Corrected explicit_counter_loop missing lints if variable used after loop

Author: JoshMcguigan

clippy_lints/src/loops.rs

@@ -1996,6 +1996,9 @@ impl<'a, 'tcx> Visitor<'tcx> for InitializeVisitor<'a, 'tcx> {
         if self.state == VarState::DontWarn {
             return;
         }
+        if self.past_loop {
+            return;
+        }
         if SpanlessEq::new(self.cx).eq_expr(&expr, self.end_expr) {
             self.past_loop = true;
             return;
@@ -2024,12 +2027,7 @@ impl<'a, 'tcx> Visitor<'tcx> for InitializeVisitor<'a, 'tcx> {
                     _ => (),
                 }
             }
-
-            if self.past_loop {
-                self.state = VarState::DontWarn;
-                return;
-            }
-        } else if !self.past_loop && is_loop(expr) {
+        } else if is_loop(expr) {
             self.state = VarState::DontWarn;
             return;
         } else if is_conditional(expr) {

tests/ui/for_loop.rs

@@ -573,16 +573,45 @@ mod issue_2496 {
 }
 
 mod issue_1219 {
-    // potential false positive for explicit_counter_loop
+    #[warn(clippy::explicit_counter_loop)]
     pub fn test() {
-        let thing = 5;
+        // should not trigger the lint, because of the continue statement
         let text = "banana";
         let mut count = 0;
         for ch in text.chars() {
             if ch == 'a' {
                 continue;
             }
-            count += 1
+            count += 1;
+        }
+        println!("{}", count);
+
+        // should trigger the lint
+        let text = "banana";
+        let mut count = 0;
+        for ch in text.chars() {
+            if ch == 'a' {
+                println!("abc")
+            }
+            count += 1;
+        }
+        println!("{}", count);
+
+        // should not trigger the lint
+        let text = "banana";
+        let mut count = 0;
+        for ch in text.chars() {
+            if ch == 'a' {
+                count += 1;
+            }
+        }
+        println!("{}", count);
+
+        // should trigger the lint
+        let text = "banana";
+        let mut count = 0;
+        for _ch in text.chars() {
+            count += 1;
         }
         println!("{}", count);
     }