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ast: Remove some indirection layers from values in key-value attributes

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This commit is contained in:
Vadim Petrochenkov 2020-12-19 23:38:22 +03:00
parent ef589490a7
commit 71cd6f42a6
12 changed files with 72 additions and 50 deletions
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15
compiler/rustc_ast/src/ast.rs
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@ -23,8 +23,8 @@
pub use UnsafeSource::*;
use crate::ptr::P;
use crate::token::{self, CommentKind, DelimToken};
use crate::tokenstream::{DelimSpan, LazyTokenStream, TokenStream};
use crate::token::{self, CommentKind, DelimToken, Token};
use crate::tokenstream::{DelimSpan, LazyTokenStream, TokenStream, TokenTree};
use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
use rustc_data_structures::stack::ensure_sufficient_stack;
@ -1464,8 +1464,8 @@ pub enum MacArgs {
Eq(
/// Span of the `=` token.
Span,
/// Token stream of the "value".
TokenStream,
/// "value" as a nonterminal token.
Token,
),
}
@ -1478,10 +1478,10 @@ pub fn delim(&self) -> DelimToken {
}
pub fn span(&self) -> Option<Span> {
match *self {
match self {
MacArgs::Empty => None,
MacArgs::Delimited(dspan, ..) => Some(dspan.entire()),
MacArgs::Eq(eq_span, ref tokens) => Some(eq_span.to(tokens.span().unwrap_or(eq_span))),
MacArgs::Eq(eq_span, token) => Some(eq_span.to(token.span)),
}
}
@ -1490,7 +1490,8 @@ pub fn span(&self) -> Option<Span> {
pub fn inner_tokens(&self) -> TokenStream {
match self {
MacArgs::Empty => TokenStream::default(),
MacArgs::Delimited(.., tokens) | MacArgs::Eq(.., tokens) => tokens.clone(),
MacArgs::Delimited(.., tokens) => tokens.clone(),
MacArgs::Eq(.., token) => TokenTree::Token(token.clone()).into(),
}
}

14
compiler/rustc_ast/src/attr/mod.rs
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@ -476,7 +476,7 @@ impl MetaItemKind {
pub fn mac_args(&self, span: Span) -> MacArgs {
match self {
MetaItemKind::Word => MacArgs::Empty,
MetaItemKind::NameValue(lit) => MacArgs::Eq(span, lit.token_tree().into()),
MetaItemKind::NameValue(lit) => MacArgs::Eq(span, lit.to_token()),
MetaItemKind::List(list) => {
let mut tts = Vec::new();
for (i, item) in list.iter().enumerate() {
@ -498,7 +498,10 @@ fn token_trees_and_spacings(&self, span: Span) -> Vec<TreeAndSpacing> {
match *self {
MetaItemKind::Word => vec![],
MetaItemKind::NameValue(ref lit) => {
vec![TokenTree::token(token::Eq, span).into(), lit.token_tree().into()]
vec![
TokenTree::token(token::Eq, span).into(),
TokenTree::Token(lit.to_token()).into(),
]
}
MetaItemKind::List(ref list) => {
let mut tokens = Vec::new();
@ -554,10 +557,7 @@ fn from_mac_args(args: &MacArgs) -> Option<MetaItemKind> {
MetaItemKind::list_from_tokens(tokens.clone())
}
MacArgs::Delimited(..) => None,
MacArgs::Eq(_, tokens) => {
assert!(tokens.len() == 1);
MetaItemKind::name_value_from_tokens(&mut tokens.trees())
}
MacArgs::Eq(_, token) => Lit::from_token(token).ok().map(MetaItemKind::NameValue),
MacArgs::Empty => Some(MetaItemKind::Word),
}
}
@ -592,7 +592,7 @@ pub fn span(&self) -> Span {
fn token_trees_and_spacings(&self) -> Vec<TreeAndSpacing> {
match *self {
NestedMetaItem::MetaItem(ref item) => item.token_trees_and_spacings(),
NestedMetaItem::Literal(ref lit) => vec![lit.token_tree().into()],
NestedMetaItem::Literal(ref lit) => vec![TokenTree::Token(lit.to_token()).into()],
}
}

12
compiler/rustc_ast/src/mut_visit.rs
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@ -365,21 +365,19 @@ pub fn visit_mac_args<T: MutVisitor>(args: &mut MacArgs, vis: &mut T) {
visit_delim_span(dspan, vis);
visit_tts(tokens, vis);
}
MacArgs::Eq(eq_span, tokens) => {
MacArgs::Eq(eq_span, token) => {
vis.visit_span(eq_span);
visit_tts(tokens, vis);
if vis.token_visiting_enabled() {
visit_token(token, vis);
} else {
// The value in `#[key = VALUE]` must be visited as an expression for backward
// compatibility, so that macros can be expanded in that position.
if !vis.token_visiting_enabled() {
match Lrc::make_mut(&mut tokens.0).get_mut(0) {
Some((TokenTree::Token(token), _spacing)) => match &mut token.kind {
match &mut token.kind {
token::Interpolated(nt) => match Lrc::make_mut(nt) {
token::NtExpr(expr) => vis.visit_expr(expr),
t => panic!("unexpected token in key-value attribute: {:?}", t),
},
t => panic!("unexpected token in key-value attribute: {:?}", t),
},
t => panic!("unexpected token in key-value attribute: {:?}", t),
}
}
}

9
compiler/rustc_ast/src/util/literal.rs
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@ -2,7 +2,6 @@
use crate::ast::{self, Lit, LitKind};
use crate::token::{self, Token};
use crate::tokenstream::TokenTree;
use rustc_lexer::unescape::{unescape_byte, unescape_char};
use rustc_lexer::unescape::{unescape_byte_literal, unescape_literal, Mode};
@ -225,13 +224,13 @@ pub fn from_lit_kind(kind: LitKind, span: Span) -> Lit {
Lit { token: kind.to_lit_token(), kind, span }
}
/// Losslessly convert an AST literal into a token stream.
pub fn token_tree(&self) -> TokenTree {
let token = match self.token.kind {
/// Losslessly convert an AST literal into a token.
pub fn to_token(&self) -> Token {
let kind = match self.token.kind {
token::Bool => token::Ident(self.token.symbol, false),
_ => token::Literal(self.token),
};
TokenTree::token(token, self.span)
Token::new(kind, self.span)
}
}

6
compiler/rustc_ast/src/visit.rs
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@ -15,7 +15,6 @@
use crate::ast::*;
use crate::token;
use crate::tokenstream::TokenTree;
use rustc_span::symbol::{Ident, Symbol};
use rustc_span::Span;
@ -905,15 +904,12 @@ pub fn walk_mac_args<'a, V: Visitor<'a>>(visitor: &mut V, args: &'a MacArgs) {
MacArgs::Delimited(_dspan, _delim, _tokens) => {}
// The value in `#[key = VALUE]` must be visited as an expression for backward
// compatibility, so that macros can be expanded in that position.
MacArgs::Eq(_eq_span, tokens) => match tokens.trees_ref().next() {
Some(TokenTree::Token(token)) => match &token.kind {
MacArgs::Eq(_eq_span, token) => match &token.kind {
token::Interpolated(nt) => match &**nt {
token::NtExpr(expr) => visitor.visit_expr(expr),
t => panic!("unexpected token in key-value attribute: {:?}", t),
},
t => panic!("unexpected token in key-value attribute: {:?}", t),
},
t => panic!("unexpected token in key-value attribute: {:?}", t),
},
}
}

34
compiler/rustc_ast_lowering/src/lib.rs
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@ -1013,10 +1013,36 @@ fn lower_mac_args(&mut self, args: &MacArgs) -> MacArgs {
// This is an inert key-value attribute - it will never be visible to macros
// after it gets lowered to HIR. Therefore, we can synthesize tokens with fake
// spans to handle nonterminals in `#[doc]` (e.g. `#[doc = $e]`).
MacArgs::Eq(eq_span, ref tokens) => MacArgs::Eq(
eq_span,
self.lower_token_stream(tokens.clone(), CanSynthesizeMissingTokens::Yes),
),
MacArgs::Eq(eq_span, ref token) => {
// In valid code the value is always representable as a single literal token.
fn unwrap_single_token(sess: &Session, tokens: TokenStream, span: Span) -> Token {
if tokens.len() != 1 {
sess.diagnostic()
.delay_span_bug(span, "multiple tokens in key-value attribute's value");
}
match tokens.into_trees().next() {
Some(TokenTree::Token(token)) => token,
Some(TokenTree::Delimited(_, delim, tokens)) => {
if delim != token::NoDelim {
sess.diagnostic().delay_span_bug(
span,
"unexpected delimiter in key-value attribute's value",
)
}
unwrap_single_token(sess, tokens, span)
}
None => Token::dummy(),
}
}
let tokens = TokenStreamLowering {
parse_sess: &self.sess.parse_sess,
synthesize_tokens: CanSynthesizeMissingTokens::Yes,
nt_to_tokenstream: self.nt_to_tokenstream,
}
.lower_token(token.clone());
MacArgs::Eq(eq_span, unwrap_single_token(self.sess, tokens, token.span))
}
}
}

5
compiler/rustc_ast_pretty/src/pprust/state.rs
View File

@ -445,10 +445,11 @@ fn print_attr_item(&mut self, item: &ast::AttrItem, span: Span) {
),
MacArgs::Empty | MacArgs::Eq(..) => {
self.print_path(&item.path, false, 0);
if let MacArgs::Eq(_, tokens) = &item.args {
if let MacArgs::Eq(_, token) = &item.args {
self.space();
self.word_space("=");
self.print_tts(tokens, true);
let token_str = self.token_to_string_ext(token, true);
self.word(token_str);
}
}
}

4
compiler/rustc_parse/src/parser/mod.rs
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@ -983,8 +983,8 @@ fn parse_mac_args_common(&mut self, delimited_only: bool) -> PResult<'a, MacArgs
_ => self.sess.gated_spans.gate(sym::extended_key_value_attributes, span),
}
let token = token::Interpolated(Lrc::new(token::NtExpr(expr)));
MacArgs::Eq(eq_span, TokenTree::token(token, span).into())
let token_kind = token::Interpolated(Lrc::new(token::NtExpr(expr)));
MacArgs::Eq(eq_span, Token::new(token_kind, span))
} else {
MacArgs::Empty
}

5
compiler/rustc_parse/src/validate_attr.rs
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@ -2,7 +2,7 @@
use crate::parse_in;
use rustc_ast::tokenstream::DelimSpan;
use rustc_ast::tokenstream::{DelimSpan, TokenTree};
use rustc_ast::{self as ast, Attribute, MacArgs, MacDelimiter, MetaItem, MetaItemKind};
use rustc_errors::{Applicability, PResult};
use rustc_feature::{AttributeTemplate, BUILTIN_ATTRIBUTE_MAP};
@ -45,7 +45,8 @@ pub fn parse_meta<'a>(sess: &'a ParseSess, attr: &Attribute) -> PResult<'a, Meta
kind: match &item.args {
MacArgs::Empty => MetaItemKind::Word,
MacArgs::Eq(_, t) => {
let v = parse_in(sess, t.clone(), "name value", |p| p.parse_unsuffixed_lit())?;
let t = TokenTree::Token(t.clone()).into();
let v = parse_in(sess, t, "name value", |p| p.parse_unsuffixed_lit())?;
MetaItemKind::NameValue(v)
}
MacArgs::Delimited(dspan, delim, t) => {

2
src/test/ui/ast-json/ast-json-noexpand-output.stdout
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@ -1 +1 @@
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2
src/test/ui/ast-json/ast-json-output.stdout
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@ -1 +1 @@
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2
src/tools/clippy/clippy_lints/src/utils/ast_utils.rs
View File

@ -556,7 +556,7 @@ pub fn eq_mac_args(l: &MacArgs, r: &MacArgs) -> bool {
match (l, r) {
(Empty, Empty) => true,
(Delimited(_, ld, lts), Delimited(_, rd, rts)) => ld == rd && lts.eq_unspanned(rts),
(Eq(_, lts), Eq(_, rts)) => lts.eq_unspanned(rts),
(Eq(_, lt), Eq(_, rt)) => lt.kind == rt.kind,
_ => false,
}
}