Rollup merge of #73320 - estebank:type-param-sugg-more, r=davidtwco

Make new type param suggestion more targetted

Do not suggest new type param when encountering a missing type in an ADT
field with generic parameters.

Fix #72640.

src/test/ui/associated-types/associated-types-eq-1.stderr

@@ -4,7 +4,16 @@ error[E0412]: cannot find type `A` in this scope
 LL | fn foo2<I: Foo>(x: I) {
    |         - similarly named type parameter `I` defined here
 LL |     let _: A = x.boo();
-   |            ^ help: a type parameter with a similar name exists: `I`
+   |            ^
+   |
+help: a type parameter with a similar name exists
+   |
+LL |     let _: I = x.boo();
+   |            ^
+help: you might be missing a type parameter
+   |
+LL | fn foo2<I: Foo, A>(x: I) {
+   |               ^^^
 
 error: aborting due to previous error
 

src/test/ui/suggestions/type-not-found-in-adt-field.rs

@@ -0,0 +1,9 @@
+struct Struct {
+    m: Vec<Someunknownname<String, ()>>, //~ ERROR cannot find type `Someunknownname` in this scope
+    //~^ NOTE not found in this scope
+}
+struct OtherStruct { //~ HELP you might be missing a type parameter
+    m: K, //~ ERROR cannot find type `K` in this scope
+    //~^ NOTE not found in this scope
+}
+fn main() {}

src/test/ui/suggestions/type-not-found-in-adt-field.stderr

@@ -0,0 +1,17 @@
+error[E0412]: cannot find type `Someunknownname` in this scope
+  --> $DIR/type-not-found-in-adt-field.rs:2:12
+   |
+LL |     m: Vec<Someunknownname<String, ()>>,
+   |            ^^^^^^^^^^^^^^^ not found in this scope
+
+error[E0412]: cannot find type `K` in this scope
+  --> $DIR/type-not-found-in-adt-field.rs:6:8
+   |
+LL | struct OtherStruct {
+   |                   - help: you might be missing a type parameter: `<K>`
+LL |     m: K,
+   |        ^ not found in this scope
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0412`.