IDEA-166582 No completion inside lambda when instance of contains lambda

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/DataFlowRunner.java

@@ -75,8 +75,7 @@ public class DataFlowRunner {
   private Collection<DfaMemoryState> createInitialStates(@NotNull PsiElement psiBlock, @NotNull InstructionVisitor visitor) {
     PsiElement container = PsiTreeUtil.getParentOfType(psiBlock, PsiClass.class, PsiLambdaExpression.class);
     if (container != null && (!(container instanceof PsiClass) || PsiUtil.isLocalOrAnonymousClass((PsiClass)container))) {
-      final PsiElement parent = container.getParent();
-      final PsiCodeBlock block = DfaPsiUtil.getTopmostBlockInSameClass(parent);
+      PsiElement block = DfaPsiUtil.getTopmostBlockInSameClass(container.getParent());
       if (block != null) {
         final RunnerResult result = analyzeMethod(block, visitor);
         if (result == RunnerResult.OK) {

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/DfaPsiUtil.java

@@ -336,29 +336,21 @@ public class DfaPsiUtil {
   }
 
   @Nullable
-  public static PsiCodeBlock getTopmostBlockInSameClass(@NotNull PsiElement position) {
-    PsiCodeBlock block = PsiTreeUtil.getParentOfType(position, PsiCodeBlock.class, false, PsiMember.class, PsiFile.class, PsiLambdaExpression.class);
-    if (block == null) {
-      return null;
-    }
-
-    PsiCodeBlock lastBlock = block;
-    while (true) {
-      block = PsiTreeUtil.getParentOfType(block, PsiCodeBlock.class, true, PsiMember.class, PsiFile.class, PsiLambdaExpression.class);
-      if (block == null) {
-        return lastBlock;
-      }
-      lastBlock = block;
-    }
+  public static PsiElement getTopmostBlockInSameClass(@NotNull PsiElement position) {
+    return JBIterable.
+      generate(position, PsiElement::getParent).
+      takeWhile(e -> !(e instanceof PsiMember || e instanceof PsiFile || e instanceof PsiLambdaExpression)).
+      filter(e -> e instanceof PsiCodeBlock || e instanceof PsiExpression && e.getParent() instanceof PsiLambdaExpression).
+      last();
   }
 
   @NotNull
   public static Collection<PsiExpression> getVariableAssignmentsInFile(@NotNull PsiVariable psiVariable,
                                                                        final boolean literalsOnly,
                                                                        final PsiElement place) {
-    final Ref<Boolean> modificationRef = Ref.create(Boolean.FALSE);
-    final PsiCodeBlock codeBlock = place == null? null : getTopmostBlockInSameClass(place);
-    final int placeOffset = codeBlock != null? place.getTextRange().getStartOffset() : 0;
+    Ref<Boolean> modificationRef = Ref.create(Boolean.FALSE);
+    PsiElement codeBlock = place == null? null : getTopmostBlockInSameClass(place);
+    int placeOffset = codeBlock != null? place.getTextRange().getStartOffset() : 0;
     PsiFile containingFile = psiVariable.getContainingFile();
     LocalSearchScope scope = new LocalSearchScope(new PsiElement[]{containingFile}, null, true);
     Collection<PsiReference> references = ReferencesSearch.search(psiVariable, scope).findAll();

java/java-tests/testData/codeInsight/completion/normal/CastInstanceofedQualifierInExpressionLambda.java

@@ -0,0 +1,8 @@
+public class Test {
+  public void f(Object o ) {
+    if (o instanceof String) {
+      Runnable r = () -> o.leng<caret>;
+    }
+  }
+
+}

java/java-tests/testData/codeInsight/completion/normal/CastInstanceofedQualifierInExpressionLambda_after.java

@@ -0,0 +1,8 @@
+public class Test {
+  public void f(Object o ) {
+    if (o instanceof String) {
+      Runnable r = () -> ((String) o).length()<caret>;
+    }
+  }
+
+}

java/java-tests/testSrc/com/intellij/codeInsight/completion/NormalCompletionDfaTest.groovy

@@ -72,4 +72,6 @@ public class FooImpl extends Foo {
 
   void testCastInstanceofedQualifierInLambda2() { doTest() }
 
+  void testCastInstanceofedQualifierInExpressionLambda() { doTest() }
+
 }