Suggestion moving types before associated types.

This commit extends existing suggestions to move lifetimes before types
in generic arguments to also suggest moving types behind associated type
bindings.

3 files changed, 95 insertions, 0 deletions

diff --git a/src/test/ui/parser/issue-32214.stderr b/src/test/ui/parser/issue-32214.stderr
index a889513eaee..660e517c85a 100644
--- a/src/test/ui/parser/issue-32214.stderr
+++ b/src/test/ui/parser/issue-32214.stderr
@@ -3,6 +3,10 @@ error: type parameters must be declared prior to associated type bindings
    |
 LL | pub fn test<W, I: Trait<Item=(), W> >() {}
    |                                  ^ must be declared prior to associated type bindings
+help: move the type parameter prior to the first associated type binding
+   |
+LL | pub fn test<W, I: Trait<W, Item=()> >() {}
+   |                         ^^       --
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/suggestions/suggest-move-types.rs b/src/test/ui/suggestions/suggest-move-types.rs
new file mode 100644
index 00000000000..8f35e4ecbca
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-move-types.rs
@@ -0,0 +1,42 @@
+#![allow(warnings)]
+
+// This test verifies that the suggestion to move types before associated type bindings
+// is correct.
+
+trait One<T> {
+  type A;
+}
+
+trait Three<T, U, V> {
+  type A;
+  type B;
+  type C;
+}
+
+struct A<T, M: One<A=(), T>> { //~ ERROR type parameters must be declared
+    m: M,
+    t: T,
+}
+
+struct B<T, U, V, M: Three<A=(), B=(), C=(), T, U, V>> { //~ ERROR type parameters must be declared
+    m: M,
+    t: T,
+    u: U,
+    v: V,
+}
+
+struct C<T, U, V, M: Three<T, A=(), B=(), C=(), U, V>> { //~ ERROR type parameters must be declared
+    m: M,
+    t: T,
+    u: U,
+    v: V,
+}
+
+struct D<T, U, V, M: Three<T, A=(), B=(), U, C=(), V>> { //~ ERROR type parameters must be declared
+    m: M,
+    t: T,
+    u: U,
+    v: V,
+}
+
+fn main() {}
diff --git a/src/test/ui/suggestions/suggest-move-types.stderr b/src/test/ui/suggestions/suggest-move-types.stderr
new file mode 100644
index 00000000000..c74f79a00c7
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-move-types.stderr
@@ -0,0 +1,49 @@
+error: type parameters must be declared prior to associated type bindings
+  --> $DIR/suggest-move-types.rs:16:26
+   |
+LL | struct A<T, M: One<A=(), T>> { //~ ERROR type parameters must be declared
+   |                          ^ must be declared prior to associated type bindings
+help: move the type parameter prior to the first associated type binding
+   |
+LL | struct A<T, M: One<T, A=()>> { //~ ERROR type parameters must be declared
+   |                    ^^    --
+
+error: type parameters must be declared prior to associated type bindings
+  --> $DIR/suggest-move-types.rs:21:46
+   |
+LL | struct B<T, U, V, M: Three<A=(), B=(), C=(), T, U, V>> { //~ ERROR type parameters must be declared
+   |                                              ^  ^  ^ must be declared prior to associated type bindings
+   |                                              |  |
+   |                                              |  must be declared prior to associated type bindings
+   |                                              must be declared prior to associated type bindings
+help: move the type parameters prior to the first associated type binding
+   |
+LL | struct B<T, U, V, M: Three<T, U, V, A=(), B=(), C=()>> { //~ ERROR type parameters must be declared
+   |                            ^^ ^^ ^^                --
+
+error: type parameters must be declared prior to associated type bindings
+  --> $DIR/suggest-move-types.rs:28:49
+   |
+LL | struct C<T, U, V, M: Three<T, A=(), B=(), C=(), U, V>> { //~ ERROR type parameters must be declared
+   |                                                 ^  ^ must be declared prior to associated type bindings
+   |                                                 |
+   |                                                 must be declared prior to associated type bindings
+help: move the type parameters prior to the first associated type binding
+   |
+LL | struct C<T, U, V, M: Three<T, U, V, A=(), B=(), C=()>> { //~ ERROR type parameters must be declared
+   |                               ^^ ^^                --
+
+error: type parameters must be declared prior to associated type bindings
+  --> $DIR/suggest-move-types.rs:35:43
+   |
+LL | struct D<T, U, V, M: Three<T, A=(), B=(), U, C=(), V>> { //~ ERROR type parameters must be declared
+   |                                           ^        ^ must be declared prior to associated type bindings
+   |                                           |
+   |                                           must be declared prior to associated type bindings
+help: move the type parameters prior to the first associated type binding
+   |
+LL | struct D<T, U, V, M: Three<T, U, V, A=(), B=(), C=()>> { //~ ERROR type parameters must be declared
+   |                               ^^ ^^          --    --
+
+error: aborting due to 4 previous errors
+