[java-inspections] Detect new object from variable inside the loop

GitOrigin-RevId: b9f8537d8cea84fee3a008ec678d09e089205d52

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/bugs/NewObjectEqualityInspection.java

@@ -9,7 +9,6 @@ import com.intellij.psi.*;
 import com.intellij.psi.controlFlow.*;
 import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.PsiUtil;
-import com.intellij.util.containers.ContainerUtil;
 import com.siyeh.InspectionGadgetsBundle;
 import com.siyeh.ig.BaseInspection;
 import com.siyeh.ig.BaseInspectionVisitor;
@@ -21,8 +20,8 @@ import com.siyeh.ig.psiutils.VariableAccessUtils;
 import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.Collections;
 import java.util.List;
+import java.util.Set;
 
 import static com.intellij.util.ObjectUtils.tryCast;
 
@@ -99,8 +98,9 @@ public class NewObjectEqualityInspection extends BaseInspection {
       catch (AnalysisCanceledException e) {
         return expression;
       }
-      int start = flow.getEndOffset(initializer) + 1;
-      if (ControlFlowUtils.isVariableReferencedBeforeStatementEntry(flow, start, expression, variable, Collections.emptySet())) {
+      int initializerEnd = flow.getEndOffset(initializer);
+      int start = initializerEnd + 1;
+      if (ControlFlowUtils.isVariableReferencedBeforeStatementEntry(flow, start, expression, variable, Set.of(initializerEnd))) {
         return expression;
       }
       return initializer;

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/psiutils/ControlFlowUtils.java

@@ -880,7 +880,7 @@ public final class ControlFlowUtils {
           if (to == statementStart && (from < statementStart || from >= statementEnd)) {
             return true;
           }
-          if (!referenced.get(to)) {
+          if (!referenced.get(to) && !excluded.contains(to)) {
             referenced.set(to);
             changed = true;
           }

plugins/InspectionGadgets/test/com/siyeh/igtest/bugs/new_object_equality/ControlFlow.java

@@ -4,6 +4,17 @@ import java.util.*;
 
 public class ControlFlow
 {
+  void nonLeak(Object obj) {
+    while (true) {
+      Object obj2 = new Object();
+      if (obj == <warning descr="New object is compared using '=='">obj2</warning>) {
+        System.out.println("equal");
+      } else {
+        if (Math.random() > 0.5) return;
+      }
+    }
+  }
+
   void test() {
     while (true) {
       Object obj = new Object();