add testcase for suggest self

src/test/ui/resolve/issue-103474.rs

@@ -13,4 +13,16 @@ impl S {
     }
 }
 
+// https://github.com/rust-lang/rust/pull/103531#discussion_r1004728080
+struct Foo {
+    i: i32,
+}
+
+impl Foo {
+    fn needs_self() {
+        this.i
+        //~^ ERROR cannot find value `this` in this scope
+    }
+}
+
 fn main() {}

src/test/ui/resolve/issue-103474.stderr

@@ -1,3 +1,18 @@
+error[E0425]: cannot find value `this` in this scope
+  --> $DIR/issue-103474.rs:23:9
+   |
+LL |         this.i
+   |         ^^^^ not found in this scope
+   |
+help: you might have meant to use `self` here instead
+   |
+LL |         self.i
+   |         ~~~~
+help: if you meant to use `self`, you are also missing a `self` receiver argument
+   |
+LL |     fn needs_self(&self) {
+   |                   +++++
+
 error[E0425]: cannot find function `first` in this scope
   --> $DIR/issue-103474.rs:6:9
    |
@@ -15,6 +30,6 @@ error[E0425]: cannot find function `no_method_err` in this scope
 LL |         no_method_err()
    |         ^^^^^^^^^^^^^ not found in this scope
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0425`.