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rustfmt

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This commit is contained in:
Mark Mansi 2019-05-06 13:42:15 -05:00
parent c3b8ab5199
commit 6d26c5f73c
1 changed files with 50 additions and 50 deletions
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100
src/libsyntax/ext/tt/transcribe.rs
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@ -1,10 +1,10 @@
use crate::ast::Ident;
use crate::ext::base::ExtCtxt;
use crate::ext::expand::Marker;
use crate::ext::tt::macro_parser::{NamedMatch, MatchedSeq, MatchedNonterminal};
use crate::ext::tt::macro_parser::{MatchedNonterminal, MatchedSeq, NamedMatch};
use crate::ext::tt::quoted;
use crate::mut_visit::noop_visit_tt;
use crate::parse::token::{self, Token, NtTT};
use crate::parse::token::{self, NtTT, Token};
use crate::tokenstream::{DelimSpan, TokenStream, TokenTree, TreeAndJoint};
use smallvec::{smallvec, SmallVec};
@ -16,18 +16,10 @@ use std::mem;
use std::ops::Add;
use std::rc::Rc;
// An iterator over the token trees in a delimited token tree (`{ ... }`) or a sequence (`$(...)`).
/// An iterator over the token trees in a delimited token tree (`{ ... }`) or a sequence (`$(...)`).
enum Frame {
Delimited {
forest: Lrc<quoted::Delimited>,
idx: usize,
span: DelimSpan,
},
Sequence {
forest: Lrc<quoted::SequenceRepetition>,
idx: usize,
sep: Option<Token>,
},
Delimited { forest: Lrc<quoted::Delimited>, idx: usize, span: DelimSpan },
Sequence { forest: Lrc<quoted::SequenceRepetition>, idx: usize, sep: Option<Token> },
}
impl Frame {
@ -54,13 +46,13 @@ impl Iterator for Frame {
}
}
/// This can do Macro-By-Example transcription. On the other hand, if
/// `src` contains no `TokenTree::{Sequence, MetaVar, MetaVarDecl}`s, `interp` can
/// (and should) be None.
pub fn transcribe(cx: &ExtCtxt<'_>,
interp: Option<FxHashMap<Ident, Rc<NamedMatch>>>,
src: Vec<quoted::TokenTree>)
-> TokenStream {
/// This can do Macro-By-Example transcription. On the other hand, if `src` contains no
/// `TokenTree::{Sequence, MetaVar, MetaVarDecl}`s, `interp` can (and should) be `None`.
pub fn transcribe(
cx: &ExtCtxt<'_>,
interp: Option<FxHashMap<Ident, Rc<NamedMatch>>>,
src: Vec<quoted::TokenTree>,
) -> TokenStream {
let mut stack: SmallVec<[Frame; 1]> = smallvec![Frame::new(src)];
let interpolations = interp.unwrap_or_else(FxHashMap::default); /* just a convenience */
let mut repeats = Vec::new();
@ -84,7 +76,7 @@ pub fn transcribe(cx: &ExtCtxt<'_>,
};
result.push(TokenTree::Token(prev_span, sep).into());
}
continue
continue;
}
}
@ -96,29 +88,30 @@ pub fn transcribe(cx: &ExtCtxt<'_>,
if result_stack.is_empty() {
return TokenStream::new(result);
}
let tree = TokenTree::Delimited(
span,
forest.delim,
TokenStream::new(result).into(),
);
let tree =
TokenTree::Delimited(span, forest.delim, TokenStream::new(result).into());
result = result_stack.pop().unwrap();
result.push(tree.into());
}
}
continue
continue;
};
match tree {
quoted::TokenTree::Sequence(sp, seq) => {
// FIXME(pcwalton): Bad copy.
match lockstep_iter_size(&quoted::TokenTree::Sequence(sp, seq.clone()),
&interpolations,
&repeats) {
match lockstep_iter_size(
&quoted::TokenTree::Sequence(sp, seq.clone()),
&interpolations,
&repeats,
) {
LockstepIterSize::Unconstrained => {
cx.span_fatal(sp.entire(), /* blame macro writer */
cx.span_fatal(
sp.entire(), /* blame macro writer */
"attempted to repeat an expression \
containing no syntax \
variables matched as repeating at this depth");
variables matched as repeating at this depth",
);
}
LockstepIterSize::Contradiction(ref msg) => {
// FIXME #2887 blame macro invoker instead
@ -153,8 +146,10 @@ pub fn transcribe(cx: &ExtCtxt<'_>,
result.push(token.into());
}
} else {
cx.span_fatal(sp, /* blame the macro writer */
&format!("variable '{}' is still repeating at this depth", ident));
cx.span_fatal(
sp, /* blame the macro writer */
&format!("variable '{}' is still repeating at this depth", ident),
);
}
} else {
let ident =
@ -180,10 +175,11 @@ pub fn transcribe(cx: &ExtCtxt<'_>,
}
}
fn lookup_cur_matched(ident: Ident,
interpolations: &FxHashMap<Ident, Rc<NamedMatch>>,
repeats: &[(usize, usize)])
-> Option<Rc<NamedMatch>> {
fn lookup_cur_matched(
ident: Ident,
interpolations: &FxHashMap<Ident, Rc<NamedMatch>>,
repeats: &[(usize, usize)],
) -> Option<Rc<NamedMatch>> {
interpolations.get(&ident).map(|matched| {
let mut matched = matched.clone();
for &(idx, _) in repeats {
@ -217,9 +213,11 @@ impl Add for LockstepIterSize {
LockstepIterSize::Contradiction(_) => other,
LockstepIterSize::Constraint(r_len, _) if l_len == r_len => self,
LockstepIterSize::Constraint(r_len, r_id) => {
let msg = format!("inconsistent lockstep iteration: \
'{}' has {} items, but '{}' has {}",
l_id, l_len, r_id, r_len);
let msg = format!(
"inconsistent lockstep iteration: \
'{}' has {} items, but '{}' has {}",
l_id, l_len, r_id, r_len
);
LockstepIterSize::Contradiction(msg)
}
},
@ -227,30 +225,32 @@ impl Add for LockstepIterSize {
}
}
fn lockstep_iter_size(tree: &quoted::TokenTree,
interpolations: &FxHashMap<Ident, Rc<NamedMatch>>,
repeats: &[(usize, usize)])
-> LockstepIterSize {
fn lockstep_iter_size(
tree: &quoted::TokenTree,
interpolations: &FxHashMap<Ident, Rc<NamedMatch>>,
repeats: &[(usize, usize)],
) -> LockstepIterSize {
use quoted::TokenTree;
match *tree {
TokenTree::Delimited(_, ref delimed) => {
delimed.tts.iter().fold(LockstepIterSize::Unconstrained, |size, tt| {
size + lockstep_iter_size(tt, interpolations, repeats)
})
},
}
TokenTree::Sequence(_, ref seq) => {
seq.tts.iter().fold(LockstepIterSize::Unconstrained, |size, tt| {
size + lockstep_iter_size(tt, interpolations, repeats)
})
},
TokenTree::MetaVar(_, name) | TokenTree::MetaVarDecl(_, name, _) =>
}
TokenTree::MetaVar(_, name) | TokenTree::MetaVarDecl(_, name, _) => {
match lookup_cur_matched(name, interpolations, repeats) {
Some(matched) => match *matched {
MatchedNonterminal(_) => LockstepIterSize::Unconstrained,
MatchedSeq(ref ads, _) => LockstepIterSize::Constraint(ads.len(), name),
},
_ => LockstepIterSize::Unconstrained
},
_ => LockstepIterSize::Unconstrained,
}
}
TokenTree::Token(..) => LockstepIterSize::Unconstrained,
}
}