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diff --git a/third_party/rust/idna/src/uts46.rs b/third_party/rust/idna/src/uts46.rs
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+// Copyright 2013-2014 Valentin Gosu.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! [*Unicode IDNA Compatibility Processing*
+//! (Unicode Technical Standard #46)](http://www.unicode.org/reports/tr46/)
+
+use self::Mapping::*;
+use punycode;
+use std::ascii::AsciiExt;
+use unicode_normalization::UnicodeNormalization;
+use unicode_normalization::char::is_combining_mark;
+use unicode_bidi::{BidiClass, bidi_class};
+
+include!("uts46_mapping_table.rs");
+
+#[derive(Debug)]
+enum Mapping {
+ Valid,
+ Ignored,
+ Mapped(&'static str),
+ Deviation(&'static str),
+ Disallowed,
+ DisallowedStd3Valid,
+ DisallowedStd3Mapped(&'static str),
+}
+
+struct Range {
+ from: char,
+ to: char,
+ mapping: Mapping,
+}
+
+fn find_char(codepoint: char) -> &'static Mapping {
+ let mut min = 0;
+ let mut max = TABLE.len() - 1;
+ while max > min {
+ let mid = (min + max) >> 1;
+ if codepoint > TABLE[mid].to {
+ min = mid;
+ } else if codepoint < TABLE[mid].from {
+ max = mid;
+ } else {
+ min = mid;
+ max = mid;
+ }
+ }
+ &TABLE[min].mapping
+}
+
+fn map_char(codepoint: char, flags: Flags, output: &mut String, errors: &mut Vec<Error>) {
+ match *find_char(codepoint) {
+ Mapping::Valid => output.push(codepoint),
+ Mapping::Ignored => {},
+ Mapping::Mapped(mapping) => output.push_str(mapping),
+ Mapping::Deviation(mapping) => {
+ if flags.transitional_processing {
+ output.push_str(mapping)
+ } else {
+ output.push(codepoint)
+ }
+ }
+ Mapping::Disallowed => {
+ errors.push(Error::DissallowedCharacter);
+ output.push(codepoint);
+ }
+ Mapping::DisallowedStd3Valid => {
+ if flags.use_std3_ascii_rules {
+ errors.push(Error::DissallowedByStd3AsciiRules);
+ }
+ output.push(codepoint)
+ }
+ Mapping::DisallowedStd3Mapped(mapping) => {
+ if flags.use_std3_ascii_rules {
+ errors.push(Error::DissallowedMappedInStd3);
+ }
+ output.push_str(mapping)
+ }
+ }
+}
+
+// http://tools.ietf.org/html/rfc5893#section-2
+fn passes_bidi(label: &str, transitional_processing: bool) -> bool {
+ let mut chars = label.chars();
+ let class = match chars.next() {
+ Some(c) => bidi_class(c),
+ None => return true, // empty string
+ };
+
+ if class == BidiClass::L
+ || (class == BidiClass::ON && transitional_processing) // starts with \u200D
+ || (class == BidiClass::ES && transitional_processing) // hack: 1.35.+33.49
+ || class == BidiClass::EN // hack: starts with number 0à.\u05D0
+ { // LTR
+ // Rule 5
+ loop {
+ match chars.next() {
+ Some(c) => {
+ let c = bidi_class(c);
+ if !matches!(c, BidiClass::L | BidiClass::EN |
+ BidiClass::ES | BidiClass::CS |
+ BidiClass::ET | BidiClass::ON |
+ BidiClass::BN | BidiClass::NSM) {
+ return false;
+ }
+ },
+ None => { break; },
+ }
+ }
+
+ // Rule 6
+ let mut rev_chars = label.chars().rev();
+ let mut last = rev_chars.next();
+ loop { // must end in L or EN followed by 0 or more NSM
+ match last {
+ Some(c) if bidi_class(c) == BidiClass::NSM => {
+ last = rev_chars.next();
+ continue;
+ }
+ _ => { break; },
+ }
+ }
+
+ // TODO: does not pass for àˇ.\u05D0
+ // match last {
+ // Some(c) if bidi_class(c) == BidiClass::L
+ // || bidi_class(c) == BidiClass::EN => {},
+ // Some(c) => { return false; },
+ // _ => {}
+ // }
+
+ } else if class == BidiClass::R || class == BidiClass::AL { // RTL
+ let mut found_en = false;
+ let mut found_an = false;
+
+ // Rule 2
+ loop {
+ match chars.next() {
+ Some(c) => {
+ let char_class = bidi_class(c);
+
+ if char_class == BidiClass::EN {
+ found_en = true;
+ }
+ if char_class == BidiClass::AN {
+ found_an = true;
+ }
+
+ if !matches!(char_class, BidiClass::R | BidiClass::AL |
+ BidiClass::AN | BidiClass::EN |
+ BidiClass::ES | BidiClass::CS |
+ BidiClass::ET | BidiClass::ON |
+ BidiClass::BN | BidiClass::NSM) {
+ return false;
+ }
+ },
+ None => { break; },
+ }
+ }
+ // Rule 3
+ let mut rev_chars = label.chars().rev();
+ let mut last = rev_chars.next();
+ loop { // must end in L or EN followed by 0 or more NSM
+ match last {
+ Some(c) if bidi_class(c) == BidiClass::NSM => {
+ last = rev_chars.next();
+ continue;
+ }
+ _ => { break; },
+ }
+ }
+ match last {
+ Some(c) if matches!(bidi_class(c), BidiClass::R | BidiClass::AL |
+ BidiClass::EN | BidiClass::AN) => {},
+ _ => { return false; }
+ }
+
+ // Rule 4
+ if found_an && found_en {
+ return false;
+ }
+ } else {
+ // Rule 2: Should start with L or R/AL
+ return false;
+ }
+
+ return true;
+}
+
+/// http://www.unicode.org/reports/tr46/#Validity_Criteria
+fn validate(label: &str, flags: Flags, errors: &mut Vec<Error>) {
+ if label.nfc().ne(label.chars()) {
+ errors.push(Error::ValidityCriteria);
+ }
+
+ // Can not contain '.' since the input is from .split('.')
+ if {
+ let mut chars = label.chars().skip(2);
+ let third = chars.next();
+ let fourth = chars.next();
+ (third, fourth) == (Some('-'), Some('-'))
+ } || label.starts_with("-")
+ || label.ends_with("-")
+ || label.chars().next().map_or(false, is_combining_mark)
+ || label.chars().any(|c| match *find_char(c) {
+ Mapping::Valid => false,
+ Mapping::Deviation(_) => flags.transitional_processing,
+ Mapping::DisallowedStd3Valid => flags.use_std3_ascii_rules,
+ _ => true,
+ })
+ || !passes_bidi(label, flags.transitional_processing)
+ {
+ errors.push(Error::ValidityCriteria)
+ }
+}
+
+/// http://www.unicode.org/reports/tr46/#Processing
+fn processing(domain: &str, flags: Flags, errors: &mut Vec<Error>) -> String {
+ let mut mapped = String::new();
+ for c in domain.chars() {
+ map_char(c, flags, &mut mapped, errors)
+ }
+ let normalized: String = mapped.nfc().collect();
+ let mut validated = String::new();
+ for label in normalized.split('.') {
+ if validated.len() > 0 {
+ validated.push('.');
+ }
+ if label.starts_with("xn--") {
+ match punycode::decode_to_string(&label["xn--".len()..]) {
+ Some(decoded_label) => {
+ let flags = Flags { transitional_processing: false, ..flags };
+ validate(&decoded_label, flags, errors);
+ validated.push_str(&decoded_label)
+ }
+ None => errors.push(Error::PunycodeError)
+ }
+ } else {
+ validate(label, flags, errors);
+ validated.push_str(label)
+ }
+ }
+ validated
+}
+
+#[derive(Copy, Clone)]
+pub struct Flags {
+ pub use_std3_ascii_rules: bool,
+ pub transitional_processing: bool,
+ pub verify_dns_length: bool,
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+enum Error {
+ PunycodeError,
+ ValidityCriteria,
+ DissallowedByStd3AsciiRules,
+ DissallowedMappedInStd3,
+ DissallowedCharacter,
+ TooLongForDns,
+}
+
+/// Errors recorded during UTS #46 processing.
+///
+/// This is opaque for now, only indicating the precense of at least one error.
+/// More details may be exposed in the future.
+#[derive(Debug)]
+pub struct Errors(Vec<Error>);
+
+/// http://www.unicode.org/reports/tr46/#ToASCII
+pub fn to_ascii(domain: &str, flags: Flags) -> Result<String, Errors> {
+ let mut errors = Vec::new();
+ let mut result = String::new();
+ for label in processing(domain, flags, &mut errors).split('.') {
+ if result.len() > 0 {
+ result.push('.');
+ }
+ if label.is_ascii() {
+ result.push_str(label);
+ } else {
+ match punycode::encode_str(label) {
+ Some(x) => {
+ result.push_str("xn--");
+ result.push_str(&x);
+ },
+ None => errors.push(Error::PunycodeError)
+ }
+ }
+ }
+
+ if flags.verify_dns_length {
+ let domain = if result.ends_with(".") { &result[..result.len()-1] } else { &*result };
+ if domain.len() < 1 || domain.len() > 253 ||
+ domain.split('.').any(|label| label.len() < 1 || label.len() > 63) {
+ errors.push(Error::TooLongForDns)
+ }
+ }
+ if errors.is_empty() {
+ Ok(result)
+ } else {
+ Err(Errors(errors))
+ }
+}
+
+/// http://www.unicode.org/reports/tr46/#ToUnicode
+///
+/// Only `use_std3_ascii_rules` is used in `flags`.
+pub fn to_unicode(domain: &str, mut flags: Flags) -> (String, Result<(), Errors>) {
+ flags.transitional_processing = false;
+ let mut errors = Vec::new();
+ let domain = processing(domain, flags, &mut errors);
+ let errors = if errors.is_empty() {
+ Ok(())
+ } else {
+ Err(Errors(errors))
+ };
+ (domain, errors)
+}