#[cfg(feature = "parsing")]
use buffer::Cursor;
#[cfg(feature = "parsing")]
use synom::PResult;
#[cfg(feature = "parsing")]
use token::{Brace, Bracket, Paren};
#[cfg(feature = "parsing")]
use {parse_error, MacroDelimiter};
#[cfg(feature = "extra-traits")]
use std::hash::{Hash, Hasher};
#[cfg(any(feature = "parsing", feature = "extra-traits"))]
use proc_macro2::{Delimiter, TokenNode, TokenStream, TokenTree};
#[cfg(feature = "parsing")]
pub fn delimited(input: Cursor) -> PResult<(MacroDelimiter, TokenStream)> {
match input.token_tree() {
Some((
TokenTree {
span,
kind: TokenNode::Group(delimiter, tts),
},
rest,
)) => {
let delimiter = match delimiter {
Delimiter::Parenthesis => MacroDelimiter::Paren(Paren(span)),
Delimiter::Brace => MacroDelimiter::Brace(Brace(span)),
Delimiter::Bracket => MacroDelimiter::Bracket(Bracket(span)),
Delimiter::None => return parse_error(),
};
Ok(((delimiter, tts), rest))
}
_ => parse_error(),
}
}
#[cfg(all(feature = "full", feature = "parsing"))]
pub fn braced(input: Cursor) -> PResult<(Brace, TokenStream)> {
match input.token_tree() {
Some((
TokenTree {
span,
kind: TokenNode::Group(Delimiter::Brace, tts),
},
rest,
)) => Ok(((Brace(span), tts), rest)),
_ => parse_error(),
}
}
#[cfg(all(feature = "full", feature = "parsing"))]
pub fn parenthesized(input: Cursor) -> PResult<(Paren, TokenStream)> {
match input.token_tree() {
Some((
TokenTree {
span,
kind: TokenNode::Group(Delimiter::Parenthesis, tts),
},
rest,
)) => Ok(((Paren(span), tts), rest)),
_ => parse_error(),
}
}
#[cfg(feature = "extra-traits")]
pub struct TokenTreeHelper<'a>(pub &'a TokenTree);
#[cfg(feature = "extra-traits")]
impl<'a> PartialEq for TokenTreeHelper<'a> {
fn eq(&self, other: &Self) -> bool {
use proc_macro2::Spacing;
match (&self.0.kind, &other.0.kind) {
(&TokenNode::Group(d1, ref s1), &TokenNode::Group(d2, ref s2)) => {
match (d1, d2) {
(Delimiter::Parenthesis, Delimiter::Parenthesis)
| (Delimiter::Brace, Delimiter::Brace)
| (Delimiter::Bracket, Delimiter::Bracket)
| (Delimiter::None, Delimiter::None) => {}
_ => return false,
}
let s1 = s1.clone().into_iter();
let mut s2 = s2.clone().into_iter();
for item1 in s1 {
let item2 = match s2.next() {
Some(item) => item,
None => return false,
};
if TokenTreeHelper(&item1) != TokenTreeHelper(&item2) {
return false;
}
}
s2.next().is_none()
}
(&TokenNode::Op(o1, k1), &TokenNode::Op(o2, k2)) => {
o1 == o2 && match (k1, k2) {
(Spacing::Alone, Spacing::Alone) | (Spacing::Joint, Spacing::Joint) => true,
_ => false,
}
}
(&TokenNode::Literal(ref l1), &TokenNode::Literal(ref l2)) => {
l1.to_string() == l2.to_string()
}
(&TokenNode::Term(ref s1), &TokenNode::Term(ref s2)) => s1.as_str() == s2.as_str(),
_ => false,
}
}
}
#[cfg(feature = "extra-traits")]
impl<'a> Hash for TokenTreeHelper<'a> {
fn hash<H: Hasher>(&self, h: &mut H) {
use proc_macro2::Spacing;
match self.0.kind {
TokenNode::Group(delim, ref stream) => {
0u8.hash(h);
match delim {
Delimiter::Parenthesis => 0u8.hash(h),
Delimiter::Brace => 1u8.hash(h),
Delimiter::Bracket => 2u8.hash(h),
Delimiter::None => 3u8.hash(h),
}
for item in stream.clone() {
TokenTreeHelper(&item).hash(h);
}
0xffu8.hash(h); }
TokenNode::Op(op, kind) => {
1u8.hash(h);
op.hash(h);
match kind {
Spacing::Alone => 0u8.hash(h),
Spacing::Joint => 1u8.hash(h),
}
}
TokenNode::Literal(ref lit) => (2u8, lit.to_string()).hash(h),
TokenNode::Term(ref word) => (3u8, word.as_str()).hash(h),
}
}
}
#[cfg(feature = "extra-traits")]
pub struct TokenStreamHelper<'a>(pub &'a TokenStream);
#[cfg(feature = "extra-traits")]
impl<'a> PartialEq for TokenStreamHelper<'a> {
fn eq(&self, other: &Self) -> bool {
let left = self.0.clone().into_iter().collect::<Vec<_>>();
let right = other.0.clone().into_iter().collect::<Vec<_>>();
if left.len() != right.len() {
return false;
}
for (a, b) in left.into_iter().zip(right) {
if TokenTreeHelper(&a) != TokenTreeHelper(&b) {
return false;
}
}
true
}
}
#[cfg(feature = "extra-traits")]
impl<'a> Hash for TokenStreamHelper<'a> {
fn hash<H: Hasher>(&self, state: &mut H) {
let tts = self.0.clone().into_iter().collect::<Vec<_>>();
tts.len().hash(state);
for tt in tts {
TokenTreeHelper(&tt).hash(state);
}
}
}