From b01db09ad70298d424f9d21ada11b995cd23ebe5 Mon Sep 17 00:00:00 2001
From: Tagir Valeev <Tagir.Valeev@jetbrains.com>
Date: Thu, 19 Sep 2019 11:41:14 +0700
Subject: [PATCH] DFA: provide range info for variable even when qualifier is
 unknown

GitOrigin-RevId: 9cb8bce64df614e5c88572e739ee1ed49a92fd81
---
 .../codeInspection/dataFlow/value/DfaFactMapValue.java |  3 ++-
 .../dataFlow/value/VariableDescriptor.java             |  6 +++++-
 .../dataFlow/fixture/LongRangeKnownMethods.java        | 10 +++++++++-
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/DfaFactMapValue.java b/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/DfaFactMapValue.java
index c56e5bc076cc..6eb02e91c5c4 100644
--- a/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/DfaFactMapValue.java
+++ b/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/DfaFactMapValue.java
@@ -21,7 +21,8 @@ public class DfaFactMapValue extends DfaValue {
   }
 
   public <T> DfaValue withFact(@NotNull DfaFactType<T> factType, @Nullable T value) {
-    return getFactory().getFactFactory().createValue(myFacts.with(factType, value));
+    DfaFactMap newFacts = myFacts.with(factType, value);
+    return newFacts == myFacts ? this : getFactory().getFactFactory().createValue(newFacts);
   }
 
   public DfaFactMap getFacts() {
diff --git a/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/VariableDescriptor.java b/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/VariableDescriptor.java
index 326112220ee4..ddbfa442c50e 100644
--- a/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/VariableDescriptor.java
+++ b/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/VariableDescriptor.java
@@ -1,7 +1,9 @@
 // Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.codeInspection.dataFlow.value;
 
+import com.intellij.codeInspection.dataFlow.DfaFactType;
 import com.intellij.codeInspection.dataFlow.DfaPsiUtil;
+import com.intellij.codeInspection.dataFlow.rangeSet.LongRangeSet;
 import com.intellij.psi.PsiModifierListOwner;
 import com.intellij.psi.PsiType;
 import org.jetbrains.annotations.NotNull;
@@ -59,7 +61,9 @@ public interface VariableDescriptor {
       return factory.getVarFactory().createVariableValue(this, (DfaVariableValue)qualifier);
     }
     PsiType type = getType(null);
-    return factory.createTypeValue(type, DfaPsiUtil.getElementNullability(type, getPsiElement()));
+    LongRangeSet range = LongRangeSet.fromPsiElement(getPsiElement());
+    return factory.withFact(factory.createTypeValue(type, DfaPsiUtil.getElementNullability(type, getPsiElement())),
+                            DfaFactType.RANGE, range);
   }
 
   /**
diff --git a/java/java-tests/testData/inspection/dataFlow/fixture/LongRangeKnownMethods.java b/java/java-tests/testData/inspection/dataFlow/fixture/LongRangeKnownMethods.java
index 13dfcb6627ed..1a17771bdd74 100644
--- a/java/java-tests/testData/inspection/dataFlow/fixture/LongRangeKnownMethods.java
+++ b/java/java-tests/testData/inspection/dataFlow/fixture/LongRangeKnownMethods.java
@@ -352,7 +352,15 @@ public class LongRangeKnownMethods {
       if (<warning descr="Condition 's.length() > 7' is always 'false'">s.length() > 7</warning>) {}
     }
   }
-  
+
+  void testChainCall() {
+    if (<warning descr="Condition 'getByte(0).intValue() == 256' is always 'false'">getByte(0).intValue() == 256</warning>) {
+
+    }
+  }
+
+  native Byte getByte(int x);
+
   void testNumberToStringExact(boolean b) {
     int i = b ? 123 : 456;
     String s = Integer.toString(i);