Rollup of 8 pull requests

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -1857,12 +1857,37 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
                 }
             }
             GeneratorInteriorOrUpvar::Upvar(upvar_span) => {
+                // `Some(ref_ty)` if `target_ty` is `&T` and `T` fails to impl `Sync`
+                let refers_to_non_sync = match target_ty.kind() {
+                    ty::Ref(_, ref_ty, _) => match self.evaluate_obligation(&obligation) {
+                        Ok(eval) if !eval.may_apply() => Some(ref_ty),
+                        _ => None,
+                    },
+                    _ => None,
+                };
+
+                let (span_label, span_note) = match refers_to_non_sync {
+                    // if `target_ty` is `&T` and `T` fails to impl `Sync`,
+                    // include suggestions to make `T: Sync` so that `&T: Send`
+                    Some(ref_ty) => (
+                        format!(
+                            "has type `{}` which {}, because `{}` is not `Sync`",
+                            target_ty, trait_explanation, ref_ty
+                        ),
+                        format!(
+                            "captured value {} because `&` references cannot be sent unless their referent is `Sync`",
+                            trait_explanation
+                        ),
+                    ),
+                    None => (
+                        format!("has type `{}` which {}", target_ty, trait_explanation),
+                        format!("captured value {}", trait_explanation),
+                    ),
+                };
+
                 let mut span = MultiSpan::from_span(upvar_span);
-                span.push_span_label(
-                    upvar_span,
-                    format!("has type `{}` which {}", target_ty, trait_explanation),
-                );
-                err.span_note(span, &format!("captured value {}", trait_explanation));
+                span.push_span_label(upvar_span, span_label);
+                err.span_note(span, &span_note);
             }
         }
 

compiler/rustc_typeck/src/check/wfcheck.rs

@@ -523,8 +523,7 @@ fn check_type_defn<'tcx, F>(
                 fcx.register_wf_obligation(
                     field.ty.into(),
                     field.span,
-                    // We don't have an HIR id for the field
-                    ObligationCauseCode::WellFormed(None),
+                    ObligationCauseCode::WellFormed(Some(WellFormedLoc::Ty(field.def_id))),
                 )
             }
 
@@ -1467,6 +1466,7 @@ struct AdtVariant<'tcx> {
 
 struct AdtField<'tcx> {
     ty: Ty<'tcx>,
+    def_id: LocalDefId,
     span: Span,
 }
 
@@ -1477,11 +1477,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             .fields()
             .iter()
             .map(|field| {
-                let field_ty = self.tcx.type_of(self.tcx.hir().local_def_id(field.hir_id));
+                let def_id = self.tcx.hir().local_def_id(field.hir_id);
+                let field_ty = self.tcx.type_of(def_id);
                 let field_ty = self.normalize_associated_types_in(field.ty.span, field_ty);
                 let field_ty = self.resolve_vars_if_possible(field_ty);
                 debug!("non_enum_variant: type of field {:?} is {:?}", field, field_ty);
-                AdtField { ty: field_ty, span: field.ty.span }
+                AdtField { ty: field_ty, span: field.ty.span, def_id }
             })
             .collect();
         AdtVariant { fields, explicit_discr: None }

compiler/rustc_typeck/src/hir_wf_check.rs

@@ -25,7 +25,7 @@ fn diagnostic_hir_wf_check<'tcx>(
         WellFormedLoc::Ty(def_id) => def_id,
         WellFormedLoc::Param { function, param_idx: _ } => function,
     };
-    let hir_id = HirId::make_owner(def_id);
+    let hir_id = hir.local_def_id_to_hir_id(def_id);
 
     // HIR wfcheck should only ever happen as part of improving an existing error
     tcx.sess
@@ -140,6 +140,7 @@ fn diagnostic_hir_wf_check<'tcx>(
                 }
                 ref item => bug!("Unexpected item {:?}", item),
             },
+            hir::Node::Field(field) => Some(field.ty),
             ref node => bug!("Unexpected node {:?}", node),
         },
         WellFormedLoc::Param { function: _, param_idx } => {

src/bootstrap/flags.rs

@@ -152,7 +152,7 @@ Subcommands:
     fmt         Run rustfmt
     test, t     Build and run some test suites
     bench       Build and run some benchmarks
-    doc         Build documentation
+    doc, d      Build documentation
     clean       Clean out build directories
     dist        Build distribution artifacts
     install     Install distribution artifacts
@@ -244,6 +244,7 @@ To learn more about a subcommand, run `./x.py <subcommand> -h`",
                 || (s == "t")
                 || (s == "bench")
                 || (s == "doc")
+                || (s == "d")
                 || (s == "clean")
                 || (s == "dist")
                 || (s == "install")
@@ -312,7 +313,7 @@ To learn more about a subcommand, run `./x.py <subcommand> -h`",
             "clippy" => {
                 opts.optflag("", "fix", "automatically apply lint suggestions");
             }
-            "doc" => {
+            "doc" | "d" => {
                 opts.optflag("", "open", "open the docs in a browser");
             }
             "clean" => {
@@ -487,7 +488,7 @@ Arguments:
         ./x.py test --stage 1",
                 );
             }
-            "doc" => {
+            "doc" | "d" => {
                 subcommand_help.push_str(
                     "\n
 Arguments:
@@ -573,7 +574,7 @@ Arguments:
                 },
             },
             "bench" => Subcommand::Bench { paths, test_args: matches.opt_strs("test-args") },
-            "doc" => Subcommand::Doc { paths, open: matches.opt_present("open") },
+            "doc" | "d" => Subcommand::Doc { paths, open: matches.opt_present("open") },
             "clean" => {
                 if !paths.is_empty() {
                     println!("\nclean does not take a path argument\n");

src/librustdoc/doctest.rs

@@ -105,7 +105,7 @@ crate fn run(options: Options) -> Result<(), ErrorReported> {
         registry: rustc_driver::diagnostics_registry(),
     };
 
-    let mut test_args = options.test_args.clone();
+    let test_args = options.test_args.clone();
     let display_warnings = options.display_warnings;
     let nocapture = options.nocapture;
     let externs = options.externs.clone();
@@ -166,12 +166,7 @@ crate fn run(options: Options) -> Result<(), ErrorReported> {
         Err(ErrorReported) => return Err(ErrorReported),
     };
 
-    test_args.insert(0, "rustdoctest".to_string());
-    if nocapture {
-        test_args.push("--nocapture".to_string());
-    }
-
-    test::test_main(&test_args, tests, Some(test::Options::new().display_output(display_warnings)));
+    run_tests(test_args, nocapture, display_warnings, tests);
 
     // Collect and warn about unused externs, but only if we've gotten
     // reports for each doctest
@@ -214,6 +209,19 @@ crate fn run(options: Options) -> Result<(), ErrorReported> {
     Ok(())
 }
 
+crate fn run_tests(
+    mut test_args: Vec<String>,
+    nocapture: bool,
+    display_warnings: bool,
+    tests: Vec<test::TestDescAndFn>,
+) {
+    test_args.insert(0, "rustdoctest".to_string());
+    if nocapture {
+        test_args.push("--nocapture".to_string());
+    }
+    test::test_main(&test_args, tests, Some(test::Options::new().display_output(display_warnings)));
+}
+
 // Look for `#![doc(test(no_crate_inject))]`, used by crates in the std facade.
 fn scrape_test_config(attrs: &[ast::Attribute]) -> TestOptions {
     use rustc_ast_pretty::pprust;

src/librustdoc/html/render/print_item.rs

@@ -1029,14 +1029,12 @@ fn item_enum(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, e: &clean::Enum
 
             use crate::clean::Variant;
             if let clean::VariantItem(Variant::Struct(ref s)) = *variant.kind {
-                let count_fields = s.fields.len();
-                toggle_open(w, format_args!("{} field{}", count_fields, pluralize(count_fields)));
                 let variant_id = cx.derive_id(format!(
                     "{}.{}.fields",
                     ItemType::Variant,
                     variant.name.as_ref().unwrap()
                 ));
-                write!(w, "<div class=\"autohide sub-variant\" id=\"{id}\">", id = variant_id);
+                write!(w, "<div class=\"sub-variant\" id=\"{id}\">", id = variant_id);
                 write!(
                     w,
                     "<h3>Fields of <b>{name}</b></h3><div>",
@@ -1064,7 +1062,6 @@ fn item_enum(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, e: &clean::Enum
                     }
                 }
                 w.write_str("</div></div>");
-                toggle_close(w);
             }
         }
     }

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

@@ -329,6 +329,7 @@ nav.sub {
 .logo-container > img {
 	max-width: 100px;
 	max-height: 100px;
+	height: 100%;
 	position: absolute;
 	left: 50%;
 	top: 50%;
@@ -1072,7 +1073,7 @@ a.test-arrow:hover{
 	padding-top: 1px;
 }
 
-#main > details > .sub-variant > h3 {
+#main .sub-variant > h3 {
 	font-size: 15px;
 	margin-left: 25px;
 	margin-bottom: 5px;

src/librustdoc/markdown.rs

@@ -115,7 +115,7 @@ crate fn render<P: AsRef<Path>>(
 }
 
 /// Runs any tests/code examples in the markdown file `input`.
-crate fn test(mut options: Options) -> Result<(), String> {
+crate fn test(options: Options) -> Result<(), String> {
     let input_str = read_to_string(&options.input)
         .map_err(|err| format!("{}: {}", options.input.display(), err))?;
     let mut opts = TestOptions::default();
@@ -135,14 +135,11 @@ crate fn test(mut options: Options) -> Result<(), String> {
 
     find_testable_code(&input_str, &mut collector, codes, options.enable_per_target_ignores, None);
 
-    options.test_args.insert(0, "rustdoctest".to_string());
-    if options.nocapture {
-        options.test_args.push("--nocapture".to_string());
-    }
-    test::test_main(
-        &options.test_args,
+    crate::doctest::run_tests(
+        options.test_args,
+        options.nocapture,
+        options.display_warnings,
         collector.tests,
-        Some(test::Options::new().display_output(options.display_warnings)),
     );
     Ok(())
 }

src/test/rustdoc/toggle-item-contents.rs

@@ -62,8 +62,7 @@ pub struct PrivStruct {
 }
 
 // @has 'toggle_item_contents/enum.Enum.html'
-// @count - '//details[@class="rustdoc-toggle type-contents-toggle"]' 1
-// @has - '//details[@class="rustdoc-toggle type-contents-toggle"]' 'Show 2 fields'
+// @!has - '//details[@class="rustdoc-toggle type-contents-toggle"]'
 pub enum Enum {
     A, B, C,
     D {
@@ -73,8 +72,7 @@ pub enum Enum {
 }
 
 // @has 'toggle_item_contents/enum.EnumStructVariant.html'
-// @count - '//details[@class="rustdoc-toggle type-contents-toggle"]' 1
-// @has - '//details[@class="rustdoc-toggle type-contents-toggle"]' 'Show 1 field'
+// @!has - '//details[@class="rustdoc-toggle type-contents-toggle"]'
 pub enum EnumStructVariant {
     A, B, C,
     D {

src/test/ui/async-await/issue-86507.rs

@@ -0,0 +1,25 @@
+// edition:2018
+
+use ::core::pin::Pin;
+use ::core::future::Future;
+use ::core::marker::Send;
+
+trait Foo {
+    fn bar<'me, 'async_trait, T: Send>(x: &'me T)
+        -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>
+        where 'me: 'async_trait;
+}
+
+impl Foo for () {
+    fn bar<'me, 'async_trait, T: Send>(x: &'me T)
+        -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>
+        where 'me:'async_trait {
+            Box::pin( //~ ERROR future cannot be sent between threads safely
+                async move {
+                    let x = x;
+                }
+            )
+         }
+}
+
+fn main() { }

src/test/ui/async-await/issue-86507.stderr

@@ -0,0 +1,23 @@
+error: future cannot be sent between threads safely
+  --> $DIR/issue-86507.rs:17:13
+   |
+LL | /             Box::pin(
+LL | |                 async move {
+LL | |                     let x = x;
+LL | |                 }
+LL | |             )
+   | |_____________^ future created by async block is not `Send`
+   |
+note: captured value is not `Send` because `&` references cannot be sent unless their referent is `Sync`
+  --> $DIR/issue-86507.rs:19:29
+   |
+LL |                     let x = x;
+   |                             ^ has type `&T` which is not `Send`, because `T` is not `Sync`
+   = note: required for the cast to the object type `dyn Future<Output = ()> + Send`
+help: consider further restricting type parameter `T`
+   |
+LL |         where 'me:'async_trait, T: std::marker::Sync {
+   |                               ^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+

src/test/ui/bastion-of-the-turbofish.rs

@@ -25,9 +25,12 @@
 //
 // My heart aches in sorrow, for I know I am defeated. Let this be a warning
 // to all those who come after. Here stands the bastion of the Turbofish.
+//
+// RIP Anna Harren, Guardian Angel of the Hallowed Turbofish. <3
 
 // See https://github.com/rust-lang/rust/pull/53562
 // and https://github.com/rust-lang/rfcs/pull/2527
+// and https://twitter.com/garblefart/status/1393236602856611843
 // for context.
 
 fn main() {

src/test/ui/impl-trait/issues/issue-54600.rs

@@ -0,0 +1,7 @@
+use std::fmt::Debug;
+
+fn main() {
+    let x: Option<impl Debug> = Some(44_u32);
+    //~^ `impl Trait` not allowed outside of function and method return types
+    println!("{:?}", x);
+}

src/test/ui/impl-trait/issues/issue-54600.stderr

@@ -0,0 +1,9 @@
+error[E0562]: `impl Trait` not allowed outside of function and method return types
+  --> $DIR/issue-54600.rs:4:19
+   |
+LL |     let x: Option<impl Debug> = Some(44_u32);
+   |                   ^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0562`.

src/test/ui/impl-trait/issues/issue-54840.rs

@@ -0,0 +1,7 @@
+use std::ops::Add;
+
+fn main() {
+    let i: i32 = 0;
+    let j: &impl Add = &i;
+    //~^ `impl Trait` not allowed outside of function and method return types
+}

src/test/ui/impl-trait/issues/issue-54840.stderr

@@ -0,0 +1,9 @@
+error[E0562]: `impl Trait` not allowed outside of function and method return types
+  --> $DIR/issue-54840.rs:5:13
+   |
+LL |     let j: &impl Add = &i;
+   |             ^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0562`.

src/test/ui/impl-trait/issues/issue-58504.rs

@@ -0,0 +1,12 @@
+#![feature(generators, generator_trait, never_type)]
+
+use std::ops::Generator;
+
+fn mk_gen() -> impl Generator<Return=!, Yield=()> {
+    || { loop { yield; } }
+}
+
+fn main() {
+    let gens: [impl Generator<Return=!, Yield=()>;2] = [ mk_gen(), mk_gen() ];
+    //~^ `impl Trait` not allowed outside of function and method return types
+}

src/test/ui/impl-trait/issues/issue-58504.stderr

@@ -0,0 +1,9 @@
+error[E0562]: `impl Trait` not allowed outside of function and method return types
+  --> $DIR/issue-58504.rs:10:16
+   |
+LL |     let gens: [impl Generator<Return=!, Yield=()>;2] = [ mk_gen(), mk_gen() ];
+   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0562`.