Handle inherent associated types fallout

Author: fmease

tests/rustdoc-json/type/inherent_associated_type_bound.rs

@@ -5,14 +5,15 @@
 // @set Carrier = '$.index[*][?(@.name=="Carrier")].id'
 pub struct Carrier<'a>(&'a ());
 
-// @is '$.index[*][?(@.name=="User")].inner.typedef.type.function_pointer.generic_params[*].name' \""'b"\"
-// @is '$.index[*][?(@.name=="User")].inner.typedef.type.function_pointer.decl.inputs[0][1].qualified_path.self_type.resolved_path.id' $Carrier
-// @is '$.index[*][?(@.name=="User")].inner.typedef.type.function_pointer.decl.inputs[0][1].qualified_path.self_type.resolved_path.args.angle_bracketed.args[0].lifetime' \""'b"\"
-// @is '$.index[*][?(@.name=="User")].inner.typedef.type.function_pointer.decl.inputs[0][1].qualified_path.name' '"Focus"'
-// @is '$.index[*][?(@.name=="User")].inner.typedef.type.function_pointer.decl.inputs[0][1].qualified_path.trait' null
-// @is '$.index[*][?(@.name=="User")].inner.typedef.type.function_pointer.decl.inputs[0][1].qualified_path.args.angle_bracketed.args[0].type.primitive' '"i32"'
-
-pub type User = for<'b> fn(Carrier<'b>::Focus<i32>);
+// @count "$.index[*][?(@.name=='user')].inner.function.decl.inputs[*]" 1
+// @is "$.index[*][?(@.name=='user')].inner.function.decl.inputs[0][0]" '"_"'
+// @is '$.index[*][?(@.name=="user")].inner.function.decl.inputs[0][1].function_pointer.generic_params[*].name' \""'b"\"
+// @is '$.index[*][?(@.name=="user")].inner.function.decl.inputs[0][1].function_pointer.decl.inputs[0][1].qualified_path.self_type.resolved_path.id' $Carrier
+// @is '$.index[*][?(@.name=="user")].inner.function.decl.inputs[0][1].function_pointer.decl.inputs[0][1].qualified_path.self_type.resolved_path.args.angle_bracketed.args[0].lifetime' \""'b"\"
+// @is '$.index[*][?(@.name=="user")].inner.function.decl.inputs[0][1].function_pointer.decl.inputs[0][1].qualified_path.name' '"Focus"'
+// @is '$.index[*][?(@.name=="user")].inner.function.decl.inputs[0][1].function_pointer.decl.inputs[0][1].qualified_path.trait' null
+// @is '$.index[*][?(@.name=="user")].inner.function.decl.inputs[0][1].function_pointer.decl.inputs[0][1].qualified_path.args.angle_bracketed.args[0].type.primitive' '"i32"'
+pub fn user(_: for<'b> fn(Carrier<'b>::Focus<i32>)) {}
 
 impl<'a> Carrier<'a> {
     pub type Focus<T> = &'a mut T;

tests/rustdoc-json/type/inherent_associated_type_projections.rs

@@ -5,11 +5,13 @@
 // @set Parametrized = '$.index[*][?(@.name=="Parametrized")].id'
 pub struct Parametrized<T>(T);
 
-// @is '$.index[*][?(@.name=="Test")].inner.typedef.type.qualified_path.self_type.resolved_path.id' $Parametrized
-// @is '$.index[*][?(@.name=="Test")].inner.typedef.type.qualified_path.self_type.resolved_path.args.angle_bracketed.args[0].type.primitive' \"i32\"
-// @is '$.index[*][?(@.name=="Test")].inner.typedef.type.qualified_path.name' '"Proj"'
-// @is '$.index[*][?(@.name=="Test")].inner.typedef.type.qualified_path.trait' null
-pub type Test = Parametrized<i32>::Proj;
+// @count "$.index[*][?(@.name=='test')].inner.function.decl.inputs[*]" 1
+// @is "$.index[*][?(@.name=='test')].inner.function.decl.inputs[0][0]" '"_"'
+// @is '$.index[*][?(@.name=="test")].inner.function.decl.inputs[0][1].qualified_path.self_type.resolved_path.id' $Parametrized
+// @is '$.index[*][?(@.name=="test")].inner.function.decl.inputs[0][1].qualified_path.self_type.resolved_path.args.angle_bracketed.args[0].type.primitive' \"i32\"
+// @is '$.index[*][?(@.name=="test")].inner.function.decl.inputs[0][1].qualified_path.name' '"Proj"'
+// @is '$.index[*][?(@.name=="test")].inner.function.decl.inputs[0][1].qualified_path.trait' null
+pub fn test(_: Parametrized<i32>::Proj) {}
 
 /// param_bool
 impl Parametrized<bool> {

tests/rustdoc/inherent-projections.rs

@@ -13,8 +13,8 @@ impl Owner {
 }
 
 // Make sure we handle bound vars correctly.
-// @has 'inherent_projections/type.User.html' '//pre[@class="rust item-decl"]' "for<'a> fn(_: Carrier<'a>::Focus)"
-pub type User = for<'a> fn(Carrier<'a>::Focus);
+// @has 'inherent_projections/fn.user.html' '//pre[@class="rust item-decl"]' "user(_: for<'a> fn(_: Carrier<'a>::Focus))"
+pub fn user(_: for<'a> fn(Carrier<'a>::Focus)) {}
 
 pub struct Carrier<'a>(&'a ());
 
@@ -27,11 +27,11 @@ impl<'a> Carrier<'a> {
 // FIXME(inherent_associated_types): Below we link to `Proj` but we should link to `Proj-1`.
 // The current test checks for the buggy behavior for demonstration purposes.
 
-// @has 'inherent_projections/type.Test.html'
-// @has - '//pre[@class="rust item-decl"]' "Parametrized<i32>"
+// @has 'inherent_projections/fn.test.html'
+// @has - '//pre[@class="rust item-decl"]' "test(_: Parametrized<i32>::Proj)"
 // @has - '//pre[@class="rust item-decl"]//a[@class="associatedtype"]/@href' 'struct.Parametrized.html#associatedtype.Proj'
 // @!has - '//pre[@class="rust item-decl"]//a[@class="associatedtype"]/@href' 'struct.Parametrized.html#associatedtype.Proj-1'
-pub type Test = Parametrized<i32>::Proj;
+pub fn test(_: Parametrized<i32>::Proj) {}
 
 pub struct Parametrized<T>(T);
 

tests/ui/associated-inherent-types/issue-111879-0.rs

@@ -5,10 +5,8 @@
 
 pub struct Carrier<'a>(&'a ());
 
-pub type User = for<'b> fn(Carrier<'b>::Focus<i32>);
-
 impl<'a> Carrier<'a> {
-    pub type Focus<T> = &'a mut User; //~ ERROR overflow evaluating associated type
+    pub type Focus<T> = &'a mut for<'b> fn(Carrier<'b>::Focus<i32>); //~ ERROR overflow evaluating associated type
 }
 
 fn main() {}

tests/ui/associated-inherent-types/issue-111879-0.stderr

@@ -1,8 +1,8 @@
 error: overflow evaluating associated type `Carrier<'b>::Focus<i32>`
-  --> $DIR/issue-111879-0.rs:11:25
+  --> $DIR/issue-111879-0.rs:9:25
    |
-LL |     pub type Focus<T> = &'a mut User;
-   |                         ^^^^^^^^^^^^
+LL |     pub type Focus<T> = &'a mut for<'b> fn(Carrier<'b>::Focus<i32>);
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 

tests/ui/associated-inherent-types/late-bound-regions.rs

@@ -3,8 +3,6 @@
 
 // Test if we correctly normalize `S<'a>::P` with respect to late-bound regions.
 
-type Function = for<'a> fn(&'a i32) -> S<'a>::P;
-
 struct S<'a>(&'a ());
 
 trait Inter {
@@ -16,7 +14,7 @@ impl<'a> S<'a> {
 }
 
 fn ret_ref_local<'e>() -> &'e i32 {
-    let f: Function = |x| x;
+    let f: for<'a> fn(&'a i32) -> S<'a>::P = |x| x;
 
     let local = 0;
     f(&local) //~ ERROR cannot return value referencing local variable `local`

tests/ui/associated-inherent-types/late-bound-regions.stderr

@@ -1,5 +1,5 @@
 error[E0515]: cannot return value referencing local variable `local`
-  --> $DIR/late-bound-regions.rs:22:5
+  --> $DIR/late-bound-regions.rs:20:5
    |
 LL |     f(&local)
    |     ^^------^

tests/ui/associated-inherent-types/not-found-self-type-differs.alias.stderr

@@ -1,5 +1,3 @@
-// revisions: local alias
-
 #![feature(inherent_associated_types)]
 #![allow(incomplete_features)]
 
@@ -13,10 +11,7 @@ impl<T> Family<Result<T, ()>> {
     type Proj = Self;
 }
 
-#[cfg(alias)]
-type Alias = Family<Option<()>>::Proj; //[alias]~ ERROR associated type `Proj` not found for `Family<Option<()>>`
-
 fn main() {
-    #[cfg(local)]
-    let _: Family<std::path::PathBuf>::Proj = (); //[local]~ ERROR associated type `Proj` not found for `Family<PathBuf>`
+    let _: Family<Option<()>>::Proj; //~ ERROR associated type `Proj` not found for `Family<Option<()>>`
+    let _: Family<std::path::PathBuf>::Proj = (); //~ ERROR associated type `Proj` not found for `Family<PathBuf>`
 }

tests/ui/associated-inherent-types/not-found-self-type-differs.local.stderr

@@ -0,0 +1,29 @@
+error[E0220]: associated type `Proj` not found for `Family<Option<()>>` in the current scope
+  --> $DIR/not-found-self-type-differs.rs:15:32
+   |
+LL | struct Family<T>(T);
+   | ---------------- associated item `Proj` not found for this struct
+...
+LL |     let _: Family<Option<()>>::Proj;
+   |                                ^^^^ associated item not found in `Family<Option<()>>`
+   |
+   = note: the associated type was found for
+           - `Family<()>`
+           - `Family<Result<T, ()>>`
+
+error[E0220]: associated type `Proj` not found for `Family<PathBuf>` in the current scope
+  --> $DIR/not-found-self-type-differs.rs:16:40
+   |
+LL | struct Family<T>(T);
+   | ---------------- associated item `Proj` not found for this struct
+...
+LL |     let _: Family<std::path::PathBuf>::Proj = ();
+   |                                        ^^^^ associated item not found in `Family<PathBuf>`
+   |
+   = note: the associated type was found for
+           - `Family<()>`
+           - `Family<Result<T, ()>>`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0220`.

tests/ui/associated-inherent-types/not-found-self-type-differs.rs

@@ -17,7 +17,7 @@ impl<T, S> Subj<(T, S)> {
 }
 
 fn main() {
-    type A = S<()>::P;
+    let _: S<()>::P;
 
     let _: Subj<(i32, i32)>::Un = 0i32; //~ ERROR mismatched types
 }

tests/ui/associated-inherent-types/not-found-self-type-differs.stderr

@@ -15,8 +15,7 @@ impl<T> S<(T,)> {
 
 fn main() {
     // Regression test for issue #104240.
-    type A = S<()>::P;
-    let _: A = ();
+    let _: S<()>::P = ();
 
     // Regression test for issue #107468.
     let _: S<(i32,)>::Un = 0i32;

tests/ui/associated-inherent-types/substitute-params-bad.rs

@@ -1,4 +1,5 @@
-// check-pass
+// FIXME(inherent_associated_types): This should be `check-pass`
+// known-bug: #108491
 // compile-flags: --crate-type=lib
 
 #![feature(inherent_associated_types)]
@@ -17,7 +18,6 @@
 
 pub type Alias<T: Bound> = (Source<T>::Assoc,);
 
-
 pub struct Source<T>(T);
 pub trait Bound {}
 

tests/ui/associated-inherent-types/substitute-params.rs

@@ -0,0 +1,55 @@
+error[E0391]: cycle detected when expanding type alias `Alias`
+  --> $DIR/type-alias-bounds-are-enforced.rs:19:1
+   |
+LL | pub type Alias<T: Bound> = (Source<T>::Assoc,);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: ...which requires computing the variances of `Source`...
+  --> $DIR/type-alias-bounds-are-enforced.rs:21:1
+   |
+LL | pub struct Source<T>(T);
+   | ^^^^^^^^^^^^^^^^^^^^
+   = note: ...which requires computing the variances for items in this crate...
+   = note: ...which again requires expanding type alias `Alias`, completing the cycle
+note: cycle used when collecting item types in top-level module
+  --> $DIR/type-alias-bounds-are-enforced.rs:5:1
+   |
+LL | / #![feature(inherent_associated_types)]
+LL | | #![allow(incomplete_features)]
+LL | |
+LL | | // Bounds on the self type play a major role in the resolution of inherent associated types (*).
+...  |
+LL | |     pub type Assoc = ();
+LL | | }
+   | |_^
+   = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
+
+error[E0391]: cycle detected when expanding type alias `Alias`
+  --> $DIR/type-alias-bounds-are-enforced.rs:19:1
+   |
+LL | pub type Alias<T: Bound> = (Source<T>::Assoc,);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: ...which requires computing the variances of `Source`...
+  --> $DIR/type-alias-bounds-are-enforced.rs:21:1
+   |
+LL | pub struct Source<T>(T);
+   | ^^^^^^^^^^^^^^^^^^^^
+   = note: ...which requires computing the variances for items in this crate...
+   = note: ...which again requires expanding type alias `Alias`, completing the cycle
+note: cycle used when collecting item types in top-level module
+  --> $DIR/type-alias-bounds-are-enforced.rs:5:1
+   |
+LL | / #![feature(inherent_associated_types)]
+LL | | #![allow(incomplete_features)]
+LL | |
+LL | | // Bounds on the self type play a major role in the resolution of inherent associated types (*).
+...  |
+LL | |     pub type Assoc = ();
+LL | | }
+   | |_^
+   = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0391`.