add note about update-all-refs script, revert redundant pat to master

clippy_lints/src/if_let_mutex.rs

@@ -64,14 +64,10 @@ impl LateLintPass<'_, '_> for IfLetMutex {
 }
 
 fn matching_arm(arm: &Arm<'_>, op: &Expr<'_>, ex: &Expr<'_>, cx: &LateContext<'_, '_>) -> bool {
-    if_chain! {
+    if let ExprKind::Block(ref block, _l) = arm.body.kind {
-        if let ExprKind::Block(ref block, _l) = arm.body.kind;
+        block.stmts.iter().any(|stmt| matching_stmt(stmt, op, ex, cx))
-        if block.stmts.iter().any(|stmt| matching_stmt(stmt, op, ex, cx));
+    } else {
-        then {
+        false
-            true
-        } else {
-            false
-        }
     }
 }
 

doc/adding_lints.md

@@ -101,7 +101,9 @@ Once we are satisfied with the output, we need to run
 Please note that, we should run `TESTNAME=foo_functions cargo uitest`
 every time before running `tests/ui/update-all-references.sh`.
 Running `TESTNAME=foo_functions cargo uitest` should pass then. When we commit
-our lint, we need to commit the generated `.stderr` files, too.
+our lint, we need to commit the generated `.stderr` files, too. In general you
+should only run `tests/ui/update-all-references.sh` for the specific lint you are
+creating/editing.
 
 ## Rustfix tests
 

tests/ui/redundant_pattern_matching.rs

@@ -85,7 +85,6 @@ fn main() {
 
     let _ = does_something();
     let _ = returns_unit();
-    let _ = issue_5271();
 
     let opt = Some(false);
     let x = if let Some(_) = opt { true } else { false };