unreachable code: qualified fields and array access in assignments (IDEA-144428)

java/java-analysis-impl/src/com/intellij/codeInsight/daemon/impl/analysis/HighlightControlFlowUtil.java

@@ -95,7 +95,8 @@ public class HighlightControlFlowUtil {
     // do not compute constant expressions for if() statement condition
     // see JLS 14.20 Unreachable Statements
     try {
-      final ControlFlow controlFlow = getControlFlowNoConstantEvaluate(codeBlock);
+      AllVariablesControlFlowPolicy policy = AllVariablesControlFlowPolicy.getInstance();
+      final ControlFlow controlFlow = ControlFlowFactory.getInstance(codeBlock.getProject()).getControlFlow(codeBlock, policy, false, false);
       final PsiElement unreachableStatement = ControlFlowUtil.getUnreachableStatement(controlFlow);
       if (unreachableStatement != null) {
         String description = JavaErrorMessages.message("unreachable.statement");

java/java-psi-impl/src/com/intellij/psi/controlFlow/ControlFlowAnalyzer.java

@@ -1301,29 +1301,39 @@ class ControlFlowAnalyzer extends JavaElementVisitor {
       if (rExpr != null) {
         rExpr.accept(this);
       }
-      final PsiReferenceExpression referenceExpression = (PsiReferenceExpression)lExpr;
-      PsiExpression qualifierExpression = referenceExpression.getQualifierExpression();
-      PsiVariable variable = getUsedVariable(referenceExpression);
-      if (qualifierExpression == null ||
-          qualifierExpression instanceof PsiThisExpression ||
-          variable instanceof PsiField && variable.hasModifierProperty(PsiModifier.STATIC)) {
-        if (variable != null) {
-          if (myAssignmentTargetsAreElements) {
-            startElement(lExpr);
-          }
-
-          if (expression.getOperationTokenType() != JavaTokenType.EQ) {
-            generateReadInstruction(variable);
-          }
-          generateWriteInstruction(variable);
-
-          if (myAssignmentTargetsAreElements) finishElement(lExpr);
+      PsiVariable variable = getUsedVariable((PsiReferenceExpression)lExpr);
+      if (variable != null) {
+        if (myAssignmentTargetsAreElements) {
+          startElement(lExpr);
         }
+
+        if (expression.getOperationTokenType() != JavaTokenType.EQ) {
+          generateReadInstruction(variable);
+        }
+        generateWriteInstruction(variable);
+
+        if (myAssignmentTargetsAreElements) finishElement(lExpr);
       }
       else {
         lExpr.accept(this); //?
       }
     }
+    else if (lExpr instanceof PsiArrayAccessExpression &&
+             ((PsiArrayAccessExpression)lExpr).getArrayExpression() instanceof PsiReferenceExpression){
+      PsiVariable variable = getUsedVariable((PsiReferenceExpression)((PsiArrayAccessExpression)lExpr).getArrayExpression());
+      if (variable != null) {
+        generateReadInstruction(variable);
+        final PsiExpression indexExpression = ((PsiArrayAccessExpression)lExpr).getIndexExpression();
+        if (indexExpression != null) {
+          indexExpression.accept(this);
+        }
+      } else {
+        lExpr.accept(this);
+      }
+      if (rExpr != null) {
+        rExpr.accept(this);
+      }
+    }
     else if (lExpr != null) {
       lExpr.accept(this);
       if (rExpr != null) {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlighting6/UnreachableAssignments.java

@@ -0,0 +1,31 @@
+class Test {
+  String[] days = {"",""};
+
+  public static void foo1() {
+    for (; ; ) {
+      break;
+      <error descr="Unreachable statement">new Test().days = null;</error>
+    }
+  }
+  
+  void bar1() {
+    for (; ; ) {
+      break;
+      <error descr="Unreachable statement">days = null;</error>
+    }
+  }
+
+  static void foo2() {
+    for (; ; ) {
+      break;
+      <error descr="Unreachable statement">new Test().days[0] = null;</error>
+    }
+  }
+
+  void bar2() {
+    for (;;) {
+      break;
+      <error descr="Unreachable statement">days[0] = null;</error>
+    }
+  }
+}

java/java-tests/testData/refactoring/inlineLocal/ArrayMethodCallInitialized.java

@@ -1,8 +1,8 @@
 public class A {
 
   public void testInlineRefactoring() {
-    int[] array = ar();
-    arr<caret>ay[1] = 22;
+    int[] ar<caret>ray = ar();
+    array[1] = 22;
   }
 
   private int[] ar() {

java/java-tests/testSrc/com/intellij/codeInsight/daemon/LightAdvHighlightingJdk6Test.java

@@ -58,4 +58,5 @@ public class LightAdvHighlightingJdk6Test extends LightDaemonAnalyzerTestCase {
   public void testGenericArrayCreationWithGenericTypeWithOneUnboundedWildcardOneNormalParams() { doTest(false, false); }
   public void testAgentPremain() { doTest(false, false); }
   public void testInitializedBeforeUsed() { doTest(false, false); }
+  public void testUnreachableAssignments() { doTest(false, false); }
 }