Java: report more "variable might have been assigned to" problems

GitOrigin-RevId: 030936b065bb00b504a69bc08ad39ae8a28cad6f

java/java-psi-impl/src/com/intellij/psi/controlFlow/ControlFlowUtil.java

@@ -2624,16 +2624,14 @@ public final class ControlFlowUtil {
   }
 
   public static @NotNull Collection<VariableInfo> getInitializedTwice(@NotNull ControlFlow flow, int startOffset, int endOffset) {
+    Collection<VariableInfo> result = new HashSet<>();
     while (startOffset < endOffset) {
       InitializedTwiceClientVisitor visitor = new InitializedTwiceClientVisitor(flow, startOffset);
       depthFirstSearch(flow, visitor, startOffset, endOffset);
-      Collection<VariableInfo> result = visitor.getResult();
-      if (!result.isEmpty()) {
-        return result;
-      }
+      result.addAll(visitor.getResult());
       startOffset = findUnprocessed(startOffset, endOffset, visitor);
     }
-    return Collections.emptyList();
+    return result;
   }
 
   private static class InitializedTwiceClientVisitor extends InstructionClientVisitor<Collection<VariableInfo>> {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlighting/AssignToFinal.java

@@ -160,6 +160,15 @@ class ForLoop {
       break;
     }
   }
+  
+  void x() {
+    final int a, b;
+    <error descr="Variable 'a' might already have been assigned to">a</error> = a = 0;
+    for (;; b = 0) {
+      <error descr="Variable 'b' might already have been assigned to">b</error> = 1;
+      break;
+    }
+  }
 }
 // IDEA-186305
 class Asserts {