Auto merge of rust-lang#13311 - alex-semenyuk:fix_manual_range_patter…

…ns, r=Manishearth

Fix manual_range_patterns case with one element at OR

Close rust-lang#11825
As mentioned rust-lang#11825 `OR` can be used for stylistic purposes with one element, we can filter this case from triggering lint

changelog: [`manual_range_patterns`]: not trigger when `OR` has only one element

clippy_lints/src/manual_range_patterns.rs

@@ -77,9 +77,10 @@ impl Num {
 impl LateLintPass<'_> for ManualRangePatterns {
     fn check_pat(&mut self, cx: &LateContext<'_>, pat: &'_ rustc_hir::Pat<'_>) {
         // a pattern like 1 | 2 seems fine, lint if there are at least 3 alternatives
-        // or at least one range
+        // or more then one range (exclude triggering on stylistic using OR with one element
+        // like described https://github.com/rust-lang/rust-clippy/issues/11825)
         if let PatKind::Or(pats) = pat.kind
-            && (pats.len() >= 3 || pats.iter().any(|p| matches!(p.kind, PatKind::Range(..))))
+            && (pats.len() >= 3 || (pats.len() > 1 && pats.iter().any(|p| matches!(p.kind, PatKind::Range(..)))))
             && !in_external_macro(cx.sess(), pat.span)
         {
             let mut min = Num::dummy(i128::MAX);

tests/ui/manual_range_patterns.fixed

@@ -45,4 +45,12 @@ fn main() {
         };
     }
     mac!(f);
+
+    #[rustfmt::skip]
+    let _ = match f {
+        | 2..=15 => 4,
+        | 241..=254 => 5,
+        | 255 => 6,
+        | _ => 7,
+    };
 }

tests/ui/manual_range_patterns.rs

@@ -45,4 +45,12 @@ fn main() {
         };
     }
     mac!(f);
+
+    #[rustfmt::skip]
+    let _ = match f {
+        | 2..=15 => 4,
+        | 241..=254 => 5,
+        | 255 => 6,
+        | _ => 7,
+    };
 }