Do not lint when range is completely included into another one

Author: ThibsG

clippy_lints/src/matches.rs

@@ -1544,7 +1544,17 @@ where
                 }
             },
             (&Kind::End(a, _), &Kind::Start(b, _)) if a != Bound::Included(b) => (),
-            _ => return Some((a.range(), b.range())),
+            _ => {
+                // skip if the range `a` is completely included into the range `b`
+                if let Ordering::Equal | Ordering::Less = a.cmp(&b) {
+                    let kind_a = Kind::End(a.range().node.1, a.range());
+                    let kind_b = Kind::End(b.range().node.1, b.range());
+                    if let Ordering::Equal | Ordering::Greater = kind_a.cmp(&kind_b) {
+                        return None;
+                    }
+                }
+                return Some((a.range(), b.range()));
+            },
         }
     }
 

tests/ui/match_overlapping_arm.rs

@@ -57,6 +57,18 @@ fn overlapping() {
         _ => (),
     }
 
+    match 42 {
+        5..7 => println!("5 .. 7"),
+        0..10 => println!("0 .. 10"),
+        _ => (),
+    }
+
+    match 42 {
+        5..10 => println!("5 .. 10"),
+        0..=10 => println!("0 ... 10"),
+        _ => (),
+    }
+
     /*
     // FIXME(JohnTitor): uncomment this once rustfmt knows half-open patterns
     match 42 {

tests/ui/match_overlapping_arm.stderr

@@ -23,30 +23,6 @@ note: overlaps with this
 LL |         FOO..=11 => println!("0 ... 11"),
    |         ^^^^^^^^
 
-error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:26:9
-   |
-LL |         0..=5 => println!("0 ... 5"),
-   |         ^^^^^
-   |
-note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:25:9
-   |
-LL |         2 => println!("2"),
-   |         ^
-
-error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:32:9
-   |
-LL |         0..=2 => println!("0 ... 2"),
-   |         ^^^^^
-   |
-note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:31:9
-   |
-LL |         2 => println!("2"),
-   |         ^
-
 error: some ranges overlap
   --> $DIR/match_overlapping_arm.rs:55:9
    |
@@ -59,5 +35,5 @@ note: overlaps with this
 LL |         0..=11 => println!("0 ... 11"),
    |         ^^^^^^
 
-error: aborting due to 5 previous errors
+error: aborting due to 3 previous errors