moved renamed docs stderr formatted | impl-unused-tps.rs

Author: Kivooeo

tests/ui/impl-unused-tps.rs renamed to tests/ui/traits/constrained-type-params-trait-impl.rs

@@ -1,3 +1,11 @@
+//! Comprehensive test for type parameter constraints in trait implementations
+//!
+//! This tests various scenarios of type parameter usage in trait implementations:
+//! - Properly constrained parameters through trait bounds
+//! - Unconstrained parameters that should cause compilation errors
+//! - Complex constraint scenarios with `where` clauses and associated types
+//! - Conflicting implementations detection
+
 trait Foo<A> {
     fn get(&self, A: &A) {}
 }
@@ -7,34 +15,34 @@ trait Bar {
 }
 
 impl<T> Foo<T> for [isize; 0] {
-    // OK, T is used in `Foo<T>`.
+    // OK: T is used in the trait bound `Foo<T>`
 }
 
 impl<T, U> Foo<T> for [isize; 1] {
     //~^ ERROR the type parameter `U` is not constrained
+    // T is constrained by `Foo<T>`, but U is completely unused
 }
 
 impl<T, U> Foo<T> for [isize; 2]
 where
     T: Bar<Out = U>,
 {
-    // OK, `U` is now constrained by the output type parameter.
+    // OK: T is constrained by `Foo<T>`, U is constrained by the where clause
 }
 
 impl<T: Bar<Out = U>, U> Foo<T> for [isize; 3] {
-    // OK, same as above but written differently.
+    // OK: Same as above but using bound syntax instead of where clause
 }
 
 impl<T, U> Foo<T> for U {
     //~^ ERROR conflicting implementations of trait `Foo<_>` for type `[isize; 0]`
+    // This conflicts with the first impl when U = [isize; 0]
 }
 
 impl<T, U> Bar for T {
     //~^ ERROR the type parameter `U` is not constrained
-
     type Out = U;
-
-    // Using `U` in an associated type within the impl is not good enough!
+    // Using U only in associated type definition is insufficient for constraint
 }
 
 impl<T, U> Bar for T
@@ -43,7 +51,7 @@ where
 {
     //~^^^^ ERROR the type parameter `U` is not constrained by the impl trait, self type, or predicates
     //~| ERROR conflicting implementations of trait `Bar`
-    // This crafty self-referential attempt is still no good.
+    // Self-referential constraint doesn't properly constrain U
 }
 
 impl<T, U, V> Foo<T> for T
@@ -53,17 +61,15 @@ where
     //~^^^^ ERROR the type parameter `U` is not constrained
     //~| ERROR the type parameter `V` is not constrained
     //~| ERROR conflicting implementations of trait `Foo<[isize; 0]>` for type `[isize; 0]`
-
-    // Here, `V` is bound by an output type parameter, but the inputs
-    // are not themselves constrained.
+    // V is bound through output type, but U and V are not properly constrained as inputs
 }
 
 impl<T, U, V> Foo<(T, U)> for T
 where
     (T, U): Bar<Out = V>,
 {
     //~^^^^ ERROR conflicting implementations of trait `Foo<([isize; 0], _)>` for type `[isize; 0]`
-    // As above, but both T and U ARE constrained.
+    // Both T and U are constrained through `Foo<(T, U)>`, but creates conflicting impl
 }
 
 fn main() {}

tests/ui/impl-unused-tps.stderr renamed to tests/ui/traits/constrained-type-params-trait-impl.stderr

@@ -1,5 +1,5 @@
 error[E0119]: conflicting implementations of trait `Foo<_>` for type `[isize; 0]`
-  --> $DIR/impl-unused-tps.rs:28:1
+  --> $DIR/constrained-type-params-trait-impl.rs:37:1
    |
 LL | impl<T> Foo<T> for [isize; 0] {
    | ----------------------------- first implementation here
@@ -8,7 +8,7 @@ LL | impl<T, U> Foo<T> for U {
    | ^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `[isize; 0]`
 
 error[E0119]: conflicting implementations of trait `Foo<[isize; 0]>` for type `[isize; 0]`
-  --> $DIR/impl-unused-tps.rs:49:1
+  --> $DIR/constrained-type-params-trait-impl.rs:57:1
    |
 LL |   impl<T> Foo<T> for [isize; 0] {
    |   ----------------------------- first implementation here
@@ -19,7 +19,7 @@ LL | |     (T, U): Bar<Out = V>,
    | |_________________________^ conflicting implementation for `[isize; 0]`
 
 error[E0119]: conflicting implementations of trait `Foo<([isize; 0], _)>` for type `[isize; 0]`
-  --> $DIR/impl-unused-tps.rs:61:1
+  --> $DIR/constrained-type-params-trait-impl.rs:67:1
    |
 LL |   impl<T> Foo<T> for [isize; 0] {
    |   ----------------------------- first implementation here
@@ -30,37 +30,37 @@ LL | |     (T, U): Bar<Out = V>,
    | |_________________________^ conflicting implementation for `[isize; 0]`
 
 error[E0207]: the type parameter `U` is not constrained by the impl trait, self type, or predicates
-  --> $DIR/impl-unused-tps.rs:13:9
+  --> $DIR/constrained-type-params-trait-impl.rs:21:9
    |
 LL | impl<T, U> Foo<T> for [isize; 1] {
    |         ^ unconstrained type parameter
 
 error[E0207]: the type parameter `U` is not constrained by the impl trait, self type, or predicates
-  --> $DIR/impl-unused-tps.rs:32:9
+  --> $DIR/constrained-type-params-trait-impl.rs:42:9
    |
 LL | impl<T, U> Bar for T {
    |         ^ unconstrained type parameter
 
 error[E0207]: the type parameter `U` is not constrained by the impl trait, self type, or predicates
-  --> $DIR/impl-unused-tps.rs:40:9
+  --> $DIR/constrained-type-params-trait-impl.rs:48:9
    |
 LL | impl<T, U> Bar for T
    |         ^ unconstrained type parameter
 
 error[E0207]: the type parameter `U` is not constrained by the impl trait, self type, or predicates
-  --> $DIR/impl-unused-tps.rs:49:9
+  --> $DIR/constrained-type-params-trait-impl.rs:57:9
    |
 LL | impl<T, U, V> Foo<T> for T
    |         ^ unconstrained type parameter
 
 error[E0207]: the type parameter `V` is not constrained by the impl trait, self type, or predicates
-  --> $DIR/impl-unused-tps.rs:49:12
+  --> $DIR/constrained-type-params-trait-impl.rs:57:12
    |
 LL | impl<T, U, V> Foo<T> for T
    |            ^ unconstrained type parameter
 
 error[E0119]: conflicting implementations of trait `Bar`
-  --> $DIR/impl-unused-tps.rs:40:1
+  --> $DIR/constrained-type-params-trait-impl.rs:48:1
    |
 LL |   impl<T, U> Bar for T {
    |   -------------------- first implementation here