From 0357257b72b9019b1c24ffd37ebc163c3d1bc6cb Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Mon, 14 Sep 2020 18:59:41 -0700
Subject: [PATCH 1/2] Allow path as value in name-value attribute
---
compiler/rustc_parse/src/parser/attr.rs | 8 ++-
compiler/rustc_parse/src/parser/mod.rs | 22 +++++--
src/test/ui/attr-eq-token-tree.rs | 2 +-
src/test/ui/attr-eq-token-tree.stderr | 2 +-
src/test/ui/attributes/path-eq-path.rs | 11 ++++
src/test/ui/attributes/path-eq-path.stderr | 14 +++++
src/test/ui/macros/macro-attribute.rs | 2 +-
src/test/ui/macros/macro-attribute.stderr | 2 +-
src/test/ui/parser/attr-bad-meta-2.rs | 2 +-
src/test/ui/parser/attr-bad-meta-2.stderr | 2 +-
src/test/ui/proc-macro/attributes-included.rs | 1 +
.../ui/proc-macro/attributes-included.stderr | 2 +-
.../auxiliary/attributes-included.rs | 58 ++++++++++++++++++-
13 files changed, 114 insertions(+), 14 deletions(-)
create mode 100644 src/test/ui/attributes/path-eq-path.rs
create mode 100644 src/test/ui/attributes/path-eq-path.stderr
diff --git a/compiler/rustc_parse/src/parser/attr.rs b/compiler/rustc_parse/src/parser/attr.rs
index 053b7e0b75fe4..e46c39bef04db 100644
--- a/compiler/rustc_parse/src/parser/attr.rs
+++ b/compiler/rustc_parse/src/parser/attr.rs
@@ -159,6 +159,7 @@ impl<'a> Parser<'a> {
/// PATH `{` TOKEN_STREAM `}`
/// PATH
/// PATH `=` UNSUFFIXED_LIT
+ /// PATH `=` PATH
/// The delimiters or `=` are still put into the resulting token stream.
pub fn parse_attr_item(&mut self, capture_tokens: bool) -> PResult<'a, ast::AttrItem> {
let item = match self.token.kind {
@@ -230,6 +231,11 @@ impl<'a> Parser<'a> {
crate fn parse_unsuffixed_lit(&mut self) -> PResult<'a, ast::Lit> {
let lit = self.parse_lit()?;
+ self.require_unsuffixed(&lit);
+ Ok(lit)
+ }
+
+ crate fn require_unsuffixed(&self, lit: &ast::Lit) {
debug!("checking if {:?} is unusuffixed", lit);
if !lit.kind.is_unsuffixed() {
@@ -240,8 +246,6 @@ impl<'a> Parser<'a> {
)
.emit();
}
-
- Ok(lit)
}
/// Parses `cfg_attr(pred, attr_item_list)` where `attr_item_list` is comma-delimited.
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs
index da1c54e88b5e2..f9cb42d56767c 100644
--- a/compiler/rustc_parse/src/parser/mod.rs
+++ b/compiler/rustc_parse/src/parser/mod.rs
@@ -934,16 +934,22 @@ impl<'a> Parser<'a> {
is_interpolated_expr = true;
}
}
- let token_tree = if is_interpolated_expr {
+ let token_stream: TokenStream = if is_interpolated_expr {
// We need to accept arbitrary interpolated expressions to continue
// supporting things like `doc = $expr` that work on stable.
// Non-literal interpolated expressions are rejected after expansion.
- self.parse_token_tree()
+ self.parse_token_tree().into()
+ } else if let Some(lit) = self.parse_opt_lit() {
+ self.require_unsuffixed(&lit);
+ lit.token_tree().into()
+ } else if self.check(&token::ModSep) || self.token.ident().is_some() {
+ self.collect_tokens_only(|this| this.parse_path(PathStyle::Mod))?
} else {
- self.parse_unsuffixed_lit()?.token_tree()
+ let msg = "expected a literal or ::-separated path";
+ return Err(self.struct_span_err(self.token.span, msg));
};
- MacArgs::Eq(eq_span, token_tree.into())
+ MacArgs::Eq(eq_span, token_stream)
} else {
MacArgs::Empty
}
@@ -1254,6 +1260,14 @@ impl<'a> Parser<'a> {
Ok((ret, Some(LazyTokenStream::new(lazy_impl))))
}
+ fn collect_tokens_only<R>(
+ &mut self,
+ f: impl FnOnce(&mut Self) -> PResult<'a, R>,
+ ) -> PResult<'a, TokenStream> {
+ let (_ignored, tokens) = self.collect_tokens(f)?;
+ Ok(tokens)
+ }
+
/// `::{` or `::*`
fn is_import_coupler(&mut self) -> bool {
self.check(&token::ModSep)
diff --git a/src/test/ui/attr-eq-token-tree.rs b/src/test/ui/attr-eq-token-tree.rs
index c301492b9e21a..d9359da76ec30 100644
--- a/src/test/ui/attr-eq-token-tree.rs
+++ b/src/test/ui/attr-eq-token-tree.rs
@@ -1,2 +1,2 @@
-#[my_attr = !] //~ ERROR unexpected token: `!`
+#[my_attr = !] //~ ERROR expected a literal or ::-separated path
fn main() {}
diff --git a/src/test/ui/attr-eq-token-tree.stderr b/src/test/ui/attr-eq-token-tree.stderr
index bb37c2e0cc473..f4ad7f5a3944f 100644
--- a/src/test/ui/attr-eq-token-tree.stderr
+++ b/src/test/ui/attr-eq-token-tree.stderr
@@ -1,4 +1,4 @@
-error: unexpected token: `!`
+error: expected a literal or ::-separated path
--> $DIR/attr-eq-token-tree.rs:1:13
|
LL | #[my_attr = !]
diff --git a/src/test/ui/attributes/path-eq-path.rs b/src/test/ui/attributes/path-eq-path.rs
new file mode 100644
index 0000000000000..b189eb249ee68
--- /dev/null
+++ b/src/test/ui/attributes/path-eq-path.rs
@@ -0,0 +1,11 @@
+#[cfg(any())]
+extern "C++" {
+ #[namespace = std::experimental]
+ type any;
+
+ #[rust = std::option::Option<T>]
+ //~^ ERROR expected one of `::` or `]`, found `<`
+ type optional;
+}
+
+fn main() {}
diff --git a/src/test/ui/attributes/path-eq-path.stderr b/src/test/ui/attributes/path-eq-path.stderr
new file mode 100644
index 0000000000000..82603ff27e17c
--- /dev/null
+++ b/src/test/ui/attributes/path-eq-path.stderr
@@ -0,0 +1,14 @@
+error: expected one of `::` or `]`, found `<`
+ --> $DIR/path-eq-path.rs:6:33
+ |
+LL | extern "C++" {
+ | - while parsing this item list starting here
+...
+LL | #[rust = std::option::Option<T>]
+ | ^ expected one of `::` or `]`
+...
+LL | }
+ | - the item list ends here
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/macros/macro-attribute.rs b/src/test/ui/macros/macro-attribute.rs
index f580dfa8e34ed..c6656a975d68d 100644
--- a/src/test/ui/macros/macro-attribute.rs
+++ b/src/test/ui/macros/macro-attribute.rs
@@ -1,2 +1,2 @@
-#[doc = $not_there] //~ ERROR unexpected token: `$`
+#[doc = $not_there] //~ ERROR expected a literal or ::-separated path
fn main() { }
diff --git a/src/test/ui/macros/macro-attribute.stderr b/src/test/ui/macros/macro-attribute.stderr
index d28ce25341d3a..3a8a3abf2b883 100644
--- a/src/test/ui/macros/macro-attribute.stderr
+++ b/src/test/ui/macros/macro-attribute.stderr
@@ -1,4 +1,4 @@
-error: unexpected token: `$`
+error: expected a literal or ::-separated path
--> $DIR/macro-attribute.rs:1:9
|
LL | #[doc = $not_there]
diff --git a/src/test/ui/parser/attr-bad-meta-2.rs b/src/test/ui/parser/attr-bad-meta-2.rs
index cefd3369742be..a4232e8924cc5 100644
--- a/src/test/ui/parser/attr-bad-meta-2.rs
+++ b/src/test/ui/parser/attr-bad-meta-2.rs
@@ -1,2 +1,2 @@
-#[path =] //~ ERROR unexpected token: `]`
+#[path =] //~ ERROR expected a literal or ::-separated path
mod m {}
diff --git a/src/test/ui/parser/attr-bad-meta-2.stderr b/src/test/ui/parser/attr-bad-meta-2.stderr
index 2d772dae69125..9fb8f8a12289f 100644
--- a/src/test/ui/parser/attr-bad-meta-2.stderr
+++ b/src/test/ui/parser/attr-bad-meta-2.stderr
@@ -1,4 +1,4 @@
-error: unexpected token: `]`
+error: expected a literal or ::-separated path
--> $DIR/attr-bad-meta-2.rs:1:9
|
LL | #[path =]
diff --git a/src/test/ui/proc-macro/attributes-included.rs b/src/test/ui/proc-macro/attributes-included.rs
index 95e8e10a3ece9..fa9ead029c273 100644
--- a/src/test/ui/proc-macro/attributes-included.rs
+++ b/src/test/ui/proc-macro/attributes-included.rs
@@ -13,6 +13,7 @@ use attributes_included::*;
#[foo]
#[inline]
/// doc
+#[namespace = std::experimental]
fn foo() {
let a: i32 = "foo"; //~ WARN: unused variable
}
diff --git a/src/test/ui/proc-macro/attributes-included.stderr b/src/test/ui/proc-macro/attributes-included.stderr
index 72c88d5d8b752..1ce12e9f688ea 100644
--- a/src/test/ui/proc-macro/attributes-included.stderr
+++ b/src/test/ui/proc-macro/attributes-included.stderr
@@ -1,5 +1,5 @@
warning: unused variable: `a`
- --> $DIR/attributes-included.rs:17:9
+ --> $DIR/attributes-included.rs:18:9
|
LL | let a: i32 = "foo";
| ^ help: if this is intentional, prefix it with an underscore: `_a`
diff --git a/src/test/ui/proc-macro/auxiliary/attributes-included.rs b/src/test/ui/proc-macro/auxiliary/attributes-included.rs
index a5eb40b28dca4..05942d305c47a 100644
--- a/src/test/ui/proc-macro/auxiliary/attributes-included.rs
+++ b/src/test/ui/proc-macro/auxiliary/attributes-included.rs
@@ -6,20 +6,30 @@
extern crate proc_macro;
use proc_macro::{TokenStream, TokenTree, Delimiter, Literal, Spacing, Group};
+use std::iter;
#[proc_macro_attribute]
pub fn foo(attr: TokenStream, input: TokenStream) -> TokenStream {
assert!(attr.is_empty());
- let input = input.into_iter().collect::<Vec<_>>();
+ let mut input = input.into_iter().collect::<Vec<_>>();
+ let (namespace_start, namespace_end);
{
let mut cursor = &input[..];
assert_inline(&mut cursor);
assert_doc(&mut cursor);
assert_inline(&mut cursor);
assert_doc(&mut cursor);
+
+ // Splice out the #[namespace = ...] attribute as it is an inert
+ // attribute, not a proc macro.
+ namespace_start = input.len() - cursor.len();
+ assert_namespace(&mut cursor);
+ namespace_end = input.len() - cursor.len();
+
assert_foo(&mut cursor);
assert!(cursor.is_empty());
}
+ input.splice(namespace_start..namespace_end, iter::empty());
fold_stream(input.into_iter().collect())
}
@@ -34,6 +44,7 @@ pub fn bar(attr: TokenStream, input: TokenStream) -> TokenStream {
assert_invoc(&mut cursor);
assert_inline(&mut cursor);
assert_doc(&mut cursor);
+ assert_namespace(&mut cursor);
assert_foo(&mut cursor);
assert!(cursor.is_empty());
}
@@ -93,6 +104,51 @@ fn assert_doc(slice: &mut &[TokenTree]) {
*slice = &slice[2..];
}
+fn assert_namespace(slice: &mut &[TokenTree]) {
+ match &slice[0] {
+ TokenTree::Punct(tt) => assert_eq!(tt.as_char(), '#'),
+ _ => panic!("expected `#`"),
+ }
+ let inner = match &slice[1] {
+ TokenTree::Group(tt) => tt.stream().into_iter().collect::<Vec<_>>(),
+ _ => panic!("expected brackets"),
+ };
+ if inner.len() != 6 {
+ panic!("expected 6 tokens in namespace attr")
+ }
+ match &inner[0] {
+ TokenTree::Ident(tt) => assert_eq!("namespace", tt.to_string()),
+ _ => panic!("expected `namespace`"),
+ }
+ match &inner[1] {
+ TokenTree::Punct(tt) => assert_eq!(tt.as_char(), '='),
+ _ => panic!("expected `=`"),
+ }
+ match &inner[2] {
+ TokenTree::Ident(tt) => assert_eq!("std", tt.to_string()),
+ _ => panic!("expected `std`"),
+ }
+ match &inner[3] {
+ TokenTree::Punct(tt) => {
+ assert_eq!(tt.as_char(), ':');
+ assert_eq!(tt.spacing(), Spacing::Joint);
+ }
+ _ => panic!("expected `:`"),
+ }
+ match &inner[4] {
+ TokenTree::Punct(tt) => {
+ assert_eq!(tt.as_char(), ':');
+ assert_eq!(tt.spacing(), Spacing::Alone);
+ }
+ _ => panic!("expected `:`"),
+ }
+ match &inner[5] {
+ TokenTree::Ident(tt) => assert_eq!("experimental", tt.to_string()),
+ _ => panic!("expected `experimental`"),
+ }
+ *slice = &slice[2..];
+}
+
fn assert_invoc(slice: &mut &[TokenTree]) {
match &slice[0] {
TokenTree::Punct(tt) => assert_eq!(tt.as_char(), '#'),
From 543c10af1f474a0c26d3309148c40c9eaf640155 Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Mon, 2 Nov 2020 19:58:48 -0800
Subject: [PATCH 2/2] Resolve conflict with PR 77255
---
compiler/rustc_parse/src/parser/mod.rs | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs
index f9cb42d56767c..78fe0794f4acf 100644
--- a/compiler/rustc_parse/src/parser/mod.rs
+++ b/compiler/rustc_parse/src/parser/mod.rs
@@ -944,6 +944,8 @@ impl<'a> Parser<'a> {
lit.token_tree().into()
} else if self.check(&token::ModSep) || self.token.ident().is_some() {
self.collect_tokens_only(|this| this.parse_path(PathStyle::Mod))?
+ .expect("parse_path cannot parse empty path")
+ .create_token_stream()
} else {
let msg = "expected a literal or ::-separated path";
return Err(self.struct_span_err(self.token.span, msg));
@@ -1263,7 +1265,7 @@ impl<'a> Parser<'a> {
fn collect_tokens_only<R>(
&mut self,
f: impl FnOnce(&mut Self) -> PResult<'a, R>,
- ) -> PResult<'a, TokenStream> {
+ ) -> PResult<'a, Option<LazyTokenStream>> {
let (_ignored, tokens) = self.collect_tokens(f)?;
Ok(tokens)
}