[unnecessary_literal_unwrap]: also handle unwrap_err_unchecked

Author: y21

clippy_lints/src/methods/mod.rs

@@ -3973,6 +3973,9 @@ impl Methods {
                     unnecessary_literal_unwrap::check(cx, expr, recv, name, args);
                     unwrap_used::check(cx, expr, recv, true, self.allow_unwrap_in_tests);
                 },
+                ("unwrap_err_unchecked", []) => {
+                    unnecessary_literal_unwrap::check(cx, expr, recv, name, args);
+                }
                 ("unwrap_or", [u_arg]) => {
                     match method_call(recv) {
                         Some((arith @ ("checked_add" | "checked_sub" | "checked_mul"), lhs, [rhs], _, _)) => {

clippy_lints/src/methods/unnecessary_literal_unwrap.rs

@@ -62,7 +62,7 @@ pub(super) fn check(
                 (expr.span.with_hi(args[0].span.lo()), "panic!(".to_string()),
                 (expr.span.with_lo(args[0].span.hi()), ")".to_string()),
             ]),
-            ("Some" | "Ok", "unwrap_unchecked", _) => {
+            ("Some" | "Ok", "unwrap_unchecked", _) | ("Err", "unwrap_err_unchecked", _) => {
                 let mut suggs = vec![
                     (recv.span.with_hi(call_args[0].span.lo()), String::new()),
                     (expr.span.with_lo(call_args[0].span.hi()), String::new()),

tests/ui/unnecessary_literal_unwrap.fixed

@@ -75,6 +75,7 @@ fn unwrap_unchecked() {
     let _ = 1;
     let _ = unsafe { 1 + *(&1 as *const i32) };
     let _ = 1 + 1;
+    let _ = 123;
 }
 
 fn main() {

tests/ui/unnecessary_literal_unwrap.rs

@@ -75,6 +75,7 @@ fn unwrap_unchecked() {
     let _ = unsafe { Ok::<_, ()>(1).unwrap_unchecked() };
     let _ = unsafe { Ok::<_, ()>(1).unwrap_unchecked() + *(&1 as *const i32) };
     let _ = unsafe { Ok::<_, ()>(1).unwrap_unchecked() } + 1;
+    let _ = unsafe { Err::<(), i32>(123).unwrap_err_unchecked() };
 }
 
 fn main() {

tests/ui/unnecessary_literal_unwrap.stderr

@@ -481,5 +481,17 @@ LL -     let _ = unsafe { Ok::<_, ()>(1).unwrap_unchecked() } + 1;
 LL +     let _ = 1 + 1;
    |
 
-error: aborting due to 42 previous errors
+error: used `unwrap_err_unchecked()` on `Err` value
+  --> $DIR/unnecessary_literal_unwrap.rs:78:22
+   |
+LL |     let _ = unsafe { Err::<(), i32>(123).unwrap_err_unchecked() };
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: remove the `Err` and `unwrap_err_unchecked()`
+   |
+LL -     let _ = unsafe { Err::<(), i32>(123).unwrap_err_unchecked() };
+LL +     let _ = 123;
+   |
+
+error: aborting due to 43 previous errors