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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
commit | 698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch) | |
tree | 173a775858bd501c378080a10dca74132f05bc50 /compiler/rustc_expand/src/proc_macro_server.rs | |
parent | Initial commit. (diff) | |
download | rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip |
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | compiler/rustc_expand/src/proc_macro_server.rs | 766 |
1 files changed, 766 insertions, 0 deletions
diff --git a/compiler/rustc_expand/src/proc_macro_server.rs b/compiler/rustc_expand/src/proc_macro_server.rs new file mode 100644 index 000000000..7d9a4aed0 --- /dev/null +++ b/compiler/rustc_expand/src/proc_macro_server.rs @@ -0,0 +1,766 @@ +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) = cursor.next() { + let (Token { kind, span }, joint) = 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, spacing) => (token, spacing == Joint), + }; + + 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_alone(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::TokenStream::delimited( + tokenstream::DelimSpan { open, close }, + delimiter.to_internal(), + stream.unwrap_or_default(), + ); + } + TokenTree::Ident(self::Ident { sym, is_raw, span }) => { + rustc.sess().symbol_gallery.insert(sym, span); + return tokenstream::TokenStream::token_alone(Ident(sym, is_raw), span); + } + 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_alone(minus, span); + let b = tokenstream::TokenTree::token_alone(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_alone(minus, span); + let b = tokenstream::TokenTree::token_alone(float, span); + return [a, b].into_iter().collect(); + } + TokenTree::Literal(self::Literal { kind, symbol, suffix, span }) => { + return tokenstream::TokenStream::token_alone( + TokenKind::lit(kind.to_internal(), symbol, suffix), + span, + ); + } + }; + + 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!(), + }; + + if joint { + tokenstream::TokenStream::token_joint(kind, span) + } else { + tokenstream::TokenStream::token_alone(kind, span) + } + } +} + +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::TokenStream::token_alone(token::Ident(l.token.symbol, false), l.span), + ), + ast::ExprKind::Lit(l) => { + Ok(tokenstream::TokenStream::token_alone(token::Literal(l.token), l.span)) + } + 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_alone(token::BinOp(token::Minus), e.span), + tokenstream::TokenTree::token_alone(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()) + } +} |