From 4ba13155147ac1e5bee2e203f99f7611dcf99533 Mon Sep 17 00:00:00 2001
From: Tagir Valeev <Tagir.Valeev@jetbrains.com>
Date: Tue, 2 Apr 2019 09:57:25 +0700
Subject: [PATCH] IDEA-210123 BoxedLong.equals(BoxedInteger) is incorrectly
 reported as 'always true' when their unboxed value is the same

---
 .../dataFlow/DfaMemoryStateImpl.java             | 16 ++++++++++++++++
 .../dataFlow/fixture/EqualityLongInteger.java    | 10 ++++++++++
 .../codeInspection/DataFlowInspectionTest.java   |  1 +
 3 files changed, 27 insertions(+)
 create mode 100644 java/java-tests/testData/inspection/dataFlow/fixture/EqualityLongInteger.java

diff --git a/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/DfaMemoryStateImpl.java b/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/DfaMemoryStateImpl.java
index 6a68e0cd91d8..a6d1df962168 100644
--- a/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/DfaMemoryStateImpl.java
+++ b/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/DfaMemoryStateImpl.java
@@ -1134,6 +1134,13 @@ public class DfaMemoryStateImpl implements DfaMemoryState {
         dfaRight instanceof DfaVariableValue && !TypeConversionUtil.isPrimitiveWrapper(dfaRight.getType())) {
       return true;
     }
+    PsiType leftType = getPsiType(dfaLeft);
+    PsiType rightType = getPsiType(dfaRight);
+    if (TypeConversionUtil.isPrimitiveWrapper(leftType) && 
+        TypeConversionUtil.isPrimitiveWrapper(rightType) && !leftType.equals(rightType)) {
+      // Boxes of different type (e.g. Long and Integer), cannot be equal even if unboxed values are equal
+      return negated;
+    }
 
     DfaValue unboxedLeft = SpecialField.UNBOX.createValue(myFactory, dfaLeft);
     DfaValue unboxedRight = SpecialField.UNBOX.createValue(myFactory, dfaRight);
@@ -1149,6 +1156,15 @@ public class DfaMemoryStateImpl implements DfaMemoryState {
     return applyRelation(unboxedLeft, unboxedRight, negated);
   }
 
+  @Nullable
+  private static PsiType getPsiType(@NotNull DfaValue value) {
+    if (value instanceof DfaFactMapValue) {
+      TypeConstraint constraint = ((DfaFactMapValue)value).get(DfaFactType.TYPE_CONSTRAINT);
+      return constraint == null ? null : constraint.getPsiType();
+    }
+    return value.getType();
+  }
+
   private boolean checkCompareWithBooleanLiteral(DfaValue dfaLeft, DfaValue dfaRight, boolean negated) {
     if (dfaRight instanceof DfaConstValue) {
       Object constVal = ((DfaConstValue)dfaRight).getValue();
diff --git a/java/java-tests/testData/inspection/dataFlow/fixture/EqualityLongInteger.java b/java/java-tests/testData/inspection/dataFlow/fixture/EqualityLongInteger.java
new file mode 100644
index 000000000000..9155404b6b65
--- /dev/null
+++ b/java/java-tests/testData/inspection/dataFlow/fixture/EqualityLongInteger.java
@@ -0,0 +1,10 @@
+class Main {
+
+  public static void main(String[] args) {
+    Integer a = 1;
+    Integer b = 2;
+    Long c = 3L;
+    System.out.println(true);
+    System.out.println(<warning descr="Result of 'c.equals(a+b)' is always 'false'">c.equals(a+b)</warning>);
+  }
+}
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java b/java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java
index 95c1dd599a9a..5c6be33e5817 100644
--- a/java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java
+++ b/java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java
@@ -661,4 +661,5 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
   public void testInlineSimpleMethods() { doTest(); }
   public void testInferenceForNonStableParameters() { doTest(); }
   public void testNullableTernaryInConstructor() { doTest(); }
+  public void testEqualityLongInteger() { doTest(); }
 }