diff options
Diffstat (limited to 'third_party/rust/unic-langid-impl/src/subtags/variant.rs')
-rw-r--r-- | third_party/rust/unic-langid-impl/src/subtags/variant.rs | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/third_party/rust/unic-langid-impl/src/subtags/variant.rs b/third_party/rust/unic-langid-impl/src/subtags/variant.rs new file mode 100644 index 0000000000..8b29a458ec --- /dev/null +++ b/third_party/rust/unic-langid-impl/src/subtags/variant.rs @@ -0,0 +1,78 @@ +use crate::parser::errors::ParserError; +use std::str::FromStr; +use tinystr::TinyStr8; + +#[derive(Debug, PartialEq, Eq, Clone, Hash, PartialOrd, Ord, Copy)] +pub struct Variant(TinyStr8); + +impl Variant { + pub fn from_bytes(v: &[u8]) -> Result<Self, ParserError> { + let slen = v.len(); + + if slen < 4 || slen > 8 { + return Err(ParserError::InvalidSubtag); + } + + let s = TinyStr8::from_bytes(v).map_err(|_| ParserError::InvalidSubtag)?; + + if (slen >= 5 && !s.is_ascii_alphanumeric()) + || (slen == 4 + && !v[0].is_ascii_digit() + && v[1..].iter().any(|c: &u8| !c.is_ascii_alphanumeric())) + { + return Err(ParserError::InvalidSubtag); + } + + Ok(Self(s.to_ascii_lowercase())) + } + + pub fn as_str(&self) -> &str { + self.0.as_str() + } + + /// # Safety + /// + /// This function accepts any u64 that is exected to be a valid + /// `TinyStr8` and a valid `Variant` subtag. + pub const unsafe fn from_raw_unchecked(v: u64) -> Self { + Self(TinyStr8::from_bytes_unchecked(v.to_le_bytes())) + } +} + +impl From<Variant> for u64 { + fn from(input: Variant) -> Self { + u64::from_le_bytes(*input.0.all_bytes()) + } +} + +impl From<&Variant> for u64 { + fn from(input: &Variant) -> Self { + u64::from_le_bytes(*input.0.all_bytes()) + } +} + +impl FromStr for Variant { + type Err = ParserError; + + fn from_str(source: &str) -> Result<Self, Self::Err> { + Self::from_bytes(source.as_bytes()) + } +} + +impl std::fmt::Display for Variant { + fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result { + f.write_str(&self.0) + } +} + +impl PartialEq<&str> for Variant { + fn eq(&self, other: &&str) -> bool { + self.as_str() == *other + } +} + +impl PartialEq<str> for Variant { + fn eq(&self, other: &str) -> bool { + self.as_str() == other + } +} |