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This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

use std::error;
use std::fmt;
use std::result;
use crate::hir;
/// A type alias for errors specific to Unicode handling of classes.
pub type Result<T> = result::Result<T, Error>;
/// An inclusive range of codepoints from a generated file (hence the static
/// lifetime).
type Range = &'static [(char, char)];
/// An error that occurs when dealing with Unicode.
///
/// We don't impl the Error trait here because these always get converted
/// into other public errors. (This error type isn't exported.)
#[derive(Debug)]
pub enum Error {
PropertyNotFound,
PropertyValueNotFound,
// Not used when unicode-perl is enabled.
#[allow(dead_code)]
PerlClassNotFound,
}
/// A type alias for errors specific to Unicode case folding.
pub type FoldResult<T> = result::Result<T, CaseFoldError>;
/// An error that occurs when Unicode-aware simple case folding fails.
///
/// This error can occur when the case mapping tables necessary for Unicode
/// aware case folding are unavailable. This only occurs when the
/// `unicode-case` feature is disabled. (The feature is enabled by default.)
#[derive(Debug)]
pub struct CaseFoldError(());
impl error::Error for CaseFoldError {}
impl fmt::Display for CaseFoldError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(
f,
"Unicode-aware case folding is not available \
(probably because the unicode-case feature is not enabled)"
)
}
}
/// An error that occurs when the Unicode-aware `\w` class is unavailable.
///
/// This error can occur when the data tables necessary for the Unicode aware
/// Perl character class `\w` are unavailable. This only occurs when the
/// `unicode-perl` feature is disabled. (The feature is enabled by default.)
#[derive(Debug)]
pub struct UnicodeWordError(());
impl error::Error for UnicodeWordError {}
impl fmt::Display for UnicodeWordError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(
f,
"Unicode-aware \\w class is not available \
(probably because the unicode-perl feature is not enabled)"
)
}
}
/// Return an iterator over the equivalence class of simple case mappings
/// for the given codepoint. The equivalence class does not include the
/// given codepoint.
///
/// If the equivalence class is empty, then this returns the next scalar
/// value that has a non-empty equivalence class, if it exists. If no such
/// scalar value exists, then `None` is returned. The point of this behavior
/// is to permit callers to avoid calling `simple_fold` more than they need
/// to, since there is some cost to fetching the equivalence class.
///
/// This returns an error if the Unicode case folding tables are not available.
pub fn simple_fold(
c: char,
) -> FoldResult<result::Result<impl Iterator<Item = char>, Option<char>>> {
#[cfg(not(feature = "unicode-case"))]
fn imp(
_: char,
) -> FoldResult<result::Result<impl Iterator<Item = char>, Option<char>>>
{
use std::option::IntoIter;
Err::<result::Result<IntoIter<char>, _>, _>(CaseFoldError(()))
}
#[cfg(feature = "unicode-case")]
fn imp(
c: char,
) -> FoldResult<result::Result<impl Iterator<Item = char>, Option<char>>>
{
use crate::unicode_tables::case_folding_simple::CASE_FOLDING_SIMPLE;
Ok(CASE_FOLDING_SIMPLE
.binary_search_by_key(&c, |&(c1, _)| c1)
.map(|i| CASE_FOLDING_SIMPLE[i].1.iter().copied())
.map_err(|i| {
if i >= CASE_FOLDING_SIMPLE.len() {
None
} else {
Some(CASE_FOLDING_SIMPLE[i].0)
}
}))
}
imp(c)
}
/// Returns true if and only if the given (inclusive) range contains at least
/// one Unicode scalar value that has a non-empty non-trivial simple case
/// mapping.
///
/// This function panics if `end < start`.
///
/// This returns an error if the Unicode case folding tables are not available.
pub fn contains_simple_case_mapping(
start: char,
end: char,
) -> FoldResult<bool> {
#[cfg(not(feature = "unicode-case"))]
fn imp(_: char, _: char) -> FoldResult<bool> {
Err(CaseFoldError(()))
}
#[cfg(feature = "unicode-case")]
fn imp(start: char, end: char) -> FoldResult<bool> {
use crate::unicode_tables::case_folding_simple::CASE_FOLDING_SIMPLE;
use std::cmp::Ordering;
assert!(start <= end);
Ok(CASE_FOLDING_SIMPLE
.binary_search_by(|&(c, _)| {
if start <= c && c <= end {
Ordering::Equal
} else if c > end {
Ordering::Greater
} else {
Ordering::Less
}
})
.is_ok())
}
imp(start, end)
}
/// A query for finding a character class defined by Unicode. This supports
/// either use of a property name directly, or lookup by property value. The
/// former generally refers to Binary properties (see UTS#44, Table 8), but
/// as a special exception (see UTS#18, Section 1.2) both general categories
/// (an enumeration) and scripts (a catalog) are supported as if each of their
/// possible values were a binary property.
///
/// In all circumstances, property names and values are normalized and
/// canonicalized. That is, `GC == gc == GeneralCategory == general_category`.
///
/// The lifetime `'a` refers to the shorter of the lifetimes of property name
/// and property value.
#[derive(Debug)]
pub enum ClassQuery<'a> {
/// Return a class corresponding to a Unicode binary property, named by
/// a single letter.
OneLetter(char),
/// Return a class corresponding to a Unicode binary property.
///
/// Note that, by special exception (see UTS#18, Section 1.2), both
/// general category values and script values are permitted here as if
/// they were a binary property.
Binary(&'a str),
/// Return a class corresponding to all codepoints whose property
/// (identified by `property_name`) corresponds to the given value
/// (identified by `property_value`).
ByValue {
/// A property name.
property_name: &'a str,
/// A property value.
property_value: &'a str,
},
}
impl<'a> ClassQuery<'a> {
fn canonicalize(&self) -> Result<CanonicalClassQuery> {
match *self {
ClassQuery::OneLetter(c) => self.canonical_binary(&c.to_string()),
ClassQuery::Binary(name) => self.canonical_binary(name),
ClassQuery::ByValue { property_name, property_value } => {
let property_name = symbolic_name_normalize(property_name);
let property_value = symbolic_name_normalize(property_value);
let canon_name = match canonical_prop(&property_name)? {
None => return Err(Error::PropertyNotFound),
Some(canon_name) => canon_name,
};
Ok(match canon_name {
"General_Category" => {
let canon = match canonical_gencat(&property_value)? {
None => return Err(Error::PropertyValueNotFound),
Some(canon) => canon,
};
CanonicalClassQuery::GeneralCategory(canon)
}
"Script" => {
let canon = match canonical_script(&property_value)? {
None => return Err(Error::PropertyValueNotFound),
Some(canon) => canon,
};
CanonicalClassQuery::Script(canon)
}
_ => {
let vals = match property_values(canon_name)? {
None => return Err(Error::PropertyValueNotFound),
Some(vals) => vals,
};
let canon_val =
match canonical_value(vals, &property_value) {
None => {
return Err(Error::PropertyValueNotFound)
}
Some(canon_val) => canon_val,
};
CanonicalClassQuery::ByValue {
property_name: canon_name,
property_value: canon_val,
}
}
})
}
}
}
fn canonical_binary(&self, name: &str) -> Result<CanonicalClassQuery> {
let norm = symbolic_name_normalize(name);
// This is a special case where 'cf' refers to the 'Format' general
// category, but where the 'cf' abbreviation is also an abbreviation
// for the 'Case_Folding' property. But we want to treat it as
// a general category. (Currently, we don't even support the
// 'Case_Folding' property. But if we do in the future, users will be
// required to spell it out.)
if norm != "cf" {
if let Some(canon) = canonical_prop(&norm)? {
return Ok(CanonicalClassQuery::Binary(canon));
}
}
if let Some(canon) = canonical_gencat(&norm)? {
return Ok(CanonicalClassQuery::GeneralCategory(canon));
}
if let Some(canon) = canonical_script(&norm)? {
return Ok(CanonicalClassQuery::Script(canon));
}
Err(Error::PropertyNotFound)
}
}
/// Like ClassQuery, but its parameters have been canonicalized. This also
/// differentiates binary properties from flattened general categories and
/// scripts.
#[derive(Debug, Eq, PartialEq)]
enum CanonicalClassQuery {
/// The canonical binary property name.
Binary(&'static str),
/// The canonical general category name.
GeneralCategory(&'static str),
/// The canonical script name.
Script(&'static str),
/// An arbitrary association between property and value, both of which
/// have been canonicalized.
///
/// Note that by construction, the property name of ByValue will never
/// be General_Category or Script. Those two cases are subsumed by the
/// eponymous variants.
ByValue {
/// The canonical property name.
property_name: &'static str,
/// The canonical property value.
property_value: &'static str,
},
}
/// Looks up a Unicode class given a query. If one doesn't exist, then
/// `None` is returned.
pub fn class(query: ClassQuery<'_>) -> Result<hir::ClassUnicode> {
use self::CanonicalClassQuery::*;
match query.canonicalize()? {
Binary(name) => bool_property(name),
GeneralCategory(name) => gencat(name),
Script(name) => script(name),
ByValue { property_name: "Age", property_value } => {
let mut class = hir::ClassUnicode::empty();
for set in ages(property_value)? {
class.union(&hir_class(set));
}
Ok(class)
}
ByValue { property_name: "Script_Extensions", property_value } => {
script_extension(property_value)
}
ByValue {
property_name: "Grapheme_Cluster_Break",
property_value,
} => gcb(property_value),
ByValue { property_name: "Sentence_Break", property_value } => {
sb(property_value)
}
ByValue { property_name: "Word_Break", property_value } => {
wb(property_value)
}
_ => {
// What else should we support?
Err(Error::PropertyNotFound)
}
}
}
/// Returns a Unicode aware class for \w.
///
/// This returns an error if the data is not available for \w.
pub fn perl_word() -> Result<hir::ClassUnicode> {
#[cfg(not(feature = "unicode-perl"))]
fn imp() -> Result<hir::ClassUnicode> {
Err(Error::PerlClassNotFound)
}
#[cfg(feature = "unicode-perl")]
fn imp() -> Result<hir::ClassUnicode> {
use crate::unicode_tables::perl_word::PERL_WORD;
Ok(hir_class(PERL_WORD))
}
imp()
}
/// Returns a Unicode aware class for \s.
///
/// This returns an error if the data is not available for \s.
pub fn perl_space() -> Result<hir::ClassUnicode> {
#[cfg(not(any(feature = "unicode-perl", feature = "unicode-bool")))]
fn imp() -> Result<hir::ClassUnicode> {
Err(Error::PerlClassNotFound)
}
#[cfg(all(feature = "unicode-perl", not(feature = "unicode-bool")))]
fn imp() -> Result<hir::ClassUnicode> {
use crate::unicode_tables::perl_space::WHITE_SPACE;
Ok(hir_class(WHITE_SPACE))
}
#[cfg(feature = "unicode-bool")]
fn imp() -> Result<hir::ClassUnicode> {
use crate::unicode_tables::property_bool::WHITE_SPACE;
Ok(hir_class(WHITE_SPACE))
}
imp()
}
/// Returns a Unicode aware class for \d.
///
/// This returns an error if the data is not available for \d.
pub fn perl_digit() -> Result<hir::ClassUnicode> {
#[cfg(not(any(feature = "unicode-perl", feature = "unicode-gencat")))]
fn imp() -> Result<hir::ClassUnicode> {
Err(Error::PerlClassNotFound)
}
#[cfg(all(feature = "unicode-perl", not(feature = "unicode-gencat")))]
fn imp() -> Result<hir::ClassUnicode> {
use crate::unicode_tables::perl_decimal::DECIMAL_NUMBER;
Ok(hir_class(DECIMAL_NUMBER))
}
#[cfg(feature = "unicode-gencat")]
fn imp() -> Result<hir::ClassUnicode> {
use crate::unicode_tables::general_category::DECIMAL_NUMBER;
Ok(hir_class(DECIMAL_NUMBER))
}
imp()
}
/// Build a Unicode HIR class from a sequence of Unicode scalar value ranges.
pub fn hir_class(ranges: &[(char, char)]) -> hir::ClassUnicode {
let hir_ranges: Vec<hir::ClassUnicodeRange> = ranges
.iter()
.map(|&(s, e)| hir::ClassUnicodeRange::new(s, e))
.collect();
hir::ClassUnicode::new(hir_ranges)
}
/// Returns true only if the given codepoint is in the `\w` character class.
///
/// If the `unicode-perl` feature is not enabled, then this returns an error.
pub fn is_word_character(c: char) -> result::Result<bool, UnicodeWordError> {
#[cfg(not(feature = "unicode-perl"))]
fn imp(_: char) -> result::Result<bool, UnicodeWordError> {
Err(UnicodeWordError(()))
}
#[cfg(feature = "unicode-perl")]
fn imp(c: char) -> result::Result<bool, UnicodeWordError> {
use crate::is_word_byte;
use crate::unicode_tables::perl_word::PERL_WORD;
use std::cmp::Ordering;
if c <= 0x7F as char && is_word_byte(c as u8) {
return Ok(true);
}
Ok(PERL_WORD
.binary_search_by(|&(start, end)| {
if start <= c && c <= end {
Ordering::Equal
} else if start > c {
Ordering::Greater
} else {
Ordering::Less
}
})
.is_ok())
}
imp(c)
}
/// A mapping of property values for a specific property.
///
/// The first element of each tuple is a normalized property value while the
/// second element of each tuple is the corresponding canonical property
/// value.
type PropertyValues = &'static [(&'static str, &'static str)];
fn canonical_gencat(normalized_value: &str) -> Result<Option<&'static str>> {
Ok(match normalized_value {
"any" => Some("Any"),
"assigned" => Some("Assigned"),
"ascii" => Some("ASCII"),
_ => {
let gencats = property_values("General_Category")?.unwrap();
canonical_value(gencats, normalized_value)
}
})
}
fn canonical_script(normalized_value: &str) -> Result<Option<&'static str>> {
let scripts = property_values("Script")?.unwrap();
Ok(canonical_value(scripts, normalized_value))
}
/// Find the canonical property name for the given normalized property name.
///
/// If no such property exists, then `None` is returned.
///
/// The normalized property name must have been normalized according to
/// UAX44 LM3, which can be done using `symbolic_name_normalize`.
///
/// If the property names data is not available, then an error is returned.
fn canonical_prop(normalized_name: &str) -> Result<Option<&'static str>> {
#[cfg(not(any(
feature = "unicode-age",
feature = "unicode-bool",
feature = "unicode-gencat",
feature = "unicode-perl",
feature = "unicode-script",
feature = "unicode-segment",
)))]
fn imp(_: &str) -> Result<Option<&'static str>> {
Err(Error::PropertyNotFound)
}
#[cfg(any(
feature = "unicode-age",
feature = "unicode-bool",
feature = "unicode-gencat",
feature = "unicode-perl",
feature = "unicode-script",
feature = "unicode-segment",
))]
fn imp(name: &str) -> Result<Option<&'static str>> {
use crate::unicode_tables::property_names::PROPERTY_NAMES;
Ok(PROPERTY_NAMES
.binary_search_by_key(&name, |&(n, _)| n)
.ok()
.map(|i| PROPERTY_NAMES[i].1))
}
imp(normalized_name)
}
/// Find the canonical property value for the given normalized property
/// value.
///
/// The given property values should correspond to the values for the property
/// under question, which can be found using `property_values`.
///
/// If no such property value exists, then `None` is returned.
///
/// The normalized property value must have been normalized according to
/// UAX44 LM3, which can be done using `symbolic_name_normalize`.
fn canonical_value(
vals: PropertyValues,
normalized_value: &str,
) -> Option<&'static str> {
vals.binary_search_by_key(&normalized_value, |&(n, _)| n)
.ok()
.map(|i| vals[i].1)
}
/// Return the table of property values for the given property name.
///
/// If the property values data is not available, then an error is returned.
fn property_values(
canonical_property_name: &'static str,
) -> Result<Option<PropertyValues>> {
#[cfg(not(any(
feature = "unicode-age",
feature = "unicode-bool",
feature = "unicode-gencat",
feature = "unicode-perl",
feature = "unicode-script",
feature = "unicode-segment",
)))]
fn imp(_: &'static str) -> Result<Option<PropertyValues>> {
Err(Error::PropertyValueNotFound)
}
#[cfg(any(
feature = "unicode-age",
feature = "unicode-bool",
feature = "unicode-gencat",
feature = "unicode-perl",
feature = "unicode-script",
feature = "unicode-segment",
))]
fn imp(name: &'static str) -> Result<Option<PropertyValues>> {
use crate::unicode_tables::property_values::PROPERTY_VALUES;
Ok(PROPERTY_VALUES
.binary_search_by_key(&name, |&(n, _)| n)
.ok()
.map(|i| PROPERTY_VALUES[i].1))
}
imp(canonical_property_name)
}
// This is only used in some cases, but small enough to just let it be dead
// instead of figuring out (and maintaining) the right set of features.
#[allow(dead_code)]
fn property_set(
name_map: &'static [(&'static str, Range)],
canonical: &'static str,
) -> Option<Range> {
name_map
.binary_search_by_key(&canonical, |x| x.0)
.ok()
.map(|i| name_map[i].1)
}
/// Returns an iterator over Unicode Age sets. Each item corresponds to a set
/// of codepoints that were added in a particular revision of Unicode. The
/// iterator yields items in chronological order.
///
/// If the given age value isn't valid or if the data isn't available, then an
/// error is returned instead.
fn ages(canonical_age: &str) -> Result<impl Iterator<Item = Range>> {
#[cfg(not(feature = "unicode-age"))]
fn imp(_: &str) -> Result<impl Iterator<Item = Range>> {
use std::option::IntoIter;
Err::<IntoIter<Range>, _>(Error::PropertyNotFound)
}
#[cfg(feature = "unicode-age")]
fn imp(canonical_age: &str) -> Result<impl Iterator<Item = Range>> {
use crate::unicode_tables::age;
const AGES: &[(&str, Range)] = &[
("V1_1", age::V1_1),
("V2_0", age::V2_0),
("V2_1", age::V2_1),
("V3_0", age::V3_0),
("V3_1", age::V3_1),
("V3_2", age::V3_2),
("V4_0", age::V4_0),
("V4_1", age::V4_1),
("V5_0", age::V5_0),
("V5_1", age::V5_1),
("V5_2", age::V5_2),
("V6_0", age::V6_0),
("V6_1", age::V6_1),
("V6_2", age::V6_2),
("V6_3", age::V6_3),
("V7_0", age::V7_0),
("V8_0", age::V8_0),
("V9_0", age::V9_0),
("V10_0", age::V10_0),
("V11_0", age::V11_0),
("V12_0", age::V12_0),
("V12_1", age::V12_1),
("V13_0", age::V13_0),
("V14_0", age::V14_0),
("V15_0", age::V15_0),
];
assert_eq!(AGES.len(), age::BY_NAME.len(), "ages are out of sync");
let pos = AGES.iter().position(|&(age, _)| canonical_age == age);
match pos {
None => Err(Error::PropertyValueNotFound),
Some(i) => Ok(AGES[..=i].iter().map(|&(_, classes)| classes)),
}
}
imp(canonical_age)
}
/// Returns the Unicode HIR class corresponding to the given general category.
///
/// Name canonicalization is assumed to be performed by the caller.
///
/// If the given general category could not be found, or if the general
/// category data is not available, then an error is returned.
fn gencat(canonical_name: &'static str) -> Result<hir::ClassUnicode> {
#[cfg(not(feature = "unicode-gencat"))]
fn imp(_: &'static str) -> Result<hir::ClassUnicode> {
Err(Error::PropertyNotFound)
}
#[cfg(feature = "unicode-gencat")]
fn imp(name: &'static str) -> Result<hir::ClassUnicode> {
use crate::unicode_tables::general_category::BY_NAME;
match name {
"ASCII" => Ok(hir_class(&[('\0', '\x7F')])),
"Any" => Ok(hir_class(&[('\0', '\u{10FFFF}')])),
"Assigned" => {
let mut cls = gencat("Unassigned")?;
cls.negate();
Ok(cls)
}
name => property_set(BY_NAME, name)
.map(hir_class)
.ok_or(Error::PropertyValueNotFound),
}
}
match canonical_name {
"Decimal_Number" => perl_digit(),
name => imp(name),
}
}
/// Returns the Unicode HIR class corresponding to the given script.
///
/// Name canonicalization is assumed to be performed by the caller.
///
/// If the given script could not be found, or if the script data is not
/// available, then an error is returned.
fn script(canonical_name: &'static str) -> Result<hir::ClassUnicode> {
#[cfg(not(feature = "unicode-script"))]
fn imp(_: &'static str) -> Result<hir::ClassUnicode> {
Err(Error::PropertyNotFound)
}
#[cfg(feature = "unicode-script")]
fn imp(name: &'static str) -> Result<hir::ClassUnicode> {
use crate::unicode_tables::script::BY_NAME;
property_set(BY_NAME, name)
.map(hir_class)
.ok_or(Error::PropertyValueNotFound)
}
imp(canonical_name)
}
/// Returns the Unicode HIR class corresponding to the given script extension.
///
/// Name canonicalization is assumed to be performed by the caller.
///
/// If the given script extension could not be found, or if the script data is
/// not available, then an error is returned.
fn script_extension(
canonical_name: &'static str,
) -> Result<hir::ClassUnicode> {
#[cfg(not(feature = "unicode-script"))]
fn imp(_: &'static str) -> Result<hir::ClassUnicode> {
Err(Error::PropertyNotFound)
}
#[cfg(feature = "unicode-script")]
fn imp(name: &'static str) -> Result<hir::ClassUnicode> {
use crate::unicode_tables::script_extension::BY_NAME;
property_set(BY_NAME, name)
.map(hir_class)
.ok_or(Error::PropertyValueNotFound)
}
imp(canonical_name)
}
/// Returns the Unicode HIR class corresponding to the given Unicode boolean
/// property.
///
/// Name canonicalization is assumed to be performed by the caller.
///
/// If the given boolean property could not be found, or if the boolean
/// property data is not available, then an error is returned.
fn bool_property(canonical_name: &'static str) -> Result<hir::ClassUnicode> {
#[cfg(not(feature = "unicode-bool"))]
fn imp(_: &'static str) -> Result<hir::ClassUnicode> {
Err(Error::PropertyNotFound)
}
#[cfg(feature = "unicode-bool")]
fn imp(name: &'static str) -> Result<hir::ClassUnicode> {
use crate::unicode_tables::property_bool::BY_NAME;
property_set(BY_NAME, name)
.map(hir_class)
.ok_or(Error::PropertyNotFound)
}
match canonical_name {
"Decimal_Number" => perl_digit(),
"White_Space" => perl_space(),
name => imp(name),
}
}
/// Returns the Unicode HIR class corresponding to the given grapheme cluster
/// break property.
///
/// Name canonicalization is assumed to be performed by the caller.
///
/// If the given property could not be found, or if the corresponding data is
/// not available, then an error is returned.
fn gcb(canonical_name: &'static str) -> Result<hir::ClassUnicode> {
#[cfg(not(feature = "unicode-segment"))]
fn imp(_: &'static str) -> Result<hir::ClassUnicode> {
Err(Error::PropertyNotFound)
}
#[cfg(feature = "unicode-segment")]
fn imp(name: &'static str) -> Result<hir::ClassUnicode> {
use crate::unicode_tables::grapheme_cluster_break::BY_NAME;
property_set(BY_NAME, name)
.map(hir_class)
.ok_or(Error::PropertyValueNotFound)
}
imp(canonical_name)
}
/// Returns the Unicode HIR class corresponding to the given word break
/// property.
///
/// Name canonicalization is assumed to be performed by the caller.
///
/// If the given property could not be found, or if the corresponding data is
/// not available, then an error is returned.
fn wb(canonical_name: &'static str) -> Result<hir::ClassUnicode> {
#[cfg(not(feature = "unicode-segment"))]
fn imp(_: &'static str) -> Result<hir::ClassUnicode> {
Err(Error::PropertyNotFound)
}
#[cfg(feature = "unicode-segment")]
fn imp(name: &'static str) -> Result<hir::ClassUnicode> {
use crate::unicode_tables::word_break::BY_NAME;
property_set(BY_NAME, name)
.map(hir_class)
.ok_or(Error::PropertyValueNotFound)
}
imp(canonical_name)
}
/// Returns the Unicode HIR class corresponding to the given sentence
/// break property.
///
/// Name canonicalization is assumed to be performed by the caller.
///
/// If the given property could not be found, or if the corresponding data is
/// not available, then an error is returned.
fn sb(canonical_name: &'static str) -> Result<hir::ClassUnicode> {
#[cfg(not(feature = "unicode-segment"))]
fn imp(_: &'static str) -> Result<hir::ClassUnicode> {
Err(Error::PropertyNotFound)
}
#[cfg(feature = "unicode-segment")]
fn imp(name: &'static str) -> Result<hir::ClassUnicode> {
use crate::unicode_tables::sentence_break::BY_NAME;
property_set(BY_NAME, name)
.map(hir_class)
.ok_or(Error::PropertyValueNotFound)
}
imp(canonical_name)
}
/// Like symbolic_name_normalize_bytes, but operates on a string.
fn symbolic_name_normalize(x: &str) -> String {
let mut tmp = x.as_bytes().to_vec();
let len = symbolic_name_normalize_bytes(&mut tmp).len();
tmp.truncate(len);
// This should always succeed because `symbolic_name_normalize_bytes`
// guarantees that `&tmp[..len]` is always valid UTF-8.
//
// N.B. We could avoid the additional UTF-8 check here, but it's unlikely
// to be worth skipping the additional safety check. A benchmark must
// justify it first.
String::from_utf8(tmp).unwrap()
}
/// Normalize the given symbolic name in place according to UAX44-LM3.
///
/// A "symbolic name" typically corresponds to property names and property
/// value aliases. Note, though, that it should not be applied to property
/// string values.
///
/// The slice returned is guaranteed to be valid UTF-8 for all possible values
/// of `slice`.
///
/// See: https://unicode.org/reports/tr44/#UAX44-LM3
fn symbolic_name_normalize_bytes(slice: &mut [u8]) -> &mut [u8] {
// I couldn't find a place in the standard that specified that property
// names/aliases had a particular structure (unlike character names), but
// we assume that it's ASCII only and drop anything that isn't ASCII.
let mut start = 0;
let mut starts_with_is = false;
if slice.len() >= 2 {
// Ignore any "is" prefix.
starts_with_is = slice[0..2] == b"is"[..]
|| slice[0..2] == b"IS"[..]
|| slice[0..2] == b"iS"[..]
|| slice[0..2] == b"Is"[..];
if starts_with_is {
start = 2;
}
}
let mut next_write = 0;
for i in start..slice.len() {
// VALIDITY ARGUMENT: To guarantee that the resulting slice is valid
// UTF-8, we ensure that the slice contains only ASCII bytes. In
// particular, we drop every non-ASCII byte from the normalized string.
let b = slice[i];
if b == b' ' || b == b'_' || b == b'-' {
continue;
} else if b'A' <= b && b <= b'Z' {
slice[next_write] = b + (b'a' - b'A');
next_write += 1;
} else if b <= 0x7F {
slice[next_write] = b;
next_write += 1;
}
}
// Special case: ISO_Comment has a 'isc' abbreviation. Since we generally
// ignore 'is' prefixes, the 'isc' abbreviation gets caught in the cross
// fire and ends up creating an alias for 'c' to 'ISO_Comment', but it
// is actually an alias for the 'Other' general category.
if starts_with_is && next_write == 1 && slice[0] == b'c' {
slice[0] = b'i';
slice[1] = b's';
slice[2] = b'c';
next_write = 3;
}
&mut slice[..next_write]
}
#[cfg(test)]
mod tests {
use super::{
contains_simple_case_mapping, simple_fold, symbolic_name_normalize,
symbolic_name_normalize_bytes,
};
#[cfg(feature = "unicode-case")]
fn simple_fold_ok(c: char) -> impl Iterator<Item = char> {
simple_fold(c).unwrap().unwrap()
}
#[cfg(feature = "unicode-case")]
fn simple_fold_err(c: char) -> Option<char> {
match simple_fold(c).unwrap() {
Ok(_) => unreachable!("simple_fold returned Ok iterator"),
Err(next) => next,
}
}
#[cfg(feature = "unicode-case")]
fn contains_case_map(start: char, end: char) -> bool {
contains_simple_case_mapping(start, end).unwrap()
}
#[test]
#[cfg(feature = "unicode-case")]
fn simple_fold_k() {
let xs: Vec<char> = simple_fold_ok('k').collect();
assert_eq!(xs, vec!['K', '']);
let xs: Vec<char> = simple_fold_ok('K').collect();
assert_eq!(xs, vec!['k', '']);
let xs: Vec<char> = simple_fold_ok('').collect();
assert_eq!(xs, vec!['K', 'k']);
}
#[test]
#[cfg(feature = "unicode-case")]
fn simple_fold_a() {
let xs: Vec<char> = simple_fold_ok('a').collect();
assert_eq!(xs, vec!['A']);
let xs: Vec<char> = simple_fold_ok('A').collect();
assert_eq!(xs, vec!['a']);
}
#[test]
#[cfg(feature = "unicode-case")]
fn simple_fold_empty() {
assert_eq!(Some('A'), simple_fold_err('?'));
assert_eq!(Some('A'), simple_fold_err('@'));
assert_eq!(Some('a'), simple_fold_err('['));
assert_eq!(Some('Ⰰ'), simple_fold_err('☃'));
}
#[test]
#[cfg(feature = "unicode-case")]
fn simple_fold_max() {
assert_eq!(None, simple_fold_err('\u{10FFFE}'));
assert_eq!(None, simple_fold_err('\u{10FFFF}'));
}
#[test]
#[cfg(not(feature = "unicode-case"))]
fn simple_fold_disabled() {
assert!(simple_fold('a').is_err());
}
#[test]
#[cfg(feature = "unicode-case")]
fn range_contains() {
assert!(contains_case_map('A', 'A'));
assert!(contains_case_map('Z', 'Z'));
assert!(contains_case_map('A', 'Z'));
assert!(contains_case_map('@', 'A'));
assert!(contains_case_map('Z', '['));
assert!(contains_case_map('☃', 'Ⰰ'));
assert!(!contains_case_map('[', '['));
assert!(!contains_case_map('[', '`'));
assert!(!contains_case_map('☃', '☃'));
}
#[test]
#[cfg(not(feature = "unicode-case"))]
fn range_contains_disabled() {
assert!(contains_simple_case_mapping('a', 'a').is_err());
}
#[test]
#[cfg(feature = "unicode-gencat")]
fn regression_466() {
use super::{CanonicalClassQuery, ClassQuery};
let q = ClassQuery::OneLetter('C');
assert_eq!(
q.canonicalize().unwrap(),
CanonicalClassQuery::GeneralCategory("Other")
);
}
#[test]
fn sym_normalize() {
let sym_norm = symbolic_name_normalize;
assert_eq!(sym_norm("Line_Break"), "linebreak");
assert_eq!(sym_norm("Line-break"), "linebreak");
assert_eq!(sym_norm("linebreak"), "linebreak");
assert_eq!(sym_norm("BA"), "ba");
assert_eq!(sym_norm("ba"), "ba");
assert_eq!(sym_norm("Greek"), "greek");
assert_eq!(sym_norm("isGreek"), "greek");
assert_eq!(sym_norm("IS_Greek"), "greek");
assert_eq!(sym_norm("isc"), "isc");
assert_eq!(sym_norm("is c"), "isc");
assert_eq!(sym_norm("is_c"), "isc");
}
#[test]
fn valid_utf8_symbolic() {
let mut x = b"abc\xFFxyz".to_vec();
let y = symbolic_name_normalize_bytes(&mut x);
assert_eq!(y, b"abcxyz");
}
}