad: bool,
alternate: bool,
flags: u32,
fill: char,
align: Option<Alignment>,
width: Option<usize>,
precision: Option<usize>,
debug_as_hex: Option<DebugAsHex>,
}
impl FormattingOptions {
@ -312,14 +309,11 @@ impl FormattingOptions {
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn new() -> Self {
Self {
sign: None,
sign_aware_zero_pad: false,
alternate: false,
flags: 0,
fill: ' ',
align: None,
width: None,
precision: None,
debug_as_hex: None,
}
}
@ -333,7 +327,12 @@ impl FormattingOptions {
/// - `-`: Currently not used
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn sign(&mut self, sign: Option<Sign>) -> &mut Self {
self.sign = sign;
self.flags = self.flags & !(1 << rt::Flag::SignMinus as u32 | 1 << rt::Flag::SignPlus as u32);
match sign {
None => {},
Some(Sign::Plus) => self.flags |= 1 << rt::Flag::SignPlus as u32,
Some(Sign::Minus) => self.flags |= 1 << rt::Flag::SignMinus as u32,
}
self
}
/// Sets or unsets the `0` flag.
@ -341,7 +340,11 @@ impl FormattingOptions {
/// This is used to indicate for integer formats that the padding to width should both be done with a 0 character as well as be sign-aware
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn sign_aware_zero_pad(&mut self, sign_aware_zero_pad: bool) -> &mut Self {
self.sign_aware_zero_pad = sign_aware_zero_pad;
if sign_aware_zero_pad {
self.flags |= 1 << rt::Flag::SignAwareZeroPad as u32
} else {
self.flags &= !(1 << rt::Flag::SignAwareZeroPad as u32)
}
self
}
/// Sets or unsets the `#` flag.
@ -354,7 +357,11 @@ impl FormattingOptions {
/// - [`Binary`] - precedes the argument with a `0o`
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn alternate(&mut self, alternate: bool) -> &mut Self {
self.alternate = alternate;
if alternate {
self.flags |= 1 << rt::Flag::Alternate as u32
} else {
self.flags &= !(1 << rt::Flag::Alternate as u32)
}
self
}
/// Sets the fill character.
@ -406,24 +413,36 @@ impl FormattingOptions {
/// hexadecimal or normal integers
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn debug_as_hex(&mut self, debug_as_hex: Option<DebugAsHex>) -> &mut Self {
self.debug_as_hex = debug_as_hex;
self.flags = self.flags & !(1 << rt::Flag::DebugUpperHex as u32 | 1 << rt::Flag::DebugLowerHex as u32);
match debug_as_hex {
None => {},
Some(DebugAsHex::Upper) => self.flags |= 1 << rt::Flag::DebugUpperHex as u32,
Some(DebugAsHex::Lower) => self.flags |= 1 << rt::Flag::DebugLowerHex as u32,
}
self
}
/// Returns the current sign (the `+` or the `-` flag).
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn get_sign(&self) -> Option<Sign> {
self.sign
const SIGN_PLUS_BITFIELD: u32 = 1 << rt::Flag::SignPlus as u32;
const SIGN_MINUS_BITFIELD: u32 = 1 << rt::Flag::SignMinus as u32;
match self.flags & ((1 << rt::Flag::SignPlus as u32) | (1 << rt::Flag::SignMinus as u32)) {
SIGN_PLUS_BITFIELD => Some(Sign::Plus),
SIGN_MINUS_BITFIELD => Some(Sign::Minus),
0 => None,
_ => panic!("Invalid sign bits set in flags"),
}
}
/// Returns the current `0` flag.
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn get_sign_aware_zero_pad(&self) -> bool {
self.sign_aware_zero_pad
self.flags & (1 << rt::Flag::SignAwareZeroPad as u32) != 0
}
/// Returns the current `#` flag.
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn get_alternate(&self) -> bool {
self.alternate
self.flags & (1 << rt::Flag::Alternate as u32) != 0
}
/// Returns the current fill character.
#[unstable(feature = "formatting_options", issue = "118117")]
@ -448,7 +467,14 @@ impl FormattingOptions {
/// Returns the current precision.
#[unstable(feature = "formatting_options", issue = "118117")]
pub const fn get_debug_as_hex(&self) -> Option<DebugAsHex> {
self.debug_as_hex
const DEBUG_UPPER_BITFIELD: u32 = 1 << rt::Flag::DebugUpperHex as u32;
const DEBUG_LOWER_BITFIELD: u32 = 1 << rt::Flag::DebugLowerHex as u32;
match self.flags & ((1 << rt::Flag::DebugUpperHex as u32) | (1 << rt::Flag::DebugLowerHex as u32)) {
DEBUG_UPPER_BITFIELD => Some(DebugAsHex::Upper),
DEBUG_LOWER_BITFIELD => Some(DebugAsHex::Lower),
0 => None,
_ => panic!("Invalid hex debug bits set in flags"),
}
}
/// Creates a [`Formatter`] that writes its output to the given [`Write`] trait.
@ -463,37 +489,13 @@ impl FormattingOptions {
#[unstable(feature = "fmt_internals", reason = "internal to standard library", issue = "none")]
/// Flags for formatting
pub fn flags(&mut self, flags: u32) {
self.sign = if flags & (1 << rt::Flag::SignPlus as u32) != 0 {
Some(Sign::Plus)
} else if flags & (1 << rt::Flag::SignMinus as u32) != 0 {
Some(Sign::Minus)
} else {
None
};
self.alternate = (flags & (1 << rt::Flag::Alternate as u32)) != 0;
self.sign_aware_zero_pad = (flags & (1 << rt::Flag::SignAwareZeroPad as u32)) != 0;
self.debug_as_hex = if flags & (1 << rt::Flag::DebugLowerHex as u32) != 0 {
Some(DebugAsHex::Lower)
} else if flags & (1 << rt::Flag::DebugUpperHex as u32) != 0 {
Some(DebugAsHex::Upper)
} else {
None
};
self.flags = flags
}
#[doc(hidden)]
#[unstable(feature = "fmt_internals", reason = "internal to standard library", issue = "none")]
/// Flags for formatting
pub fn get_flags(&self) -> u32 {
<bool as Into<u32>>::into(self.get_sign() == Some(Sign::Plus)) << rt::Flag::SignPlus as u32
| <bool as Into<u32>>::into(self.get_sign() == Some(Sign::Minus))
<< rt::Flag::SignMinus as u32
| <bool as Into<u32>>::into(self.get_alternate()) << rt::Flag::Alternate as u32
| <bool as Into<u32>>::into(self.get_sign_aware_zero_pad())
<< rt::Flag::SignAwareZeroPad as u32
| <bool as Into<u32>>::into(self.debug_as_hex == Some(DebugAsHex::Lower))
<< rt::Flag::DebugLowerHex as u32
| <bool as Into<u32>>::into(self.debug_as_hex == Some(DebugAsHex::Upper))
<< rt::Flag::DebugUpperHex as u32
self.flags
}
}
@ -2161,11 +2163,11 @@ impl<'a> Formatter<'a> {
// FIXME: Decide what public API we want for these two flags.
// https://github.com/rust-lang/rust/issues/48584
fn debug_lower_hex(&self) -> bool {
self.options.debug_as_hex == Some(DebugAsHex::Lower)
self.options.flags & (1 << rt::Flag::DebugLowerHex as u32) != 0
}
fn debug_upper_hex(&self) -> bool {
self.options.debug_as_hex == Some(DebugAsHex::Upper)
self.options.flags & (1 << rt::Flag::DebugUpperHex as u32) != 0
}
/// Creates a [`DebugStruct`] builder designed to assist with creation of

16
library/core/tests/fmt/mod.rs
View file

@ -58,21 +58,17 @@ fn formatting_options_flags() {
for alternate in [true, false] {
for sign_aware_zero_pad in [true, false] {
for debug_as_hex in [None, Some(DebugAsHex::Lower), Some(DebugAsHex::Upper)] {
let mut original_formatting_options = FormattingOptions::new();
original_formatting_options
let mut formatting_options = FormattingOptions::new();
formatting_options
.sign(sign)
.sign_aware_zero_pad(sign_aware_zero_pad)
.alternate(alternate)
.debug_as_hex(debug_as_hex);
let mut formatting_options_with_flags_set_to_self = original_formatting_options;
formatting_options_with_flags_set_to_self
.flags(formatting_options_with_flags_set_to_self.get_flags());
assert_eq!(
original_formatting_options, formatting_options_with_flags_set_to_self,
"Reading and setting flags changes FormattingOptions; Sign({sign:?}), Alternate({alternate:?}). DebugAsHex({debug_as_hex:?})"
)
assert_eq!(formatting_options.get_sign(), sign);
assert_eq!(formatting_options.get_alternate(), alternate);
assert_eq!(formatting_options.get_sign_aware_zero_pad(), sign_aware_zero_pad);
assert_eq!(formatting_options.get_debug_as_hex(), debug_as_hex);
}
}
}