From 47816dcc2109e3368b5affec572be31e8f2a18d2 Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Sun, 28 Oct 2012 18:11:46 +0100
Subject: [PATCH] suppress constant condition reporting for any expression
 involving getters (IDEA-93244)

---
 .../dataFlow/DataFlowInspection.java          |  2 +-
 .../dataFlow/StandardInstructionVisitor.java  | 15 ++++++++----
 .../dataFlow/fixture/ThisFieldGetters.java    | 23 +++++++++++++++++++
 .../DataFlowInspectionFixtureTest.java        |  1 +
 4 files changed, 36 insertions(+), 5 deletions(-)
 create mode 100644 java/java-tests/testData/inspection/dataFlow/fixture/ThisFieldGetters.java

diff --git a/java/java-impl/src/com/intellij/codeInspection/dataFlow/DataFlowInspection.java b/java/java-impl/src/com/intellij/codeInspection/dataFlow/DataFlowInspection.java
index 4d91e400d137..48ad2cc6a58a 100644
--- a/java/java-impl/src/com/intellij/codeInspection/dataFlow/DataFlowInspection.java
+++ b/java/java-impl/src/com/intellij/codeInspection/dataFlow/DataFlowInspection.java
@@ -283,7 +283,7 @@ public class DataFlowInspection extends BaseLocalInspectionTool {
           createSimplifyToAssignmentFix()
         );
       }
-      else if (shouldReportConditionAlwaysTrueOrFalse(psiAnchor, evaluatesToTrue) && !visitor.silenceConstantCondition(instruction)) {
+      else if (shouldReportConditionAlwaysTrueOrFalse(psiAnchor, evaluatesToTrue) && !visitor.silenceConstantCondition(psiAnchor)) {
         final LocalQuickFix fix = createSimplifyBooleanExpressionFix(psiAnchor, evaluatesToTrue);
         String message = InspectionsBundle.message(underBinary ?
                                                    "dataflow.message.constant.condition.when.reached" :
diff --git a/java/java-impl/src/com/intellij/codeInspection/dataFlow/StandardInstructionVisitor.java b/java/java-impl/src/com/intellij/codeInspection/dataFlow/StandardInstructionVisitor.java
index f2ecef1f8f4d..6080e4ebf058 100644
--- a/java/java-impl/src/com/intellij/codeInspection/dataFlow/StandardInstructionVisitor.java
+++ b/java/java-impl/src/com/intellij/codeInspection/dataFlow/StandardInstructionVisitor.java
@@ -20,8 +20,10 @@ import com.intellij.codeInspection.dataFlow.instructions.*;
 import com.intellij.codeInspection.dataFlow.value.*;
 import com.intellij.psi.*;
 import com.intellij.psi.tree.IElementType;
+import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.TypeConversionUtil;
 import com.intellij.util.ArrayUtil;
+import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.containers.FactoryMap;
 import gnu.trove.THashSet;
 import org.jetbrains.annotations.NotNull;
@@ -36,7 +38,7 @@ import java.util.Set;
 public class StandardInstructionVisitor extends InstructionVisitor {
   private final Set<BinopInstruction> myReachable = new THashSet<BinopInstruction>();
   private final Set<BinopInstruction> myCanBeNullInInstanceof = new THashSet<BinopInstruction>();
-  private final Set<BinopInstruction> myNotToReportReachability = new THashSet<BinopInstruction>();
+  private final Set<PsiElement> myNotToReportReachability = new THashSet<PsiElement>();
   private final Set<InstanceofInstruction> myUsefulInstanceofs = new THashSet<InstanceofInstruction>();
   private final FactoryMap<MethodCallInstruction, boolean[]> myParametersNotNull = new FactoryMap<MethodCallInstruction, boolean[]>() {
     @Override
@@ -328,7 +330,7 @@ public class StandardInstructionVisitor extends InstructionVisitor {
     }
 
     if (isViaMethods(dfaLeft) || isViaMethods(dfaRight)) {
-      myNotToReportReachability.add(instruction);
+      ContainerUtil.addIfNotNull(myNotToReportReachability, instruction.getPsiAnchor());
     }
     myCanBeNullInInstanceof.add(instruction);
 
@@ -435,7 +437,12 @@ public class StandardInstructionVisitor extends InstructionVisitor {
     return myCanBeNullInInstanceof.contains(instruction);
   }
 
-  public boolean silenceConstantCondition(BranchingInstruction instruction) {
-    return instruction instanceof BinopInstruction && myNotToReportReachability.contains(instruction);
+  public boolean silenceConstantCondition(@Nullable PsiElement element) {
+    for (PsiElement skipped : myNotToReportReachability) {
+      if (PsiTreeUtil.isAncestor(element, skipped, false)) {
+        return true;
+      }
+    }
+    return false;
   }
 }
diff --git a/java/java-tests/testData/inspection/dataFlow/fixture/ThisFieldGetters.java b/java/java-tests/testData/inspection/dataFlow/fixture/ThisFieldGetters.java
new file mode 100644
index 000000000000..c732b18f823b
--- /dev/null
+++ b/java/java-tests/testData/inspection/dataFlow/fixture/ThisFieldGetters.java
@@ -0,0 +1,23 @@
+class Test {
+
+  private int count1;
+  private int count2;
+
+  public void test() {
+    int oldCount1 = getCount1();
+    int oldCount2 = getCount2();
+    count1++;
+    if (oldCount1 != getCount1() || oldCount2 != getCount2()) {
+      System.out.println("changed");
+    }
+  }
+
+  private int getCount1() {
+    return count1;
+  }
+
+  private int getCount2() {
+    return count2;
+  }
+
+}
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/codeInspection/DataFlowInspectionFixtureTest.java b/java/java-tests/testSrc/com/intellij/codeInspection/DataFlowInspectionFixtureTest.java
index e32605c17a37..e4f0751aac17 100644
--- a/java/java-tests/testSrc/com/intellij/codeInspection/DataFlowInspectionFixtureTest.java
+++ b/java/java-tests/testSrc/com/intellij/codeInspection/DataFlowInspectionFixtureTest.java
@@ -81,6 +81,7 @@ public class DataFlowInspectionFixtureTest extends JavaCodeInsightFixtureTestCas
 
   public void testChainedFinalFieldsDfa() throws Throwable { doTest(); }
   public void testFinalFieldsDifferentInstances() throws Throwable { doTest(); }
+  public void testThisFieldGetters() throws Throwable { doTest(); }
   public void testChainedFinalFieldAccessorsDfa() throws Throwable { doTest(); }
 
   public void testAssigningUnknownToNullable() throws Throwable { doTest(); }