Auto merge of #105166 - matthiaskrgr:rollup-s9l6vt2, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #104614 (Add `type_ascribe!` macro as placeholder syntax for type ascription)
 - #105126 (Make `VecDeque::new_in` unstably const)
 - #105132 (Migrate summary toggle filter to CSS variable)
 - #105136 (clarify comment on Deref promotion)
 - #105137 (Add tracking issue number for `file_create_new` feature)
 - #105143 (rustdoc: use simpler CSS for setting the font on scraped examples)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_builtin_macros/src/lib.rs

@@ -45,6 +45,7 @@ mod log_syntax;
 mod source_util;
 mod test;
 mod trace_macros;
+mod type_ascribe;
 mod util;
 
 pub mod asm;
@@ -92,6 +93,7 @@ pub fn register_builtin_macros(resolver: &mut dyn ResolverExpand) {
         unreachable: edition_panic::expand_unreachable,
         stringify: source_util::expand_stringify,
         trace_macros: trace_macros::expand_trace_macros,
+        type_ascribe: type_ascribe::expand_type_ascribe,
     }
 
     register_attr! {

compiler/rustc_builtin_macros/src/type_ascribe.rs

@@ -0,0 +1,35 @@
+use rustc_ast::ptr::P;
+use rustc_ast::tokenstream::TokenStream;
+use rustc_ast::{token, Expr, ExprKind, Ty};
+use rustc_errors::PResult;
+use rustc_expand::base::{self, DummyResult, ExtCtxt, MacEager};
+use rustc_span::Span;
+
+pub fn expand_type_ascribe(
+    cx: &mut ExtCtxt<'_>,
+    span: Span,
+    tts: TokenStream,
+) -> Box<dyn base::MacResult + 'static> {
+    let (expr, ty) = match parse_ascribe(cx, tts) {
+        Ok(parsed) => parsed,
+        Err(mut err) => {
+            err.emit();
+            return DummyResult::any(span);
+        }
+    };
+
+    let asc_expr = cx.expr(span, ExprKind::Type(expr, ty));
+
+    return MacEager::expr(asc_expr);
+}
+
+fn parse_ascribe<'a>(cx: &mut ExtCtxt<'a>, stream: TokenStream) -> PResult<'a, (P<Expr>, P<Ty>)> {
+    let mut parser = cx.new_parser_from_tts(stream);
+
+    let expr = parser.parse_expr()?;
+    parser.expect(&token::Comma)?;
+
+    let ty = parser.parse_ty()?;
+
+    Ok((expr, ty))
+}

compiler/rustc_const_eval/src/transform/promote_consts.rs

@@ -318,14 +318,14 @@ impl<'tcx> Validator<'_, 'tcx> {
                 match elem {
                     ProjectionElem::Deref => {
                         let mut promotable = false;
+                        // When a static is used by-value, that gets desugared to `*STATIC_ADDR`,
+                        // and we need to be able to promote this. So check if this deref matches
+                        // that specific pattern.
+
                         // We need to make sure this is a `Deref` of a local with no further projections.
                         // Discussion can be found at
                         // https://github.com/rust-lang/rust/pull/74945#discussion_r463063247
                         if let Some(local) = place_base.as_local() {
-                            // This is a special treatment for cases like *&STATIC where STATIC is a
-                            // global static variable.
-                            // This pattern is generated only when global static variables are directly
-                            // accessed and is qualified for promotion safely.
                             if let TempState::Defined { location, .. } = self.temps[local] {
                                 let def_stmt = self.body[location.block]
                                     .statements

compiler/rustc_span/src/symbol.rs

@@ -1488,6 +1488,7 @@ symbols! {
         ty,
         type_alias_enum_variants,
         type_alias_impl_trait,
+        type_ascribe,
         type_ascription,
         type_changing_struct_update,
         type_id,

library/alloc/src/collections/vec_deque/mod.rs

@@ -566,10 +566,9 @@ impl<T, A: Allocator> VecDeque<T, A> {
     ///
     /// let deque: VecDeque<u32> = VecDeque::new();
     /// ```
-    // FIXME: This should probably be const
     #[inline]
     #[unstable(feature = "allocator_api", issue = "32838")]
-    pub fn new_in(alloc: A) -> VecDeque<T, A> {
+    pub const fn new_in(alloc: A) -> VecDeque<T, A> {
         VecDeque { head: 0, len: 0, buf: RawVec::new_in(alloc) }
     }
 
@@ -2152,7 +2151,7 @@ impl<T, A: Allocator> VecDeque<T, A> {
 
             self.head = tail;
         } else {
-            // ´free` is smaller than both `head_len` and `tail_len`.
+            // `free` is smaller than both `head_len` and `tail_len`.
             // the general algorithm for this first moves the slices
             // right next to each other and then uses `slice::rotate`
             // to rotate them into place:

library/core/src/macros/mod.rs

@@ -1546,6 +1546,18 @@ pub(crate) mod builtin {
         /* compiler built-in */
     }
 
+    /// Unstable placeholder for type ascription.
+    #[rustc_builtin_macro]
+    #[unstable(
+        feature = "type_ascription",
+        issue = "23416",
+        reason = "placeholder syntax for type ascription"
+    )]
+    #[cfg(not(bootstrap))]
+    pub macro type_ascribe($expr:expr, $ty:ty) {
+        /* compiler built-in */
+    }
+
     /// Unstable implementation detail of the `rustc` compiler, do not use.
     #[rustc_builtin_macro]
     #[stable(feature = "rust1", since = "1.0.0")]

library/core/src/prelude/v1.rs

@@ -98,3 +98,11 @@ pub use crate::macros::builtin::cfg_accessible;
     reason = "`cfg_eval` is a recently implemented feature"
 )]
 pub use crate::macros::builtin::cfg_eval;
+
+#[unstable(
+    feature = "type_ascription",
+    issue = "23416",
+    reason = "placeholder syntax for type ascription"
+)]
+#[cfg(not(bootstrap))]
+pub use crate::macros::builtin::type_ascribe;

library/std/src/fs.rs

@@ -401,7 +401,7 @@ impl File {
     ///     Ok(())
     /// }
     /// ```
-    #[unstable(feature = "file_create_new", issue = "none")]
+    #[unstable(feature = "file_create_new", issue = "105135")]
     pub fn create_new<P: AsRef<Path>>(path: P) -> io::Result<File> {
         OpenOptions::new().read(true).write(true).create_new(true).open(path.as_ref())
     }

library/std/src/prelude/v1.rs

@@ -85,6 +85,15 @@ pub use core::prelude::v1::cfg_accessible;
 )]
 pub use core::prelude::v1::cfg_eval;
 
+// Do not `doc(no_inline)` either.
+#[unstable(
+    feature = "type_ascription",
+    issue = "23416",
+    reason = "placeholder syntax for type ascription"
+)]
+#[cfg(not(bootstrap))]
+pub use core::prelude::v1::type_ascribe;
+
 // The file so far is equivalent to src/libcore/prelude/v1.rs,
 // and below to src/liballoc/prelude.rs.
 // Those files are duplicated rather than using glob imports

src/librustdoc/html/static/css/rustdoc.css

@@ -197,9 +197,7 @@ a.srclink,
 #help-button > a,
 details.rustdoc-toggle.top-doc > summary,
 details.rustdoc-toggle.non-exhaustive > summary,
-.scraped-example-title,
-.more-examples-toggle summary, .more-examples-toggle .hide-more,
-.example-links a,
+.scraped-example-list,
 /* This selector is for the items listed in the "all items" page. */
 ul.all-items {
 	font-family: "Fira Sans", Arial, NanumBarunGothic, sans-serif;
@@ -1516,6 +1514,7 @@ details.rustdoc-toggle > summary::before {
 	display: inline-block;
 	vertical-align: middle;
 	opacity: .5;
+	filter: var(--toggle-filter);
 }
 
 details.rustdoc-toggle > summary.hideme > span,

src/librustdoc/html/static/css/themes/ayu.css

@@ -21,6 +21,7 @@ Original by Dempfi (https://github.com/dempfi/ayu)
 	--right-side-color: grey;
 	--code-attribute-color: #999;
 	--toggles-color: #999;
+	--toggle-filter: invert(100%);
 	--search-input-focused-border-color: #5c6773; /* Same as `--border-color`. */
 	--copy-path-button-color: #fff;
 	--copy-path-img-filter: invert(70%);
@@ -158,10 +159,6 @@ body.source .example-wrap pre.rust a {
 	background: #333;
 }
 
-details.rustdoc-toggle > summary::before {
-	filter: invert(100%);
-}
-
 .module-item .stab,
 .import-item .stab {
 	color: #000;

src/librustdoc/html/static/css/themes/dark.css

@@ -16,6 +16,7 @@
 	--right-side-color: grey;
 	--code-attribute-color: #999;
 	--toggles-color: #999;
+	--toggle-filter: invert(100%);
 	--search-input-focused-border-color: #008dfd;
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
@@ -89,10 +90,6 @@ body.source .example-wrap pre.rust a {
 	background: #333;
 }
 
-details.rustdoc-toggle > summary::before {
-	filter: invert(100%);
-}
-
 #titles > button:not(.selected) {
 	background-color: #252525;
 	border-top-color: #252525;

src/librustdoc/html/static/css/themes/light.css

@@ -16,6 +16,7 @@
 	--right-side-color: grey;
 	--code-attribute-color: #999;
 	--toggles-color: #999;
+	--toggle-filter: none;
 	--search-input-focused-border-color: #66afe9;
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);

src/test/rustdoc-gui/scrape-examples-fonts.goml

@@ -0,0 +1,8 @@
+goto: "file://" + |DOC_PATH| + "/scrape_examples/fn.test_many.html"
+
+store-value: (font, '"Fira Sans", Arial, NanumBarunGothic, sans-serif')
+
+wait-for-css: (".scraped-example-title", {"font-family": |font|})
+wait-for-css: (".more-examples-toggle summary", {"font-family": |font|})
+wait-for-css: (".more-examples-toggle .hide-more", {"font-family": |font|})
+wait-for-css: (".example-links a", {"font-family": |font|})

src/test/rustdoc-gui/src/scrape_examples/examples/check-many-1.rs

@@ -0,0 +1,3 @@
+fn main() {
+    scrape_examples::test_many();
+}

src/test/rustdoc-gui/src/scrape_examples/examples/check-many-2.rs

@@ -0,0 +1,3 @@
+fn main() {
+    scrape_examples::test_many();
+}

src/test/rustdoc-gui/src/scrape_examples/examples/check-many-3.rs

@@ -0,0 +1,3 @@
+fn main() {
+    scrape_examples::test_many();
+}

src/test/rustdoc-gui/src/scrape_examples/examples/check-many-4.rs

@@ -0,0 +1,3 @@
+fn main() {
+    scrape_examples::test_many();
+}

src/test/rustdoc-gui/src/scrape_examples/examples/check-many-5.rs

@@ -0,0 +1,3 @@
+fn main() {
+    scrape_examples::test_many();
+}

src/test/rustdoc-gui/src/scrape_examples/examples/check-many-6.rs

@@ -0,0 +1,3 @@
+fn main() {
+    scrape_examples::test_many();
+}

src/test/rustdoc-gui/src/scrape_examples/examples/check-many-7.rs

@@ -0,0 +1,3 @@
+fn main() {
+    scrape_examples::test_many();
+}

src/test/rustdoc-gui/src/scrape_examples/src/lib.rs

@@ -5,3 +5,5 @@
 /// test();
 /// ```
 pub fn test() {}
+
+pub fn test_many() {}

src/test/rustdoc-gui/toggle-docs.goml

@@ -40,3 +40,32 @@ assert-attribute-false: (
 click: "#toggle-all-docs"
 wait-for-text: ("#toggle-all-docs", "[−]")
 assert-attribute: ("details.rustdoc-toggle", {"open": ""}, ALL)
+
+// Checking the toggles style.
+show-text: true
+define-function: (
+    "check-color",
+    (theme, filter),
+    [
+        // Setting the theme.
+	("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        // We reload the page so the local storage settings are being used.
+        ("reload"),
+
+        ("assert-css", ("details.rustdoc-toggle > summary::before", {
+            "opacity": "0.5",
+            "filter": |filter|,
+        }, ALL)),
+        ("move-cursor-to", "details.rustdoc-toggle summary"),
+        ("assert-css", ("details.rustdoc-toggle > summary:hover::before", {
+            "opacity": "1",
+            "filter": |filter|,
+        })),
+        // moving the cursor somewhere else to not mess with next function calls.
+        ("move-cursor-to", ".search-input"),
+    ]
+)
+
+call-function: ("check-color", {"theme": "ayu", "filter": "invert(1)"})
+call-function: ("check-color", {"theme": "dark", "filter": "invert(1)"})
+call-function: ("check-color", {"theme": "light", "filter": "none"})

src/test/ui/associated-consts/issue-93835.rs

@@ -1,9 +1,11 @@
+#![feature(type_ascription)]
+
 fn e() {
-    p:a<p:p<e=6>>
-    //~^ ERROR comparison operators
+    type_ascribe!(p, a<p:p<e=6>>);
+    //~^ ERROR cannot find type `a` in this scope
     //~| ERROR cannot find value
     //~| ERROR associated const equality
-    //~| ERROR associated const equality
+    //~| ERROR cannot find trait `p` in this scope
     //~| ERROR associated type bounds
 }
 

src/test/ui/associated-consts/issue-93835.stderr

@@ -1,65 +1,40 @@
-error: comparison operators cannot be chained
-  --> $DIR/issue-93835.rs:2:8
-   |
-LL | fn e() {
-   |        - while parsing this struct
-LL |     p:a<p:p<e=6>>
-   |        ^        ^
-   |
-   = help: use `::<...>` instead of `<...>` to specify lifetime, type, or const arguments
-   = help: or use `(...)` if you meant to specify fn arguments
-
 error[E0425]: cannot find value `p` in this scope
-  --> $DIR/issue-93835.rs:2:5
-   |
-LL |     p:a<p:p<e=6>>
-   |     ^ not found in this scope
-   |
-help: you might have meant to write a `struct` literal
-   |
-LL ~ fn e() { SomeStruct {
-LL |     p:a<p:p<e=6>>
- ...
-LL |
-LL ~ }}
+  --> $DIR/issue-93835.rs:4:19
    |
-help: maybe you meant to write a path separator here
-   |
-LL |     p::a<p:p<e=6>>
-   |      ~~
-help: maybe you meant to write an assignment here
-   |
-LL |     let p:a<p:p<e=6>>
-   |     ~~~~~
+LL |     type_ascribe!(p, a<p:p<e=6>>);
+   |                   ^ not found in this scope
 
-error[E0658]: associated const equality is incomplete
-  --> $DIR/issue-93835.rs:2:13
+error[E0412]: cannot find type `a` in this scope
+  --> $DIR/issue-93835.rs:4:22
    |
-LL |     p:a<p:p<e=6>>
-   |             ^^^
+LL |     type_ascribe!(p, a<p:p<e=6>>);
+   |                      ^ not found in this scope
+
+error[E0405]: cannot find trait `p` in this scope
+  --> $DIR/issue-93835.rs:4:26
    |
-   = note: see issue #92827 <https://github.com/rust-lang/rust/issues/92827> for more information
-   = help: add `#![feature(associated_const_equality)]` to the crate attributes to enable
+LL |     type_ascribe!(p, a<p:p<e=6>>);
+   |                          ^ not found in this scope
 
 error[E0658]: associated const equality is incomplete
-  --> $DIR/issue-93835.rs:2:13
+  --> $DIR/issue-93835.rs:4:28
    |
-LL |     p:a<p:p<e=6>>
-   |             ^^^
+LL |     type_ascribe!(p, a<p:p<e=6>>);
+   |                            ^^^
    |
    = note: see issue #92827 <https://github.com/rust-lang/rust/issues/92827> for more information
    = help: add `#![feature(associated_const_equality)]` to the crate attributes to enable
 
 error[E0658]: associated type bounds are unstable
-  --> $DIR/issue-93835.rs:2:9
+  --> $DIR/issue-93835.rs:4:24
    |
-LL |     p:a<p:p<e=6>>
-   |         ^^^^^^^^
+LL |     type_ascribe!(p, a<p:p<e=6>>);
+   |                        ^^^^^^^^
    |
    = note: see issue #52662 <https://github.com/rust-lang/rust/issues/52662> for more information
    = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable
 
 error: aborting due to 5 previous errors
 
-Some errors have detailed explanations: E0425, E0658.
-For more information about an error, try `rustc --explain E0425`.
+Some errors have detailed explanations: E0405, E0412, E0425, E0658.
+For more information about an error, try `rustc --explain E0405`.