Auto merge of #101990 - clubby789:dont-machine-apply-placeholder-method, r=compiler-errors

Fix auto-application of associated generic functions with placeholders

Fixes #101920

10 files changed, 165 insertions, 15 deletions

diff --git a/src/test/ui/issues/issue-3707.stderr b/src/test/ui/issues/issue-3707.stderr
index 6ca2deee377..07c8101cbc6 100644
--- a/src/test/ui/issues/issue-3707.stderr
+++ b/src/test/ui/issues/issue-3707.stderr
@@ -2,10 +2,10 @@ error[E0599]: no method named `boom` found for reference `&Obj` in the current s
   --> $DIR/issue-3707.rs:10:14
    |
 LL |         self.boom();
-   |         -----^^^^
+   |         -----^^^^--
    |         |    |
    |         |    this is an associated function, not a method
-   |         help: use associated function syntax instead: `Obj::boom`
+   |         help: use associated function syntax instead: `Obj::boom()`
    |
    = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
 note: the candidate is defined in an impl for the type `Obj`
diff --git a/src/test/ui/suggestions/inner_type2.rs b/src/test/ui/suggestions/inner_type2.rs
index c56ea7c030d..fac68c053eb 100644
--- a/src/test/ui/suggestions/inner_type2.rs
+++ b/src/test/ui/suggestions/inner_type2.rs
@@ -22,5 +22,5 @@ fn main() {
     let item = std::mem::MaybeUninit::new(Struct { p: 42_u32 });
     item.method();
     //~^ ERROR no method named `method` found for union `MaybeUninit` in the current scope [E0599]
-    //~| HELP if this `MaybeUninit::<Struct<u32>>` has been initialized, use one of the `assume_init` methods to access the inner value
+    //~| HELP if this `MaybeUninit<Struct<u32>>` has been initialized, use one of the `assume_init` methods to access the inner value
 }
diff --git a/src/test/ui/suggestions/inner_type2.stderr b/src/test/ui/suggestions/inner_type2.stderr
index eddfd9d6340..984366123c8 100644
--- a/src/test/ui/suggestions/inner_type2.stderr
+++ b/src/test/ui/suggestions/inner_type2.stderr
@@ -17,7 +17,7 @@ error[E0599]: no method named `method` found for union `MaybeUninit` in the curr
 LL |     item.method();
    |          ^^^^^^ method not found in `MaybeUninit<Struct<u32>>`
    |
-   = help: if this `MaybeUninit::<Struct<u32>>` has been initialized, use one of the `assume_init` methods to access the inner value
+   = help: if this `MaybeUninit<Struct<u32>>` has been initialized, use one of the `assume_init` methods to access the inner value
 note: the method `method` exists on the type `Struct<u32>`
   --> $DIR/inner_type2.rs:6:5
    |
diff --git a/src/test/ui/suggestions/issue-102354.stderr b/src/test/ui/suggestions/issue-102354.stderr
index 4f76c5f2e75..b17c4dc5dfb 100644
--- a/src/test/ui/suggestions/issue-102354.stderr
+++ b/src/test/ui/suggestions/issue-102354.stderr
@@ -13,7 +13,7 @@ LL |     fn func() {}
 help: use associated function syntax instead
    |
 LL |     i32::func();
-   |     ~~~~~~~~~
+   |     ~~~~~~~~~~~
 help: disambiguate the associated function for the candidate
    |
 LL |     <i32 as Trait>::func(x);
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.rs b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.rs
new file mode 100644
index 00000000000..a39b8711dd8
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.rs
@@ -0,0 +1,11 @@
+struct GenericAssocMethod<T>(T);
+
+impl<T> GenericAssocMethod<T> {
+    fn default_hello() {}
+}
+
+fn main() {
+    let x = GenericAssocMethod(33);
+    x.default_hello();
+    //~^ ERROR no method named `default_hello` found
+}
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.stderr b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.stderr
new file mode 100644
index 00000000000..c247e73b39c
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.stderr
@@ -0,0 +1,22 @@
+error[E0599]: no method named `default_hello` found for struct `GenericAssocMethod<{integer}>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish-placeholder.rs:9:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `default_hello` not found for this struct
+...
+LL |     x.default_hello();
+   |     --^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<_>::default_hello()`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish-placeholder.rs:4:5
+   |
+LL |     fn default_hello() {}
+   |     ^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-through-deref.stderr b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-through-deref.stderr
index 996d5773118..7c9f0b6c212 100644
--- a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-through-deref.stderr
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-through-deref.stderr
@@ -2,10 +2,10 @@ error[E0599]: no method named `hello` found for struct `RefMut<'_, HasAssocMetho
   --> $DIR/suggest-assoc-fn-call-with-turbofish-through-deref.rs:11:11
    |
 LL |     state.hello();
-   |     ------^^^^^
+   |     ------^^^^^--
    |     |     |
    |     |     this is an associated function, not a method
-   |     help: use associated function syntax instead: `HasAssocMethod::hello`
+   |     help: use associated function syntax instead: `HasAssocMethod::hello()`
    |
    = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
 note: the candidate is defined in an impl for the type `HasAssocMethod`
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.fixed b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.fixed
new file mode 100644
index 00000000000..02dd0715c80
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.fixed
@@ -0,0 +1,26 @@
+// run-rustfix
+
+struct GenericAssocMethod<T>(T);
+
+impl<T> GenericAssocMethod<T> {
+    fn default_hello() {}
+    fn self_ty_hello(_: Self) {}
+    fn self_ty_ref_hello(_: &Self) {}
+}
+
+fn main() {
+    // Test for inferred types
+    let x = GenericAssocMethod(33);
+    GenericAssocMethod::<_>::self_ty_ref_hello(&x);
+    //~^ ERROR no method named `self_ty_ref_hello` found
+    GenericAssocMethod::<_>::self_ty_hello(x);
+    //~^ ERROR no method named `self_ty_hello` found
+    // Test for known types
+    let y = GenericAssocMethod(33i32);
+    GenericAssocMethod::<i32>::default_hello();
+    //~^ ERROR no method named `default_hello` found
+    GenericAssocMethod::<i32>::self_ty_ref_hello(&y);
+    //~^ ERROR no method named `self_ty_ref_hello` found
+    GenericAssocMethod::<i32>::self_ty_hello(y);
+    //~^ ERROR no method named `self_ty_hello` found
+}
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.rs b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.rs
index 2a829db5383..1d0ca8e780a 100644
--- a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.rs
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.rs
@@ -1,11 +1,26 @@
+// run-rustfix
+
 struct GenericAssocMethod<T>(T);
 
 impl<T> GenericAssocMethod<T> {
     fn default_hello() {}
+    fn self_ty_hello(_: Self) {}
+    fn self_ty_ref_hello(_: &Self) {}
 }
 
 fn main() {
-    let x = GenericAssocMethod(33i32);
-    x.default_hello();
+    // Test for inferred types
+    let x = GenericAssocMethod(33);
+    x.self_ty_ref_hello();
+    //~^ ERROR no method named `self_ty_ref_hello` found
+    x.self_ty_hello();
+    //~^ ERROR no method named `self_ty_hello` found
+    // Test for known types
+    let y = GenericAssocMethod(33i32);
+    y.default_hello();
     //~^ ERROR no method named `default_hello` found
+    y.self_ty_ref_hello();
+    //~^ ERROR no method named `self_ty_ref_hello` found
+    y.self_ty_hello();
+    //~^ ERROR no method named `self_ty_hello` found
 }
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.stderr b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.stderr
index 3fb418b1c0a..92b03fc7714 100644
--- a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.stderr
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.stderr
@@ -1,22 +1,98 @@
+error[E0599]: no method named `self_ty_ref_hello` found for struct `GenericAssocMethod<{integer}>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:14:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `self_ty_ref_hello` not found for this struct
+...
+LL |     x.self_ty_ref_hello();
+   |     --^^^^^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<_>::self_ty_ref_hello(&x)`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:8:5
+   |
+LL |     fn self_ty_ref_hello(_: &Self) {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0599]: no method named `self_ty_hello` found for struct `GenericAssocMethod<{integer}>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:16:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `self_ty_hello` not found for this struct
+...
+LL |     x.self_ty_hello();
+   |     --^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<_>::self_ty_hello(x)`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:7:5
+   |
+LL |     fn self_ty_hello(_: Self) {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
 error[E0599]: no method named `default_hello` found for struct `GenericAssocMethod<i32>` in the current scope
-  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:9:7
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:20:7
    |
 LL | struct GenericAssocMethod<T>(T);
    | ---------------------------- method `default_hello` not found for this struct
 ...
-LL |     x.default_hello();
-   |     --^^^^^^^^^^^^^
+LL |     y.default_hello();
+   |     --^^^^^^^^^^^^^--
    |     | |
    |     | this is an associated function, not a method
-   |     help: use associated function syntax instead: `GenericAssocMethod::<i32>::default_hello`
+   |     help: use associated function syntax instead: `GenericAssocMethod::<i32>::default_hello()`
    |
    = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
 note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
-  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:4:5
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:6:5
    |
 LL |     fn default_hello() {}
    |     ^^^^^^^^^^^^^^^^^^
 
-error: aborting due to previous error
+error[E0599]: no method named `self_ty_ref_hello` found for struct `GenericAssocMethod<i32>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:22:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `self_ty_ref_hello` not found for this struct
+...
+LL |     y.self_ty_ref_hello();
+   |     --^^^^^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<i32>::self_ty_ref_hello(&y)`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:8:5
+   |
+LL |     fn self_ty_ref_hello(_: &Self) {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0599]: no method named `self_ty_hello` found for struct `GenericAssocMethod<i32>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:24:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `self_ty_hello` not found for this struct
+...
+LL |     y.self_ty_hello();
+   |     --^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<i32>::self_ty_hello(y)`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:7:5
+   |
+LL |     fn self_ty_hello(_: Self) {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 5 previous errors
 
 For more information about this error, try `rustc --explain E0599`.