prefer `if let` to match with `None => {}` arm in some places

This is a spiritual succesor to #34268/8531d581, in which we replaced a
number of matches of None to the unit value with `if let` conditionals
where it was judged that this made for clearer/simpler code (as would be
recommended by Manishearth/rust-clippy's `single_match` lint). The same
rationale applies to matches of None to the empty block.

1 files changed, 3 insertions, 6 deletions

diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs
index 88be3ade839..c90c93e75ac 100644
--- a/src/libtest/lib.rs
+++ b/src/libtest/lib.rs
@@ -747,12 +747,9 @@ pub fn run_tests_console(opts: &TestOpts, tests: Vec<TestDescAndFn>) -> io::Resu
             PadOnRight => t.desc.name.as_slice().len(),
         }
     }
-    match tests.iter().max_by_key(|t| len_if_padded(*t)) {
-        Some(t) => {
-            let n = t.desc.name.as_slice();
-            st.max_name_len = n.len();
-        }
-        None => {}
+    if let Some(t) = tests.iter().max_by_key(|t| len_if_padded(*t)) {
+        let n = t.desc.name.as_slice();
+        st.max_name_len = n.len();
     }
     run_tests(opts, tests, |x| callback(&x, &mut st))?;
     return st.write_run_finish();