Ensure Copy exception in trait definition for `wrong_self_conventio…

tests/ui/wrong_self_convention.rs

@@ -94,7 +94,8 @@ mod issue6307 {
     trait T: Sized {
         fn as_i32(self) {}
         fn as_u32(&self) {}
-        fn into_i32(&self) {}
+        fn into_i32(self) {}
+        fn into_i32_ref(&self) {}
         fn into_u32(self) {}
         fn is_i32(self) {}
         fn is_u32(&self) {}
@@ -117,7 +118,32 @@ mod issue6307 {
     trait U {
         fn as_i32(self);
         fn as_u32(&self);
-        fn into_i32(&self);
+        fn into_i32(self);
+        fn into_i32_ref(&self);
+        fn into_u32(self);
+        fn is_i32(self);
+        fn is_u32(&self);
+        fn to_i32(self);
+        fn to_u32(&self);
+        fn from_i32(self);
+        // check whether the lint can be allowed at the function level
+        #[allow(clippy::wrong_self_convention)]
+        fn from_cake(self);
+
+        // test for false positives
+        fn as_(self);
+        fn into_(&self);
+        fn is_(self);
+        fn to_(self);
+        fn from_(self);
+        fn to_mut(&mut self);
+    }
+
+    trait C: Copy {
+        fn as_i32(self);
+        fn as_u32(&self);
+        fn into_i32(self);
+        fn into_i32_ref(&self);
         fn into_u32(self);
         fn is_i32(self);
         fn is_u32(&self);

tests/ui/wrong_self_convention.stderr

@@ -79,58 +79,70 @@ LL |         fn as_i32(self) {}
    |                   ^^^^
 
 error: methods called `into_*` usually take self by value; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:97:21
+  --> $DIR/wrong_self_convention.rs:98:25
    |
-LL |         fn into_i32(&self) {}
-   |                     ^^^^^
+LL |         fn into_i32_ref(&self) {}
+   |                         ^^^^^
 
 error: methods called `is_*` usually take self by reference or no self; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:99:19
+  --> $DIR/wrong_self_convention.rs:100:19
    |
 LL |         fn is_i32(self) {}
    |                   ^^^^
 
 error: methods called `to_*` usually take self by reference; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:101:19
+  --> $DIR/wrong_self_convention.rs:102:19
    |
 LL |         fn to_i32(self) {}
    |                   ^^^^
 
 error: methods called `from_*` usually take no self; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:103:21
+  --> $DIR/wrong_self_convention.rs:104:21
    |
 LL |         fn from_i32(self) {}
    |                     ^^^^
 
 error: methods called `as_*` usually take self by reference or self by mutable reference; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:118:19
+  --> $DIR/wrong_self_convention.rs:119:19
    |
 LL |         fn as_i32(self);
    |                   ^^^^
 
 error: methods called `into_*` usually take self by value; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:120:21
+  --> $DIR/wrong_self_convention.rs:122:25
    |
-LL |         fn into_i32(&self);
-   |                     ^^^^^
+LL |         fn into_i32_ref(&self);
+   |                         ^^^^^
 
 error: methods called `is_*` usually take self by reference or no self; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:122:19
+  --> $DIR/wrong_self_convention.rs:124:19
    |
 LL |         fn is_i32(self);
    |                   ^^^^
 
 error: methods called `to_*` usually take self by reference; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:124:19
+  --> $DIR/wrong_self_convention.rs:126:19
    |
 LL |         fn to_i32(self);
    |                   ^^^^
 
 error: methods called `from_*` usually take no self; consider choosing a less ambiguous name
-  --> $DIR/wrong_self_convention.rs:126:21
+  --> $DIR/wrong_self_convention.rs:128:21
+   |
+LL |         fn from_i32(self);
+   |                     ^^^^
+
+error: methods called `into_*` usually take self by value; consider choosing a less ambiguous name
+  --> $DIR/wrong_self_convention.rs:146:25
+   |
+LL |         fn into_i32_ref(&self);
+   |                         ^^^^^
+
+error: methods called `from_*` usually take no self; consider choosing a less ambiguous name
+  --> $DIR/wrong_self_convention.rs:152:21
    |
 LL |         fn from_i32(self);
    |                     ^^^^
 
-error: aborting due to 22 previous errors
+error: aborting due to 24 previous errors