Auto merge of #77741 - JohnTitor:add-tests, r=matthewjasper

Add some regression tests

They're fixed since nightly-2020-10-07:
Closes #52843
Closes #53448
Closes #54108
Closes #65581
Closes #65934
Closes #70292
Closes #71443

Author: bors

Diff for: compiler/rustc_typeck/src/bounds.rs

@@ -72,7 +72,7 @@ impl<'tcx> Bounds<'tcx> {
                     .iter()
                     .map(|&(region_bound, span)| {
                         let outlives = ty::OutlivesPredicate(param_ty, region_bound);
-                        (ty::Binder::dummy(outlives).to_predicate(tcx), span)
+                        (ty::Binder::bind(outlives).to_predicate(tcx), span)
                     })
                     .chain(self.trait_bounds.iter().map(|&(bound_trait_ref, span, constness)| {
                         let predicate = bound_trait_ref.with_constness(constness).to_predicate(tcx);

Diff for: src/test/ui/associated-type-bounds/issue-70292.rs

@@ -0,0 +1,21 @@
+// check-pass
+
+#![feature(associated_type_bounds)]
+
+fn foo<F>(_: F)
+where
+    F: for<'a> Trait<Output: 'a>,
+{
+}
+
+trait Trait {
+    type Output;
+}
+
+impl<T> Trait for T {
+    type Output = ();
+}
+
+fn main() {
+    foo(());
+}

Diff for: src/test/ui/associated-type-bounds/issue-71443-1.rs

@@ -0,0 +1,9 @@
+#![feature(associated_type_bounds)]
+
+struct Incorrect;
+
+fn hello<F: for<'a> Iterator<Item: 'a>>() {
+    Incorrect //~ERROR: mismatched types
+}
+
+fn main() {}

Diff for: src/test/ui/associated-type-bounds/issue-71443-1.stderr

@@ -0,0 +1,11 @@
+error[E0308]: mismatched types
+  --> $DIR/issue-71443-1.rs:6:5
+   |
+LL | fn hello<F: for<'a> Iterator<Item: 'a>>() {
+   |                                           - help: try adding a return type: `-> Incorrect`
+LL |     Incorrect
+   |     ^^^^^^^^^ expected `()`, found struct `Incorrect`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.

Diff for: src/test/ui/associated-type-bounds/issue-71443-2.rs

@@ -0,0 +1,11 @@
+// check-pass
+
+#![feature(associated_type_bounds)]
+
+fn hello<'b, F>()
+where
+    for<'a> F: Iterator<Item: 'a> + 'b,
+{
+}
+
+fn main() {}

Diff for: src/test/ui/associated-types/issue-54108.rs

@@ -0,0 +1,41 @@
+use std::ops::Add;
+
+pub trait Encoder {
+    type Size: Add<Output = Self::Size>;
+
+    fn foo(&self) -> Self::Size;
+}
+
+pub trait SubEncoder: Encoder {
+    type ActualSize;
+
+    fn bar(&self) -> Self::Size;
+}
+
+impl<T> Encoder for T
+where
+    T: SubEncoder,
+{
+    type Size = <Self as SubEncoder>::ActualSize;
+    //~^ ERROR: cannot add `<T as SubEncoder>::ActualSize` to `<T as SubEncoder>::ActualSize`
+
+    fn foo(&self) -> Self::Size {
+        self.bar() + self.bar()
+    }
+}
+
+pub struct UnitEncoder;
+
+impl SubEncoder for UnitEncoder {
+    type ActualSize = ();
+
+    fn bar(&self) {}
+}
+
+pub fn fun<R: Encoder>(encoder: &R) {
+    encoder.foo();
+}
+
+fn main() {
+    fun(&UnitEncoder {});
+}

Diff for: src/test/ui/associated-types/issue-54108.stderr

@@ -0,0 +1,18 @@
+error[E0277]: cannot add `<T as SubEncoder>::ActualSize` to `<T as SubEncoder>::ActualSize`
+  --> $DIR/issue-54108.rs:19:5
+   |
+LL |     type Size: Add<Output = Self::Size>;
+   |                ------------------------ required by this bound in `Encoder::Size`
+...
+LL |     type Size = <Self as SubEncoder>::ActualSize;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ no implementation for `<T as SubEncoder>::ActualSize + <T as SubEncoder>::ActualSize`
+   |
+   = help: the trait `Add` is not implemented for `<T as SubEncoder>::ActualSize`
+help: consider further restricting the associated type
+   |
+LL |     T: SubEncoder, <T as SubEncoder>::ActualSize: Add
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.

Diff for: src/test/ui/associated-types/issue-65934.rs

@@ -0,0 +1,17 @@
+// check-pass
+
+trait Trait {
+    type Assoc;
+}
+
+impl Trait for () {
+    type Assoc = ();
+}
+
+fn unit() -> impl Into<<() as Trait>::Assoc> {}
+
+pub fn ice() {
+    Into::into(unit());
+}
+
+fn main() {}

Diff for: src/test/ui/impl-trait/issues/issue-65581.rs

@@ -0,0 +1,33 @@
+// check-pass
+
+#![allow(dead_code)]
+
+trait Trait1<T, U> {
+    fn f1(self) -> U;
+}
+
+trait Trait2 {
+    type T;
+    type U: Trait2<T = Self::T>;
+    fn f2(f: impl FnOnce(&Self::U));
+}
+
+fn f3<T: Trait2>() -> impl Trait1<T, T::T> {
+    Struct1
+}
+
+struct Struct1;
+
+impl<T: Trait2> Trait1<T, T::T> for Struct1 {
+    fn f1(self) -> T::T {
+        unimplemented!()
+    }
+}
+
+fn f4<T: Trait2>() {
+    T::f2(|_| {
+        f3::<T::U>().f1();
+    });
+}
+
+fn main() {}

Diff for: src/test/ui/type-alias-impl-trait/issue-52843.rs

@@ -0,0 +1,15 @@
+#![feature(type_alias_impl_trait)]
+
+type Foo<T> = impl Default;
+//~^ ERROR: the trait bound `T: Default` is not satisfied
+
+#[allow(unused)]
+fn foo<T: Default>(t: T) -> Foo<T> {
+    t
+}
+
+struct NotDefault;
+
+fn main() {
+    let _ = Foo::<NotDefault>::default();
+}

Diff for: src/test/ui/type-alias-impl-trait/issue-52843.stderr

@@ -0,0 +1,14 @@
+error[E0277]: the trait bound `T: Default` is not satisfied
+  --> $DIR/issue-52843.rs:3:15
+   |
+LL | type Foo<T> = impl Default;
+   |               ^^^^^^^^^^^^ the trait `Default` is not implemented for `T`
+   |
+help: consider restricting type parameter `T`
+   |
+LL | type Foo<T: Default> = impl Default;
+   |           ^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.

Diff for: src/test/ui/unboxed-closures/issue-53448.rs

@@ -0,0 +1,15 @@
+#![feature(unboxed_closures)]
+
+trait Lt<'a> {
+    type T;
+}
+impl<'a> Lt<'a> for () {
+    type T = ();
+}
+
+fn main() {
+    let v: <() as Lt<'_>>::T = ();
+    let f: &mut dyn FnMut<(_,), Output = ()> = &mut |_: <() as Lt<'_>>::T| {};
+    //~^ ERROR: the size for values of type `<() as Lt<'_>>::T` cannot be known
+    f(v);
+}

Diff for: src/test/ui/unboxed-closures/issue-53448.stderr

@@ -0,0 +1,20 @@
+error[E0277]: the size for values of type `<() as Lt<'_>>::T` cannot be known at compilation time
+  --> $DIR/issue-53448.rs:12:54
+   |
+LL |     let f: &mut dyn FnMut<(_,), Output = ()> = &mut |_: <() as Lt<'_>>::T| {};
+   |                                                      ^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `<() as Lt<'_>>::T`
+   = help: unsized locals are gated as an unstable feature
+help: consider further restricting the associated type
+   |
+LL | fn main() where <() as Lt<'_>>::T: Sized {
+   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: function arguments must have a statically known size, borrowed types always have a known size
+   |
+LL |     let f: &mut dyn FnMut<(_,), Output = ()> = &mut |_: &<() as Lt<'_>>::T| {};
+   |                                                         ^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.