rust/compiler/rustc_expand/src/proc_macro_server.rs
Nika Layzell c4acac6443 proc_macro: Move subspan to be a method on Span in the bridge
This method is still only used for Literal::subspan, however the
implementation only depends on the Span component, so it is simpler and
more efficient for now to pass down only the information that is needed.
In the future, if more information about the Literal is required in the
implementation (e.g. to validate that spans line up as expected with
source text), that extra information can be added back with extra
arguments.
2022-07-18 13:06:51 -04:00

768 lines
27 KiB
Rust

use crate::base::ExtCtxt;
use rustc_ast as ast;
use rustc_ast::token;
use rustc_ast::tokenstream::{self, Spacing::*, TokenStream};
use rustc_ast_pretty::pprust;
use rustc_data_structures::fx::FxHashMap;
use rustc_data_structures::sync::Lrc;
use rustc_errors::{Diagnostic, MultiSpan, PResult};
use rustc_parse::lexer::nfc_normalize;
use rustc_parse::parse_stream_from_source_str;
use rustc_session::parse::ParseSess;
use rustc_span::def_id::CrateNum;
use rustc_span::symbol::{self, sym, Symbol};
use rustc_span::{BytePos, FileName, Pos, SourceFile, Span};
use pm::bridge::{
server, DelimSpan, ExpnGlobals, Group, Ident, LitKind, Literal, Punct, TokenTree,
};
use pm::{Delimiter, Level, LineColumn};
use std::ops::Bound;
trait FromInternal<T> {
fn from_internal(x: T) -> Self;
}
trait ToInternal<T> {
fn to_internal(self) -> T;
}
impl FromInternal<token::Delimiter> for Delimiter {
fn from_internal(delim: token::Delimiter) -> Delimiter {
match delim {
token::Delimiter::Parenthesis => Delimiter::Parenthesis,
token::Delimiter::Brace => Delimiter::Brace,
token::Delimiter::Bracket => Delimiter::Bracket,
token::Delimiter::Invisible => Delimiter::None,
}
}
}
impl ToInternal<token::Delimiter> for Delimiter {
fn to_internal(self) -> token::Delimiter {
match self {
Delimiter::Parenthesis => token::Delimiter::Parenthesis,
Delimiter::Brace => token::Delimiter::Brace,
Delimiter::Bracket => token::Delimiter::Bracket,
Delimiter::None => token::Delimiter::Invisible,
}
}
}
impl FromInternal<token::LitKind> for LitKind {
fn from_internal(kind: token::LitKind) -> Self {
match kind {
token::Byte => LitKind::Byte,
token::Char => LitKind::Char,
token::Integer => LitKind::Integer,
token::Float => LitKind::Float,
token::Str => LitKind::Str,
token::StrRaw(n) => LitKind::StrRaw(n),
token::ByteStr => LitKind::ByteStr,
token::ByteStrRaw(n) => LitKind::ByteStrRaw(n),
token::Err => LitKind::Err,
token::Bool => unreachable!(),
}
}
}
impl ToInternal<token::LitKind> for LitKind {
fn to_internal(self) -> token::LitKind {
match self {
LitKind::Byte => token::Byte,
LitKind::Char => token::Char,
LitKind::Integer => token::Integer,
LitKind::Float => token::Float,
LitKind::Str => token::Str,
LitKind::StrRaw(n) => token::StrRaw(n),
LitKind::ByteStr => token::ByteStr,
LitKind::ByteStrRaw(n) => token::ByteStrRaw(n),
LitKind::Err => token::Err,
}
}
}
impl FromInternal<(TokenStream, &mut Rustc<'_, '_>)> for Vec<TokenTree<TokenStream, Span, Symbol>> {
fn from_internal((stream, rustc): (TokenStream, &mut Rustc<'_, '_>)) -> Self {
use rustc_ast::token::*;
// Estimate the capacity as `stream.len()` rounded up to the next power
// of two to limit the number of required reallocations.
let mut trees = Vec::with_capacity(stream.len().next_power_of_two());
let mut cursor = stream.into_trees();
while let Some((tree, spacing)) = cursor.next_with_spacing() {
let joint = spacing == Joint;
let Token { kind, span } = match tree {
tokenstream::TokenTree::Delimited(span, delim, tts) => {
let delimiter = pm::Delimiter::from_internal(delim);
trees.push(TokenTree::Group(Group {
delimiter,
stream: Some(tts),
span: DelimSpan {
open: span.open,
close: span.close,
entire: span.entire(),
},
}));
continue;
}
tokenstream::TokenTree::Token(token) => token,
};
let mut op = |s: &str| {
assert!(s.is_ascii());
trees.extend(s.as_bytes().iter().enumerate().map(|(idx, &ch)| {
TokenTree::Punct(Punct { ch, joint: joint || idx != s.len() - 1, span })
}));
};
match kind {
Eq => op("="),
Lt => op("<"),
Le => op("<="),
EqEq => op("=="),
Ne => op("!="),
Ge => op(">="),
Gt => op(">"),
AndAnd => op("&&"),
OrOr => op("||"),
Not => op("!"),
Tilde => op("~"),
BinOp(Plus) => op("+"),
BinOp(Minus) => op("-"),
BinOp(Star) => op("*"),
BinOp(Slash) => op("/"),
BinOp(Percent) => op("%"),
BinOp(Caret) => op("^"),
BinOp(And) => op("&"),
BinOp(Or) => op("|"),
BinOp(Shl) => op("<<"),
BinOp(Shr) => op(">>"),
BinOpEq(Plus) => op("+="),
BinOpEq(Minus) => op("-="),
BinOpEq(Star) => op("*="),
BinOpEq(Slash) => op("/="),
BinOpEq(Percent) => op("%="),
BinOpEq(Caret) => op("^="),
BinOpEq(And) => op("&="),
BinOpEq(Or) => op("|="),
BinOpEq(Shl) => op("<<="),
BinOpEq(Shr) => op(">>="),
At => op("@"),
Dot => op("."),
DotDot => op(".."),
DotDotDot => op("..."),
DotDotEq => op("..="),
Comma => op(","),
Semi => op(";"),
Colon => op(":"),
ModSep => op("::"),
RArrow => op("->"),
LArrow => op("<-"),
FatArrow => op("=>"),
Pound => op("#"),
Dollar => op("$"),
Question => op("?"),
SingleQuote => op("'"),
Ident(sym, is_raw) => trees.push(TokenTree::Ident(Ident { sym, is_raw, span })),
Lifetime(name) => {
let ident = symbol::Ident::new(name, span).without_first_quote();
trees.extend([
TokenTree::Punct(Punct { ch: b'\'', joint: true, span }),
TokenTree::Ident(Ident { sym: ident.name, is_raw: false, span }),
]);
}
Literal(token::Lit { kind, symbol, suffix }) => {
trees.push(TokenTree::Literal(self::Literal {
kind: FromInternal::from_internal(kind),
symbol,
suffix,
span,
}));
}
DocComment(_, attr_style, data) => {
let mut escaped = String::new();
for ch in data.as_str().chars() {
escaped.extend(ch.escape_debug());
}
let stream = [
Ident(sym::doc, false),
Eq,
TokenKind::lit(token::Str, Symbol::intern(&escaped), None),
]
.into_iter()
.map(|kind| tokenstream::TokenTree::token(kind, span))
.collect();
trees.push(TokenTree::Punct(Punct { ch: b'#', joint: false, span }));
if attr_style == ast::AttrStyle::Inner {
trees.push(TokenTree::Punct(Punct { ch: b'!', joint: false, span }));
}
trees.push(TokenTree::Group(Group {
delimiter: pm::Delimiter::Bracket,
stream: Some(stream),
span: DelimSpan::from_single(span),
}));
}
Interpolated(nt) if let NtIdent(ident, is_raw) = *nt => {
trees.push(TokenTree::Ident(Ident { sym: ident.name, is_raw, span: ident.span }))
}
Interpolated(nt) => {
let stream = TokenStream::from_nonterminal_ast(&nt);
// A hack used to pass AST fragments to attribute and derive
// macros as a single nonterminal token instead of a token
// stream. Such token needs to be "unwrapped" and not
// represented as a delimited group.
// FIXME: It needs to be removed, but there are some
// compatibility issues (see #73345).
if crate::base::nt_pretty_printing_compatibility_hack(&nt, rustc.sess()) {
trees.extend(Self::from_internal((stream, rustc)));
} else {
trees.push(TokenTree::Group(Group {
delimiter: pm::Delimiter::None,
stream: Some(stream),
span: DelimSpan::from_single(span),
}))
}
}
OpenDelim(..) | CloseDelim(..) => unreachable!(),
Eof => unreachable!(),
}
}
trees
}
}
impl ToInternal<TokenStream> for (TokenTree<TokenStream, Span, Symbol>, &mut Rustc<'_, '_>) {
fn to_internal(self) -> TokenStream {
use rustc_ast::token::*;
let (tree, rustc) = self;
let (ch, joint, span) = match tree {
TokenTree::Punct(Punct { ch, joint, span }) => (ch, joint, span),
TokenTree::Group(Group { delimiter, stream, span: DelimSpan { open, close, .. } }) => {
return tokenstream::TokenTree::Delimited(
tokenstream::DelimSpan { open, close },
delimiter.to_internal(),
stream.unwrap_or_default(),
)
.into();
}
TokenTree::Ident(self::Ident { sym, is_raw, span }) => {
rustc.sess().symbol_gallery.insert(sym, span);
return tokenstream::TokenTree::token(Ident(sym, is_raw), span).into();
}
TokenTree::Literal(self::Literal {
kind: self::LitKind::Integer,
symbol,
suffix,
span,
}) if symbol.as_str().starts_with('-') => {
let minus = BinOp(BinOpToken::Minus);
let symbol = Symbol::intern(&symbol.as_str()[1..]);
let integer = TokenKind::lit(token::Integer, symbol, suffix);
let a = tokenstream::TokenTree::token(minus, span);
let b = tokenstream::TokenTree::token(integer, span);
return [a, b].into_iter().collect();
}
TokenTree::Literal(self::Literal {
kind: self::LitKind::Float,
symbol,
suffix,
span,
}) if symbol.as_str().starts_with('-') => {
let minus = BinOp(BinOpToken::Minus);
let symbol = Symbol::intern(&symbol.as_str()[1..]);
let float = TokenKind::lit(token::Float, symbol, suffix);
let a = tokenstream::TokenTree::token(minus, span);
let b = tokenstream::TokenTree::token(float, span);
return [a, b].into_iter().collect();
}
TokenTree::Literal(self::Literal { kind, symbol, suffix, span }) => {
return tokenstream::TokenTree::token(
TokenKind::lit(kind.to_internal(), symbol, suffix),
span,
)
.into();
}
};
let kind = match ch {
b'=' => Eq,
b'<' => Lt,
b'>' => Gt,
b'!' => Not,
b'~' => Tilde,
b'+' => BinOp(Plus),
b'-' => BinOp(Minus),
b'*' => BinOp(Star),
b'/' => BinOp(Slash),
b'%' => BinOp(Percent),
b'^' => BinOp(Caret),
b'&' => BinOp(And),
b'|' => BinOp(Or),
b'@' => At,
b'.' => Dot,
b',' => Comma,
b';' => Semi,
b':' => Colon,
b'#' => Pound,
b'$' => Dollar,
b'?' => Question,
b'\'' => SingleQuote,
_ => unreachable!(),
};
let tree = tokenstream::TokenTree::token(kind, span);
TokenStream::new(vec![(tree, if joint { Joint } else { Alone })])
}
}
impl ToInternal<rustc_errors::Level> for Level {
fn to_internal(self) -> rustc_errors::Level {
match self {
Level::Error => rustc_errors::Level::Error { lint: false },
Level::Warning => rustc_errors::Level::Warning(None),
Level::Note => rustc_errors::Level::Note,
Level::Help => rustc_errors::Level::Help,
_ => unreachable!("unknown proc_macro::Level variant: {:?}", self),
}
}
}
pub struct FreeFunctions;
pub(crate) struct Rustc<'a, 'b> {
ecx: &'a mut ExtCtxt<'b>,
def_site: Span,
call_site: Span,
mixed_site: Span,
krate: CrateNum,
rebased_spans: FxHashMap<usize, Span>,
}
impl<'a, 'b> Rustc<'a, 'b> {
pub fn new(ecx: &'a mut ExtCtxt<'b>) -> Self {
let expn_data = ecx.current_expansion.id.expn_data();
Rustc {
def_site: ecx.with_def_site_ctxt(expn_data.def_site),
call_site: ecx.with_call_site_ctxt(expn_data.call_site),
mixed_site: ecx.with_mixed_site_ctxt(expn_data.call_site),
krate: expn_data.macro_def_id.unwrap().krate,
rebased_spans: FxHashMap::default(),
ecx,
}
}
fn sess(&self) -> &ParseSess {
self.ecx.parse_sess()
}
}
impl server::Types for Rustc<'_, '_> {
type FreeFunctions = FreeFunctions;
type TokenStream = TokenStream;
type SourceFile = Lrc<SourceFile>;
type MultiSpan = Vec<Span>;
type Diagnostic = Diagnostic;
type Span = Span;
type Symbol = Symbol;
}
impl server::FreeFunctions for Rustc<'_, '_> {
fn track_env_var(&mut self, var: &str, value: Option<&str>) {
self.sess()
.env_depinfo
.borrow_mut()
.insert((Symbol::intern(var), value.map(Symbol::intern)));
}
fn track_path(&mut self, path: &str) {
self.sess().file_depinfo.borrow_mut().insert(Symbol::intern(path));
}
fn literal_from_str(&mut self, s: &str) -> Result<Literal<Self::Span, Self::Symbol>, ()> {
let name = FileName::proc_macro_source_code(s);
let mut parser = rustc_parse::new_parser_from_source_str(self.sess(), name, s.to_owned());
let first_span = parser.token.span.data();
let minus_present = parser.eat(&token::BinOp(token::Minus));
let lit_span = parser.token.span.data();
let token::Literal(mut lit) = parser.token.kind else {
return Err(());
};
// Check no comment or whitespace surrounding the (possibly negative)
// literal, or more tokens after it.
if (lit_span.hi.0 - first_span.lo.0) as usize != s.len() {
return Err(());
}
if minus_present {
// If minus is present, check no comment or whitespace in between it
// and the literal token.
if first_span.hi.0 != lit_span.lo.0 {
return Err(());
}
// Check literal is a kind we allow to be negated in a proc macro token.
match lit.kind {
token::LitKind::Bool
| token::LitKind::Byte
| token::LitKind::Char
| token::LitKind::Str
| token::LitKind::StrRaw(_)
| token::LitKind::ByteStr
| token::LitKind::ByteStrRaw(_)
| token::LitKind::Err => return Err(()),
token::LitKind::Integer | token::LitKind::Float => {}
}
// Synthesize a new symbol that includes the minus sign.
let symbol = Symbol::intern(&s[..1 + lit.symbol.as_str().len()]);
lit = token::Lit::new(lit.kind, symbol, lit.suffix);
}
let token::Lit { kind, symbol, suffix } = lit;
Ok(Literal {
kind: FromInternal::from_internal(kind),
symbol,
suffix,
span: self.call_site,
})
}
}
impl server::TokenStream for Rustc<'_, '_> {
fn is_empty(&mut self, stream: &Self::TokenStream) -> bool {
stream.is_empty()
}
fn from_str(&mut self, src: &str) -> Self::TokenStream {
parse_stream_from_source_str(
FileName::proc_macro_source_code(src),
src.to_string(),
self.sess(),
Some(self.call_site),
)
}
fn to_string(&mut self, stream: &Self::TokenStream) -> String {
pprust::tts_to_string(stream)
}
fn expand_expr(&mut self, stream: &Self::TokenStream) -> Result<Self::TokenStream, ()> {
// Parse the expression from our tokenstream.
let expr: PResult<'_, _> = try {
let mut p = rustc_parse::stream_to_parser(
self.sess(),
stream.clone(),
Some("proc_macro expand expr"),
);
let expr = p.parse_expr()?;
if p.token != token::Eof {
p.unexpected()?;
}
expr
};
let expr = expr.map_err(|mut err| {
err.emit();
})?;
// Perform eager expansion on the expression.
let expr = self
.ecx
.expander()
.fully_expand_fragment(crate::expand::AstFragment::Expr(expr))
.make_expr();
// NOTE: For now, limit `expand_expr` to exclusively expand to literals.
// This may be relaxed in the future.
// We don't use `TokenStream::from_ast` as the tokenstream currently cannot
// be recovered in the general case.
match &expr.kind {
ast::ExprKind::Lit(l) if l.token.kind == token::Bool => {
Ok(tokenstream::TokenTree::token(token::Ident(l.token.symbol, false), l.span)
.into())
}
ast::ExprKind::Lit(l) => {
Ok(tokenstream::TokenTree::token(token::Literal(l.token), l.span).into())
}
ast::ExprKind::Unary(ast::UnOp::Neg, e) => match &e.kind {
ast::ExprKind::Lit(l) => match l.token {
token::Lit { kind: token::Integer | token::Float, .. } => {
Ok(Self::TokenStream::from_iter([
// FIXME: The span of the `-` token is lost when
// parsing, so we cannot faithfully recover it here.
tokenstream::TokenTree::token(token::BinOp(token::Minus), e.span),
tokenstream::TokenTree::token(token::Literal(l.token), l.span),
]))
}
_ => Err(()),
},
_ => Err(()),
},
_ => Err(()),
}
}
fn from_token_tree(
&mut self,
tree: TokenTree<Self::TokenStream, Self::Span, Self::Symbol>,
) -> Self::TokenStream {
(tree, &mut *self).to_internal()
}
fn concat_trees(
&mut self,
base: Option<Self::TokenStream>,
trees: Vec<TokenTree<Self::TokenStream, Self::Span, Self::Symbol>>,
) -> Self::TokenStream {
let mut builder = tokenstream::TokenStreamBuilder::new();
if let Some(base) = base {
builder.push(base);
}
for tree in trees {
builder.push((tree, &mut *self).to_internal());
}
builder.build()
}
fn concat_streams(
&mut self,
base: Option<Self::TokenStream>,
streams: Vec<Self::TokenStream>,
) -> Self::TokenStream {
let mut builder = tokenstream::TokenStreamBuilder::new();
if let Some(base) = base {
builder.push(base);
}
for stream in streams {
builder.push(stream);
}
builder.build()
}
fn into_trees(
&mut self,
stream: Self::TokenStream,
) -> Vec<TokenTree<Self::TokenStream, Self::Span, Self::Symbol>> {
FromInternal::from_internal((stream, self))
}
}
impl server::SourceFile for Rustc<'_, '_> {
fn eq(&mut self, file1: &Self::SourceFile, file2: &Self::SourceFile) -> bool {
Lrc::ptr_eq(file1, file2)
}
fn path(&mut self, file: &Self::SourceFile) -> String {
match file.name {
FileName::Real(ref name) => name
.local_path()
.expect("attempting to get a file path in an imported file in `proc_macro::SourceFile::path`")
.to_str()
.expect("non-UTF8 file path in `proc_macro::SourceFile::path`")
.to_string(),
_ => file.name.prefer_local().to_string(),
}
}
fn is_real(&mut self, file: &Self::SourceFile) -> bool {
file.is_real_file()
}
}
impl server::MultiSpan for Rustc<'_, '_> {
fn new(&mut self) -> Self::MultiSpan {
vec![]
}
fn push(&mut self, spans: &mut Self::MultiSpan, span: Self::Span) {
spans.push(span)
}
}
impl server::Diagnostic for Rustc<'_, '_> {
fn new(&mut self, level: Level, msg: &str, spans: Self::MultiSpan) -> Self::Diagnostic {
let mut diag = Diagnostic::new(level.to_internal(), msg);
diag.set_span(MultiSpan::from_spans(spans));
diag
}
fn sub(
&mut self,
diag: &mut Self::Diagnostic,
level: Level,
msg: &str,
spans: Self::MultiSpan,
) {
diag.sub(level.to_internal(), msg, MultiSpan::from_spans(spans), None);
}
fn emit(&mut self, mut diag: Self::Diagnostic) {
self.sess().span_diagnostic.emit_diagnostic(&mut diag);
}
}
impl server::Span for Rustc<'_, '_> {
fn debug(&mut self, span: Self::Span) -> String {
if self.ecx.ecfg.span_debug {
format!("{:?}", span)
} else {
format!("{:?} bytes({}..{})", span.ctxt(), span.lo().0, span.hi().0)
}
}
fn source_file(&mut self, span: Self::Span) -> Self::SourceFile {
self.sess().source_map().lookup_char_pos(span.lo()).file
}
fn parent(&mut self, span: Self::Span) -> Option<Self::Span> {
span.parent_callsite()
}
fn source(&mut self, span: Self::Span) -> Self::Span {
span.source_callsite()
}
fn start(&mut self, span: Self::Span) -> LineColumn {
let loc = self.sess().source_map().lookup_char_pos(span.lo());
LineColumn { line: loc.line, column: loc.col.to_usize() }
}
fn end(&mut self, span: Self::Span) -> LineColumn {
let loc = self.sess().source_map().lookup_char_pos(span.hi());
LineColumn { line: loc.line, column: loc.col.to_usize() }
}
fn before(&mut self, span: Self::Span) -> Self::Span {
span.shrink_to_lo()
}
fn after(&mut self, span: Self::Span) -> Self::Span {
span.shrink_to_hi()
}
fn join(&mut self, first: Self::Span, second: Self::Span) -> Option<Self::Span> {
let self_loc = self.sess().source_map().lookup_char_pos(first.lo());
let other_loc = self.sess().source_map().lookup_char_pos(second.lo());
if self_loc.file.name != other_loc.file.name {
return None;
}
Some(first.to(second))
}
fn subspan(
&mut self,
span: Self::Span,
start: Bound<usize>,
end: Bound<usize>,
) -> Option<Self::Span> {
let length = span.hi().to_usize() - span.lo().to_usize();
let start = match start {
Bound::Included(lo) => lo,
Bound::Excluded(lo) => lo.checked_add(1)?,
Bound::Unbounded => 0,
};
let end = match end {
Bound::Included(hi) => hi.checked_add(1)?,
Bound::Excluded(hi) => hi,
Bound::Unbounded => length,
};
// Bounds check the values, preventing addition overflow and OOB spans.
if start > u32::MAX as usize
|| end > u32::MAX as usize
|| (u32::MAX - start as u32) < span.lo().to_u32()
|| (u32::MAX - end as u32) < span.lo().to_u32()
|| start >= end
|| end > length
{
return None;
}
let new_lo = span.lo() + BytePos::from_usize(start);
let new_hi = span.lo() + BytePos::from_usize(end);
Some(span.with_lo(new_lo).with_hi(new_hi))
}
fn resolved_at(&mut self, span: Self::Span, at: Self::Span) -> Self::Span {
span.with_ctxt(at.ctxt())
}
fn source_text(&mut self, span: Self::Span) -> Option<String> {
self.sess().source_map().span_to_snippet(span).ok()
}
/// Saves the provided span into the metadata of
/// *the crate we are currently compiling*, which must
/// be a proc-macro crate. This id can be passed to
/// `recover_proc_macro_span` when our current crate
/// is *run* as a proc-macro.
///
/// Let's suppose that we have two crates - `my_client`
/// and `my_proc_macro`. The `my_proc_macro` crate
/// contains a procedural macro `my_macro`, which
/// is implemented as: `quote! { "hello" }`
///
/// When we *compile* `my_proc_macro`, we will execute
/// the `quote` proc-macro. This will save the span of
/// "hello" into the metadata of `my_proc_macro`. As a result,
/// the body of `my_proc_macro` (after expansion) will end
/// up containing a call that looks like this:
/// `proc_macro::Ident::new("hello", proc_macro::Span::recover_proc_macro_span(0))`
///
/// where `0` is the id returned by this function.
/// When `my_proc_macro` *executes* (during the compilation of `my_client`),
/// the call to `recover_proc_macro_span` will load the corresponding
/// span from the metadata of `my_proc_macro` (which we have access to,
/// since we've loaded `my_proc_macro` from disk in order to execute it).
/// In this way, we have obtained a span pointing into `my_proc_macro`
fn save_span(&mut self, span: Self::Span) -> usize {
self.sess().save_proc_macro_span(span)
}
fn recover_proc_macro_span(&mut self, id: usize) -> Self::Span {
let (resolver, krate, def_site) = (&*self.ecx.resolver, self.krate, self.def_site);
*self.rebased_spans.entry(id).or_insert_with(|| {
// FIXME: `SyntaxContext` for spans from proc macro crates is lost during encoding,
// replace it with a def-site context until we are encoding it properly.
resolver.get_proc_macro_quoted_span(krate, id).with_ctxt(def_site.ctxt())
})
}
}
impl server::Symbol for Rustc<'_, '_> {
fn normalize_and_validate_ident(&mut self, string: &str) -> Result<Self::Symbol, ()> {
let sym = nfc_normalize(string);
if rustc_lexer::is_ident(sym.as_str()) { Ok(sym) } else { Err(()) }
}
}
impl server::Server for Rustc<'_, '_> {
fn globals(&mut self) -> ExpnGlobals<Self::Span> {
ExpnGlobals {
def_site: self.def_site,
call_site: self.call_site,
mixed_site: self.mixed_site,
}
}
fn intern_symbol(string: &str) -> Self::Symbol {
Symbol::intern(string)
}
fn with_symbol_string(symbol: &Self::Symbol, f: impl FnOnce(&str)) {
f(&symbol.as_str())
}
}