Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 634 insertions, 0 deletions

diff --git a/compiler/rustc_ast/src/attr/mod.rs b/compiler/rustc_ast/src/attr/mod.rs
new file mode 100644
index 000000000..86af7769d
--- /dev/null
+++ b/compiler/rustc_ast/src/attr/mod.rs
@@ -0,0 +1,634 @@
+//! Functions dealing with attributes and meta items.
+
+use crate::ast;
+use crate::ast::{AttrId, AttrItem, AttrKind, AttrStyle, Attribute};
+use crate::ast::{Lit, LitKind};
+use crate::ast::{MacArgs, MacArgsEq, MacDelimiter, MetaItem, MetaItemKind, NestedMetaItem};
+use crate::ast::{Path, PathSegment};
+use crate::ptr::P;
+use crate::token::{self, CommentKind, Delimiter, Token};
+use crate::tokenstream::{AttrAnnotatedTokenStream, AttrAnnotatedTokenTree};
+use crate::tokenstream::{DelimSpan, Spacing, TokenTree};
+use crate::tokenstream::{LazyTokenStream, TokenStream};
+use crate::util::comments;
+
+use rustc_data_structures::thin_vec::ThinVec;
+use rustc_index::bit_set::GrowableBitSet;
+use rustc_span::source_map::BytePos;
+use rustc_span::symbol::{sym, Ident, Symbol};
+use rustc_span::Span;
+
+use std::iter;
+
+pub struct MarkedAttrs(GrowableBitSet<AttrId>);
+
+impl MarkedAttrs {
+    // We have no idea how many attributes there will be, so just
+    // initiate the vectors with 0 bits. We'll grow them as necessary.
+    pub fn new() -> Self {
+        MarkedAttrs(GrowableBitSet::new_empty())
+    }
+
+    pub fn mark(&mut self, attr: &Attribute) {
+        self.0.insert(attr.id);
+    }
+
+    pub fn is_marked(&self, attr: &Attribute) -> bool {
+        self.0.contains(attr.id)
+    }
+}
+
+impl NestedMetaItem {
+    /// Returns the `MetaItem` if `self` is a `NestedMetaItem::MetaItem`.
+    pub fn meta_item(&self) -> Option<&MetaItem> {
+        match *self {
+            NestedMetaItem::MetaItem(ref item) => Some(item),
+            _ => None,
+        }
+    }
+
+    /// Returns the `Lit` if `self` is a `NestedMetaItem::Literal`s.
+    pub fn literal(&self) -> Option<&Lit> {
+        match *self {
+            NestedMetaItem::Literal(ref lit) => Some(lit),
+            _ => None,
+        }
+    }
+
+    /// Returns `true` if this list item is a MetaItem with a name of `name`.
+    pub fn has_name(&self, name: Symbol) -> bool {
+        self.meta_item().map_or(false, |meta_item| meta_item.has_name(name))
+    }
+
+    /// For a single-segment meta item, returns its name; otherwise, returns `None`.
+    pub fn ident(&self) -> Option<Ident> {
+        self.meta_item().and_then(|meta_item| meta_item.ident())
+    }
+    pub fn name_or_empty(&self) -> Symbol {
+        self.ident().unwrap_or_else(Ident::empty).name
+    }
+
+    /// Gets the string value if `self` is a `MetaItem` and the `MetaItem` is a
+    /// `MetaItemKind::NameValue` variant containing a string, otherwise `None`.
+    pub fn value_str(&self) -> Option<Symbol> {
+        self.meta_item().and_then(|meta_item| meta_item.value_str())
+    }
+
+    /// Returns a name and single literal value tuple of the `MetaItem`.
+    pub fn name_value_literal(&self) -> Option<(Symbol, &Lit)> {
+        self.meta_item().and_then(|meta_item| {
+            meta_item.meta_item_list().and_then(|meta_item_list| {
+                if meta_item_list.len() == 1
+                    && let Some(ident) = meta_item.ident()
+                    && let Some(lit) = meta_item_list[0].literal()
+                {
+                    return Some((ident.name, lit));
+                }
+                None
+            })
+        })
+    }
+
+    /// Gets a list of inner meta items from a list `MetaItem` type.
+    pub fn meta_item_list(&self) -> Option<&[NestedMetaItem]> {
+        self.meta_item().and_then(|meta_item| meta_item.meta_item_list())
+    }
+
+    /// Returns `true` if the variant is `MetaItem`.
+    pub fn is_meta_item(&self) -> bool {
+        self.meta_item().is_some()
+    }
+
+    /// Returns `true` if `self` is a `MetaItem` and the meta item is a word.
+    pub fn is_word(&self) -> bool {
+        self.meta_item().map_or(false, |meta_item| meta_item.is_word())
+    }
+
+    /// See [`MetaItem::name_value_literal_span`].
+    pub fn name_value_literal_span(&self) -> Option<Span> {
+        self.meta_item()?.name_value_literal_span()
+    }
+}
+
+impl Attribute {
+    #[inline]
+    pub fn has_name(&self, name: Symbol) -> bool {
+        match self.kind {
+            AttrKind::Normal(ref item, _) => item.path == name,
+            AttrKind::DocComment(..) => false,
+        }
+    }
+
+    /// For a single-segment attribute, returns its name; otherwise, returns `None`.
+    pub fn ident(&self) -> Option<Ident> {
+        match self.kind {
+            AttrKind::Normal(ref item, _) => {
+                if item.path.segments.len() == 1 {
+                    Some(item.path.segments[0].ident)
+                } else {
+                    None
+                }
+            }
+            AttrKind::DocComment(..) => None,
+        }
+    }
+    pub fn name_or_empty(&self) -> Symbol {
+        self.ident().unwrap_or_else(Ident::empty).name
+    }
+
+    pub fn value_str(&self) -> Option<Symbol> {
+        match self.kind {
+            AttrKind::Normal(ref item, _) => item.meta_kind().and_then(|kind| kind.value_str()),
+            AttrKind::DocComment(..) => None,
+        }
+    }
+
+    pub fn meta_item_list(&self) -> Option<Vec<NestedMetaItem>> {
+        match self.kind {
+            AttrKind::Normal(ref item, _) => match item.meta_kind() {
+                Some(MetaItemKind::List(list)) => Some(list),
+                _ => None,
+            },
+            AttrKind::DocComment(..) => None,
+        }
+    }
+
+    pub fn is_word(&self) -> bool {
+        if let AttrKind::Normal(item, _) = &self.kind {
+            matches!(item.args, MacArgs::Empty)
+        } else {
+            false
+        }
+    }
+}
+
+impl MetaItem {
+    /// For a single-segment meta item, returns its name; otherwise, returns `None`.
+    pub fn ident(&self) -> Option<Ident> {
+        if self.path.segments.len() == 1 { Some(self.path.segments[0].ident) } else { None }
+    }
+    pub fn name_or_empty(&self) -> Symbol {
+        self.ident().unwrap_or_else(Ident::empty).name
+    }
+
+    // Example:
+    //     #[attribute(name = "value")]
+    //                 ^^^^^^^^^^^^^^
+    pub fn name_value_literal(&self) -> Option<&Lit> {
+        match &self.kind {
+            MetaItemKind::NameValue(v) => Some(v),
+            _ => None,
+        }
+    }
+
+    pub fn value_str(&self) -> Option<Symbol> {
+        match self.kind {
+            MetaItemKind::NameValue(ref v) => match v.kind {
+                LitKind::Str(ref s, _) => Some(*s),
+                _ => None,
+            },
+            _ => None,
+        }
+    }
+
+    pub fn meta_item_list(&self) -> Option<&[NestedMetaItem]> {
+        match self.kind {
+            MetaItemKind::List(ref l) => Some(&l[..]),
+            _ => None,
+        }
+    }
+
+    pub fn is_word(&self) -> bool {
+        matches!(self.kind, MetaItemKind::Word)
+    }
+
+    pub fn has_name(&self, name: Symbol) -> bool {
+        self.path == name
+    }
+
+    /// This is used in case you want the value span instead of the whole attribute. Example:
+    ///
+    /// ```text
+    /// #[doc(alias = "foo")]
+    /// ```
+    ///
+    /// In here, it'll return a span for `"foo"`.
+    pub fn name_value_literal_span(&self) -> Option<Span> {
+        Some(self.name_value_literal()?.span)
+    }
+}
+
+impl AttrItem {
+    pub fn span(&self) -> Span {
+        self.args.span().map_or(self.path.span, |args_span| self.path.span.to(args_span))
+    }
+
+    pub fn meta(&self, span: Span) -> Option<MetaItem> {
+        Some(MetaItem {
+            path: self.path.clone(),
+            kind: MetaItemKind::from_mac_args(&self.args)?,
+            span,
+        })
+    }
+
+    pub fn meta_kind(&self) -> Option<MetaItemKind> {
+        MetaItemKind::from_mac_args(&self.args)
+    }
+}
+
+impl Attribute {
+    pub fn is_doc_comment(&self) -> bool {
+        match self.kind {
+            AttrKind::Normal(..) => false,
+            AttrKind::DocComment(..) => true,
+        }
+    }
+
+    pub fn doc_str_and_comment_kind(&self) -> Option<(Symbol, CommentKind)> {
+        match self.kind {
+            AttrKind::DocComment(kind, data) => Some((data, kind)),
+            AttrKind::Normal(ref item, _) if item.path == sym::doc => item
+                .meta_kind()
+                .and_then(|kind| kind.value_str())
+                .map(|data| (data, CommentKind::Line)),
+            _ => None,
+        }
+    }
+
+    pub fn doc_str(&self) -> Option<Symbol> {
+        match self.kind {
+            AttrKind::DocComment(.., data) => Some(data),
+            AttrKind::Normal(ref item, _) if item.path == sym::doc => {
+                item.meta_kind().and_then(|kind| kind.value_str())
+            }
+            _ => None,
+        }
+    }
+
+    pub fn may_have_doc_links(&self) -> bool {
+        self.doc_str().map_or(false, |s| comments::may_have_doc_links(s.as_str()))
+    }
+
+    pub fn get_normal_item(&self) -> &AttrItem {
+        match self.kind {
+            AttrKind::Normal(ref item, _) => item,
+            AttrKind::DocComment(..) => panic!("unexpected doc comment"),
+        }
+    }
+
+    pub fn unwrap_normal_item(self) -> AttrItem {
+        match self.kind {
+            AttrKind::Normal(item, _) => item,
+            AttrKind::DocComment(..) => panic!("unexpected doc comment"),
+        }
+    }
+
+    /// Extracts the MetaItem from inside this Attribute.
+    pub fn meta(&self) -> Option<MetaItem> {
+        match self.kind {
+            AttrKind::Normal(ref item, _) => item.meta(self.span),
+            AttrKind::DocComment(..) => None,
+        }
+    }
+
+    pub fn meta_kind(&self) -> Option<MetaItemKind> {
+        match self.kind {
+            AttrKind::Normal(ref item, _) => item.meta_kind(),
+            AttrKind::DocComment(..) => None,
+        }
+    }
+
+    pub fn tokens(&self) -> AttrAnnotatedTokenStream {
+        match self.kind {
+            AttrKind::Normal(_, ref tokens) => tokens
+                .as_ref()
+                .unwrap_or_else(|| panic!("attribute is missing tokens: {:?}", self))
+                .create_token_stream(),
+            AttrKind::DocComment(comment_kind, data) => AttrAnnotatedTokenStream::from((
+                AttrAnnotatedTokenTree::Token(Token::new(
+                    token::DocComment(comment_kind, self.style, data),
+                    self.span,
+                )),
+                Spacing::Alone,
+            )),
+        }
+    }
+}
+
+/* Constructors */
+
+pub fn mk_name_value_item_str(ident: Ident, str: Symbol, str_span: Span) -> MetaItem {
+    let lit_kind = LitKind::Str(str, ast::StrStyle::Cooked);
+    mk_name_value_item(ident, lit_kind, str_span)
+}
+
+pub fn mk_name_value_item(ident: Ident, lit_kind: LitKind, lit_span: Span) -> MetaItem {
+    let lit = Lit::from_lit_kind(lit_kind, lit_span);
+    let span = ident.span.to(lit_span);
+    MetaItem { path: Path::from_ident(ident), span, kind: MetaItemKind::NameValue(lit) }
+}
+
+pub fn mk_list_item(ident: Ident, items: Vec<NestedMetaItem>) -> MetaItem {
+    MetaItem { path: Path::from_ident(ident), span: ident.span, kind: MetaItemKind::List(items) }
+}
+
+pub fn mk_word_item(ident: Ident) -> MetaItem {
+    MetaItem { path: Path::from_ident(ident), span: ident.span, kind: MetaItemKind::Word }
+}
+
+pub fn mk_nested_word_item(ident: Ident) -> NestedMetaItem {
+    NestedMetaItem::MetaItem(mk_word_item(ident))
+}
+
+pub(crate) fn mk_attr_id() -> AttrId {
+    use std::sync::atomic::AtomicU32;
+    use std::sync::atomic::Ordering;
+
+    static NEXT_ATTR_ID: AtomicU32 = AtomicU32::new(0);
+
+    let id = NEXT_ATTR_ID.fetch_add(1, Ordering::SeqCst);
+    assert!(id != u32::MAX);
+    AttrId::from_u32(id)
+}
+
+pub fn mk_attr(style: AttrStyle, path: Path, args: MacArgs, span: Span) -> Attribute {
+    mk_attr_from_item(AttrItem { path, args, tokens: None }, None, style, span)
+}
+
+pub fn mk_attr_from_item(
+    item: AttrItem,
+    tokens: Option<LazyTokenStream>,
+    style: AttrStyle,
+    span: Span,
+) -> Attribute {
+    Attribute { kind: AttrKind::Normal(item, tokens), id: mk_attr_id(), style, span }
+}
+
+/// Returns an inner attribute with the given value and span.
+pub fn mk_attr_inner(item: MetaItem) -> Attribute {
+    mk_attr(AttrStyle::Inner, item.path, item.kind.mac_args(item.span), item.span)
+}
+
+/// Returns an outer attribute with the given value and span.
+pub fn mk_attr_outer(item: MetaItem) -> Attribute {
+    mk_attr(AttrStyle::Outer, item.path, item.kind.mac_args(item.span), item.span)
+}
+
+pub fn mk_doc_comment(
+    comment_kind: CommentKind,
+    style: AttrStyle,
+    data: Symbol,
+    span: Span,
+) -> Attribute {
+    Attribute { kind: AttrKind::DocComment(comment_kind, data), id: mk_attr_id(), style, span }
+}
+
+pub fn list_contains_name(items: &[NestedMetaItem], name: Symbol) -> bool {
+    items.iter().any(|item| item.has_name(name))
+}
+
+impl MetaItem {
+    fn token_trees(&self) -> Vec<TokenTree> {
+        let mut idents = vec![];
+        let mut last_pos = BytePos(0_u32);
+        for (i, segment) in self.path.segments.iter().enumerate() {
+            let is_first = i == 0;
+            if !is_first {
+                let mod_sep_span =
+                    Span::new(last_pos, segment.ident.span.lo(), segment.ident.span.ctxt(), None);
+                idents.push(TokenTree::token_alone(token::ModSep, mod_sep_span));
+            }
+            idents.push(TokenTree::Token(Token::from_ast_ident(segment.ident), Spacing::Alone));
+            last_pos = segment.ident.span.hi();
+        }
+        idents.extend(self.kind.token_trees(self.span));
+        idents
+    }
+
+    fn from_tokens<I>(tokens: &mut iter::Peekable<I>) -> Option<MetaItem>
+    where
+        I: Iterator<Item = TokenTree>,
+    {
+        // FIXME: Share code with `parse_path`.
+        let path = match tokens.next().map(TokenTree::uninterpolate) {
+            Some(TokenTree::Token(
+                Token { kind: kind @ (token::Ident(..) | token::ModSep), span },
+                _,
+            )) => 'arm: {
+                let mut segments = if let token::Ident(name, _) = kind {
+                    if let Some(TokenTree::Token(Token { kind: token::ModSep, .. }, _)) =
+                        tokens.peek()
+                    {
+                        tokens.next();
+                        vec![PathSegment::from_ident(Ident::new(name, span))]
+                    } else {
+                        break 'arm Path::from_ident(Ident::new(name, span));
+                    }
+                } else {
+                    vec![PathSegment::path_root(span)]
+                };
+                loop {
+                    if let Some(TokenTree::Token(Token { kind: token::Ident(name, _), span }, _)) =
+                        tokens.next().map(TokenTree::uninterpolate)
+                    {
+                        segments.push(PathSegment::from_ident(Ident::new(name, span)));
+                    } else {
+                        return None;
+                    }
+                    if let Some(TokenTree::Token(Token { kind: token::ModSep, .. }, _)) =
+                        tokens.peek()
+                    {
+                        tokens.next();
+                    } else {
+                        break;
+                    }
+                }
+                let span = span.with_hi(segments.last().unwrap().ident.span.hi());
+                Path { span, segments, tokens: None }
+            }
+            Some(TokenTree::Token(Token { kind: token::Interpolated(nt), .. }, _)) => match *nt {
+                token::Nonterminal::NtMeta(ref item) => return item.meta(item.path.span),
+                token::Nonterminal::NtPath(ref path) => (**path).clone(),
+                _ => return None,
+            },
+            _ => return None,
+        };
+        let list_closing_paren_pos = tokens.peek().map(|tt| tt.span().hi());
+        let kind = MetaItemKind::from_tokens(tokens)?;
+        let hi = match kind {
+            MetaItemKind::NameValue(ref lit) => lit.span.hi(),
+            MetaItemKind::List(..) => list_closing_paren_pos.unwrap_or(path.span.hi()),
+            _ => path.span.hi(),
+        };
+        let span = path.span.with_hi(hi);
+        Some(MetaItem { path, kind, span })
+    }
+}
+
+impl MetaItemKind {
+    pub fn value_str(&self) -> Option<Symbol> {
+        match self {
+            MetaItemKind::NameValue(ref v) => match v.kind {
+                LitKind::Str(ref s, _) => Some(*s),
+                _ => None,
+            },
+            _ => None,
+        }
+    }
+
+    pub fn mac_args(&self, span: Span) -> MacArgs {
+        match self {
+            MetaItemKind::Word => MacArgs::Empty,
+            MetaItemKind::NameValue(lit) => {
+                let expr = P(ast::Expr {
+                    id: ast::DUMMY_NODE_ID,
+                    kind: ast::ExprKind::Lit(lit.clone()),
+                    span: lit.span,
+                    attrs: ThinVec::new(),
+                    tokens: None,
+                });
+                MacArgs::Eq(span, MacArgsEq::Ast(expr))
+            }
+            MetaItemKind::List(list) => {
+                let mut tts = Vec::new();
+                for (i, item) in list.iter().enumerate() {
+                    if i > 0 {
+                        tts.push(TokenTree::token_alone(token::Comma, span));
+                    }
+                    tts.extend(item.token_trees())
+                }
+                MacArgs::Delimited(
+                    DelimSpan::from_single(span),
+                    MacDelimiter::Parenthesis,
+                    TokenStream::new(tts),
+                )
+            }
+        }
+    }
+
+    fn token_trees(&self, span: Span) -> Vec<TokenTree> {
+        match *self {
+            MetaItemKind::Word => vec![],
+            MetaItemKind::NameValue(ref lit) => {
+                vec![
+                    TokenTree::token_alone(token::Eq, span),
+                    TokenTree::Token(lit.to_token(), Spacing::Alone),
+                ]
+            }
+            MetaItemKind::List(ref list) => {
+                let mut tokens = Vec::new();
+                for (i, item) in list.iter().enumerate() {
+                    if i > 0 {
+                        tokens.push(TokenTree::token_alone(token::Comma, span));
+                    }
+                    tokens.extend(item.token_trees())
+                }
+                vec![TokenTree::Delimited(
+                    DelimSpan::from_single(span),
+                    Delimiter::Parenthesis,
+                    TokenStream::new(tokens),
+                )]
+            }
+        }
+    }
+
+    fn list_from_tokens(tokens: TokenStream) -> Option<MetaItemKind> {
+        let mut tokens = tokens.into_trees().peekable();
+        let mut result = Vec::new();
+        while tokens.peek().is_some() {
+            let item = NestedMetaItem::from_tokens(&mut tokens)?;
+            result.push(item);
+            match tokens.next() {
+                None | Some(TokenTree::Token(Token { kind: token::Comma, .. }, _)) => {}
+                _ => return None,
+            }
+        }
+        Some(MetaItemKind::List(result))
+    }
+
+    fn name_value_from_tokens(
+        tokens: &mut impl Iterator<Item = TokenTree>,
+    ) -> Option<MetaItemKind> {
+        match tokens.next() {
+            Some(TokenTree::Delimited(_, Delimiter::Invisible, inner_tokens)) => {
+                MetaItemKind::name_value_from_tokens(&mut inner_tokens.into_trees())
+            }
+            Some(TokenTree::Token(token, _)) => {
+                Lit::from_token(&token).ok().map(MetaItemKind::NameValue)
+            }
+            _ => None,
+        }
+    }
+
+    fn from_mac_args(args: &MacArgs) -> Option<MetaItemKind> {
+        match args {
+            MacArgs::Empty => Some(MetaItemKind::Word),
+            MacArgs::Delimited(_, MacDelimiter::Parenthesis, tokens) => {
+                MetaItemKind::list_from_tokens(tokens.clone())
+            }
+            MacArgs::Delimited(..) => None,
+            MacArgs::Eq(_, MacArgsEq::Ast(expr)) => match &expr.kind {
+                ast::ExprKind::Lit(lit) => Some(MetaItemKind::NameValue(lit.clone())),
+                _ => None,
+            },
+            MacArgs::Eq(_, MacArgsEq::Hir(lit)) => Some(MetaItemKind::NameValue(lit.clone())),
+        }
+    }
+
+    fn from_tokens(
+        tokens: &mut iter::Peekable<impl Iterator<Item = TokenTree>>,
+    ) -> Option<MetaItemKind> {
+        match tokens.peek() {
+            Some(TokenTree::Delimited(_, Delimiter::Parenthesis, inner_tokens)) => {
+                let inner_tokens = inner_tokens.clone();
+                tokens.next();
+                MetaItemKind::list_from_tokens(inner_tokens)
+            }
+            Some(TokenTree::Delimited(..)) => None,
+            Some(TokenTree::Token(Token { kind: token::Eq, .. }, _)) => {
+                tokens.next();
+                MetaItemKind::name_value_from_tokens(tokens)
+            }
+            _ => Some(MetaItemKind::Word),
+        }
+    }
+}
+
+impl NestedMetaItem {
+    pub fn span(&self) -> Span {
+        match *self {
+            NestedMetaItem::MetaItem(ref item) => item.span,
+            NestedMetaItem::Literal(ref lit) => lit.span,
+        }
+    }
+
+    fn token_trees(&self) -> Vec<TokenTree> {
+        match *self {
+            NestedMetaItem::MetaItem(ref item) => item.token_trees(),
+            NestedMetaItem::Literal(ref lit) => {
+                vec![TokenTree::Token(lit.to_token(), Spacing::Alone)]
+            }
+        }
+    }
+
+    fn from_tokens<I>(tokens: &mut iter::Peekable<I>) -> Option<NestedMetaItem>
+    where
+        I: Iterator<Item = TokenTree>,
+    {
+        match tokens.peek() {
+            Some(TokenTree::Token(token, _))
+                if let Ok(lit) = Lit::from_token(token) =>
+            {
+                tokens.next();
+                return Some(NestedMetaItem::Literal(lit));
+            }
+            Some(TokenTree::Delimited(_, Delimiter::Invisible, inner_tokens)) => {
+                let inner_tokens = inner_tokens.clone();
+                tokens.next();
+                return NestedMetaItem::from_tokens(&mut inner_tokens.into_trees().peekable());
+            }
+            _ => {}
+        }
+        MetaItem::from_tokens(tokens).map(NestedMetaItem::MetaItem)
+    }
+}