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Diffstat (limited to '')
-rw-r--r-- | vendor/pest/src/iterators/pair.rs | 389 |
1 files changed, 389 insertions, 0 deletions
diff --git a/vendor/pest/src/iterators/pair.rs b/vendor/pest/src/iterators/pair.rs new file mode 100644 index 000000000..88844a353 --- /dev/null +++ b/vendor/pest/src/iterators/pair.rs @@ -0,0 +1,389 @@ +// pest. The Elegant Parser +// Copyright (c) 2018 DragoČ™ Tiselice +// +// 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. All files in the project carrying such notice may not be copied, +// modified, or distributed except according to those terms. + +use std::fmt; +use std::hash::{Hash, Hasher}; +use std::ptr; +use std::rc::Rc; +use std::str; + +#[cfg(feature = "pretty-print")] +use serde::ser::SerializeStruct; + +use super::pairs::{self, Pairs}; +use super::queueable_token::QueueableToken; +use super::tokens::{self, Tokens}; +use span::{self, Span}; +use RuleType; + +/// A matching pair of [`Token`]s and everything between them. +/// +/// A matching `Token` pair is formed by a `Token::Start` and a subsequent `Token::End` with the +/// same `Rule`, with the condition that all `Token`s between them can form such pairs as well. +/// This is similar to the [brace matching problem](https://en.wikipedia.org/wiki/Brace_matching) in +/// editors. +/// +/// [`Token`]: ../enum.Token.html +#[derive(Clone)] +pub struct Pair<'i, R> { + /// # Safety + /// + /// All `QueueableToken`s' `input_pos` must be valid character boundary indices into `input`. + queue: Rc<Vec<QueueableToken<R>>>, + input: &'i str, + /// Token index into `queue`. + start: usize, +} + +/// # Safety +/// +/// All `QueueableToken`s' `input_pos` must be valid character boundary indices into `input`. +pub unsafe fn new<R: RuleType>( + queue: Rc<Vec<QueueableToken<R>>>, + input: &str, + start: usize, +) -> Pair<R> { + Pair { + queue, + input, + start, + } +} + +impl<'i, R: RuleType> Pair<'i, R> { + /// Returns the `Rule` of the `Pair`. + /// + /// # Examples + /// + /// ``` + /// # use std::rc::Rc; + /// # use pest; + /// # #[allow(non_camel_case_types)] + /// # #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)] + /// enum Rule { + /// a + /// } + /// + /// let input = ""; + /// let pair = pest::state(input, |state| { + /// // generating Token pair with Rule::a ... + /// # state.rule(Rule::a, |s| Ok(s)) + /// }).unwrap().next().unwrap(); + /// + /// assert_eq!(pair.as_rule(), Rule::a); + /// ``` + #[inline] + pub fn as_rule(&self) -> R { + match self.queue[self.pair()] { + QueueableToken::End { rule, .. } => rule, + _ => unreachable!(), + } + } + + /// Captures a slice from the `&str` defined by the token `Pair`. + /// + /// # Examples + /// + /// ``` + /// # use std::rc::Rc; + /// # use pest; + /// # #[allow(non_camel_case_types)] + /// # #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)] + /// enum Rule { + /// ab + /// } + /// + /// let input = "ab"; + /// let pair = pest::state(input, |state| { + /// // generating Token pair with Rule::ab ... + /// # state.rule(Rule::ab, |s| s.match_string("ab")) + /// }).unwrap().next().unwrap(); + /// + /// assert_eq!(pair.as_str(), "ab"); + /// ``` + #[inline] + pub fn as_str(&self) -> &'i str { + let start = self.pos(self.start); + let end = self.pos(self.pair()); + + // Generated positions always come from Positions and are UTF-8 borders. + &self.input[start..end] + } + + /// Returns the `Span` defined by the `Pair`, consuming it. + /// + /// # Examples + /// + /// ``` + /// # use std::rc::Rc; + /// # use pest; + /// # #[allow(non_camel_case_types)] + /// # #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)] + /// enum Rule { + /// ab + /// } + /// + /// let input = "ab"; + /// let pair = pest::state(input, |state| { + /// // generating Token pair with Rule::ab ... + /// # state.rule(Rule::ab, |s| s.match_string("ab")) + /// }).unwrap().next().unwrap(); + /// + /// assert_eq!(pair.into_span().as_str(), "ab"); + /// ``` + #[inline] + #[deprecated(since = "2.0.0", note = "Please use `as_span` instead")] + pub fn into_span(self) -> Span<'i> { + self.as_span() + } + + /// Returns the `Span` defined by the `Pair`, **without** consuming it. + /// + /// # Examples + /// + /// ``` + /// # use std::rc::Rc; + /// # use pest; + /// # #[allow(non_camel_case_types)] + /// # #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)] + /// enum Rule { + /// ab + /// } + /// + /// let input = "ab"; + /// let pair = pest::state(input, |state| { + /// // generating Token pair with Rule::ab ... + /// # state.rule(Rule::ab, |s| s.match_string("ab")) + /// }).unwrap().next().unwrap(); + /// + /// assert_eq!(pair.as_span().as_str(), "ab"); + /// ``` + #[inline] + pub fn as_span(&self) -> Span<'i> { + let start = self.pos(self.start); + let end = self.pos(self.pair()); + + // Generated positions always come from Positions and are UTF-8 borders. + unsafe { span::Span::new_unchecked(self.input, start, end) } + } + + /// Returns the inner `Pairs` between the `Pair`, consuming it. + /// + /// # Examples + /// + /// ``` + /// # use std::rc::Rc; + /// # use pest; + /// # #[allow(non_camel_case_types)] + /// # #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)] + /// enum Rule { + /// a + /// } + /// + /// let input = ""; + /// let pair = pest::state(input, |state| { + /// // generating Token pair with Rule::a ... + /// # state.rule(Rule::a, |s| Ok(s)) + /// }).unwrap().next().unwrap(); + /// + /// assert!(pair.into_inner().next().is_none()); + /// ``` + #[inline] + pub fn into_inner(self) -> Pairs<'i, R> { + let pair = self.pair(); + + pairs::new(self.queue, self.input, self.start + 1, pair) + } + + /// Returns the `Tokens` for the `Pair`. + /// + /// # Examples + /// + /// ``` + /// # use std::rc::Rc; + /// # use pest; + /// # #[allow(non_camel_case_types)] + /// # #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)] + /// enum Rule { + /// a + /// } + /// + /// let input = ""; + /// let pair = pest::state(input, |state| { + /// // generating Token pair with Rule::a ... + /// # state.rule(Rule::a, |s| Ok(s)) + /// }).unwrap().next().unwrap(); + /// let tokens: Vec<_> = pair.tokens().collect(); + /// + /// assert_eq!(tokens.len(), 2); + /// ``` + #[inline] + pub fn tokens(self) -> Tokens<'i, R> { + let end = self.pair(); + + tokens::new(self.queue, self.input, self.start, end + 1) + } + + /// Generates a string that stores the lexical information of `self` in + /// a pretty-printed JSON format. + #[cfg(feature = "pretty-print")] + pub fn to_json(&self) -> String { + ::serde_json::to_string_pretty(self).expect("Failed to pretty-print Pair to json.") + } + + fn pair(&self) -> usize { + match self.queue[self.start] { + QueueableToken::Start { + end_token_index, .. + } => end_token_index, + _ => unreachable!(), + } + } + + fn pos(&self, index: usize) -> usize { + match self.queue[index] { + QueueableToken::Start { input_pos, .. } | QueueableToken::End { input_pos, .. } => { + input_pos + } + } + } +} + +impl<'i, R: RuleType> Pairs<'i, R> { + /// Create a new `Pairs` iterator containing just the single `Pair`. + pub fn single(pair: Pair<'i, R>) -> Self { + let end = pair.pair(); + pairs::new(pair.queue, pair.input, pair.start, end) + } +} + +impl<'i, R: RuleType> fmt::Debug for Pair<'i, R> { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + f.debug_struct("Pair") + .field("rule", &self.as_rule()) + .field("span", &self.as_span()) + .field("inner", &self.clone().into_inner().collect::<Vec<_>>()) + .finish() + } +} + +impl<'i, R: RuleType> fmt::Display for Pair<'i, R> { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + let rule = self.as_rule(); + let start = self.pos(self.start); + let end = self.pos(self.pair()); + let mut pairs = self.clone().into_inner().peekable(); + + if pairs.peek().is_none() { + write!(f, "{:?}({}, {})", rule, start, end) + } else { + write!( + f, + "{:?}({}, {}, [{}])", + rule, + start, + end, + pairs + .map(|pair| format!("{}", pair)) + .collect::<Vec<_>>() + .join(", ") + ) + } + } +} + +impl<'i, R: PartialEq> PartialEq for Pair<'i, R> { + fn eq(&self, other: &Pair<'i, R>) -> bool { + Rc::ptr_eq(&self.queue, &other.queue) + && ptr::eq(self.input, other.input) + && self.start == other.start + } +} + +impl<'i, R: Eq> Eq for Pair<'i, R> {} + +impl<'i, R: Hash> Hash for Pair<'i, R> { + fn hash<H: Hasher>(&self, state: &mut H) { + (&*self.queue as *const Vec<QueueableToken<R>>).hash(state); + (self.input as *const str).hash(state); + self.start.hash(state); + } +} + +#[cfg(feature = "pretty-print")] +impl<'i, R: RuleType> ::serde::Serialize for Pair<'i, R> { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: ::serde::Serializer, + { + let start = self.pos(self.start); + let end = self.pos(self.pair()); + let rule = format!("{:?}", self.as_rule()); + let inner = self.clone().into_inner(); + + let mut ser = serializer.serialize_struct("Pairs", 3)?; + ser.serialize_field("pos", &(start, end))?; + ser.serialize_field("rule", &rule)?; + + if inner.peek().is_none() { + ser.serialize_field("inner", &self.as_str())?; + } else { + ser.serialize_field("inner", &inner)?; + } + + ser.end() + } +} + +#[cfg(test)] +mod tests { + use macros::tests::*; + use parser::Parser; + + #[test] + #[cfg(feature = "pretty-print")] + fn test_pretty_print() { + let pair = AbcParser::parse(Rule::a, "abcde").unwrap().next().unwrap(); + + let expected = r#"{ + "pos": [ + 0, + 3 + ], + "rule": "a", + "inner": { + "pos": [ + 1, + 2 + ], + "pairs": [ + { + "pos": [ + 1, + 2 + ], + "rule": "b", + "inner": "b" + } + ] + } +}"#; + + assert_eq!(expected, pair.to_json()); + } + + #[test] + fn pair_into_inner() { + let pair = AbcParser::parse(Rule::a, "abcde").unwrap().next().unwrap(); // the tokens a(b()) + + let pairs = pair.into_inner(); // the tokens b() + + assert_eq!(2, pairs.tokens().count()); + } +} |