Java: Detect trivial duplicates containing 'break' and 'continue' (IDEA-182195)

java/java-analysis-impl/src/com/intellij/refactoring/util/duplicates/DuplicatesFinder.java

@@ -267,6 +267,9 @@ public class DuplicatesFinder {
           if (returnValue == null) {
             returnValue = myReturnValue;
           }
+          if (returnValue instanceof GotoReturnValue) {
+            return false;
+          }
           if (returnValue instanceof VariableReturnValue) {
             final ReturnValue value = match.getOutputVariableValue(((VariableReturnValue)returnValue).getVariable());
             if (value != null) {
@@ -284,7 +287,7 @@ public class DuplicatesFinder {
         return true;
       }
     }
-    catch (AnalysisCanceledException e) {
+    catch (AnalysisCanceledException ignored) {
     }
     return false;
   }

java/java-tests/testData/refactoring/extractMethod/InferredNotNullInReturnStatementDuplicate.java

@@ -0,0 +1,20 @@
+public class InferredNotNullInReturnStatementDuplicate {
+    void foo(java.util.List l) {
+        for (Object o : l) {
+            <selection>
+            if (o == null) continue;
+            Object x = bar(o);</selection>
+            System.out.println(x);
+        }
+    }
+
+    void bar(java.util.List l) {
+        for (Object o : l) {
+            if (o == null) continue;
+            Object x = bar(o);
+            System.out.println(x);
+        }
+    }
+
+    private String bar(Object o) {return "";}
+}

java/java-tests/testData/refactoring/extractMethod/InferredNotNullInReturnStatementDuplicate_after.java

@@ -0,0 +1,29 @@
+import org.jetbrains.annotations.Nullable;
+
+public class InferredNotNullInReturnStatementDuplicate {
+    void foo(java.util.List l) {
+        for (Object o : l) {
+
+            Object x = newMethod(o);
+            if (x == null) continue;
+            System.out.println(x);
+        }
+    }
+
+    @Nullable
+    private Object newMethod(Object o) {
+        if (o == null) return null;
+        Object x = bar(o);
+        return x;
+    }
+
+    void bar(java.util.List l) {
+        for (Object o : l) {
+            Object x = newMethod(o);
+            if (x == null) continue;
+            System.out.println(x);
+        }
+    }
+
+    private String bar(Object o) {return "";}
+}

java/java-tests/testData/refactoring/extractMethod/NullableCheckBreakDuplicate.java

@@ -0,0 +1,31 @@
+import java.util.List;
+
+public class NullableCheckBreakDuplicate {
+    List<Pojo> things;
+
+    void foo() {
+        while (true) {
+            <selection>
+            Pojo x = things.get(0);
+
+            if (x.it > 0) break;
+            things.remove(x);</selection>
+            System.out.println(x.it);
+        }
+    }
+
+    void baz() {
+        while (true) {
+            Pojo x = things.get(0);
+
+            if (x.it > 0) break;
+            things.remove(x);
+            System.out.println(x.it);
+        }
+    }
+
+    static class Pojo {
+        double it;
+        Pojo(double w) { it = w; }
+    }
+}

java/java-tests/testData/refactoring/extractMethod/NullableCheckBreakDuplicate_after.java

@@ -0,0 +1,38 @@
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+
+public class NullableCheckBreakDuplicate {
+    List<Pojo> things;
+
+    void foo() {
+        while (true) {
+
+            Pojo x = newMethod();
+            if (x == null) break;
+            System.out.println(x.it);
+        }
+    }
+
+    @Nullable
+    private Pojo newMethod() {
+        Pojo x = things.get(0);
+
+        if (x.it > 0) return null;
+        things.remove(x);
+        return x;
+    }
+
+    void baz() {
+        while (true) {
+            Pojo x = newMethod();
+            if (x == null) break;
+            System.out.println(x.it);
+        }
+    }
+
+    static class Pojo {
+        double it;
+        Pojo(double w) { it = w; }
+    }
+}

java/java-tests/testSrc/com/intellij/java/refactoring/ExtractMethodTest.java

@@ -1161,6 +1161,15 @@ public class ExtractMethodTest extends LightCodeInsightTestCase {
     doTest();
   }
 
+  public void testInferredNotNullInReturnStatementDuplicate() throws Exception {
+    doDuplicatesTest();
+  }
+
+  public void testNullableCheckBreakDuplicate() throws Exception {
+    doDuplicatesTest();
+  }
+
+
   private void doTestDisabledParam() throws PrepareFailedException {
     final CodeStyleSettings settings = CodeStyleSettingsManager.getSettings(getProject());
     settings.ELSE_ON_NEW_LINE = true;