Added comment to
`tests/ui/mismatched_types/assignment-mismatch-various-types.rs`

merge `tests/ui/mismatched_types/main.rs`

tests/ui/mismatched_types/assignment-mismatch-various-types.rs

diff --git a/tests/ui/mismatched_types/assignment-mismatch-various-types.rs b/tests/ui/mismatched_types/assignment-mismatch-various-types.rs
index eb94294..903bfd9 100644
--- a/tests/ui/mismatched_types/assignment-mismatch-various-types.rs
+++ b/tests/ui/mismatched_types/assignment-mismatch-various-types.rs
@@ -1,6 +1,9 @@
+//! regression test for <https://github.com/rust-lang/rust/issues/3477>
+
 fn main() {
+    let x: u32 = ();
+    //~^ ERROR mismatched types
+
     let _p: char = 100;
     //~^ ERROR mismatched types
-    //~| NOTE expected `char`, found `u8`
-    //~| NOTE expected due to this
 }

tests/ui/mismatched_types/assignment-mismatch-various-types.stderr

diff --git a/tests/ui/mismatched_types/assignment-mismatch-various-types.stderr b/tests/ui/mismatched_types/assignment-mismatch-various-types.stderr
index 2a4d6d2..14356fe 100644
--- a/tests/ui/mismatched_types/assignment-mismatch-various-types.stderr
+++ b/tests/ui/mismatched_types/assignment-mismatch-various-types.stderr
@@ -1,11 +1,19 @@
 error[E0308]: mismatched types
-  --> $DIR/issue-3477.rs:2:20
+  --> $DIR/assignment-mismatch-various-types.rs:4:18
+   |
+LL |     let x: u32 = ();
+   |            ---   ^^ expected `u32`, found `()`
+   |            |
+   |            expected due to this
+
+error[E0308]: mismatched types
+  --> $DIR/assignment-mismatch-various-types.rs:7:20
    |
 LL |     let _p: char = 100;
    |             ----   ^^^ expected `char`, found `u8`
    |             |
    |             expected due to this
 
-error: aborting due to 1 previous error
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0308`.

tests/ui/mismatched_types/main.rs

diff --git a/tests/ui/mismatched_types/main.rs b/tests/ui/mismatched_types/main.rs
deleted file mode 100644
index e2d09dc..0000000
--- a/tests/ui/mismatched_types/main.rs
+++ /dev/null
@@ -1,4 +0,0 @@
-fn main() {
-    let x: u32 = ( //~ ERROR mismatched types
-    );
-}

tests/ui/mismatched_types/main.stderr

diff --git a/tests/ui/mismatched_types/main.stderr b/tests/ui/mismatched_types/main.stderr
deleted file mode 100644
index 38146ce..0000000
--- a/tests/ui/mismatched_types/main.stderr
+++ /dev/null
@@ -1,13 +0,0 @@
-error[E0308]: mismatched types
-  --> $DIR/main.rs:2:18
-   |
-LL |       let x: u32 = (
-   |  ____________---___^
-   | |            |
-   | |            expected due to this
-LL | |     );
-   | |_____^ expected `u32`, found `()`
-
-error: aborting due to 1 previous error
-
-For more information about this error, try `rustc --explain E0308`.