support captured types in incomplete overloaded lambda completion (IDEA-155188)

java/java-impl/src/com/intellij/codeInsight/completion/JavaCompletionUtil.java

@@ -270,16 +270,9 @@ public class JavaCompletionUtil {
               final int parameterIndex = lambdaExpression.getParameterList().getParameterIndex((PsiParameter)resolve);
               final Set<LookupElement> set = new LinkedHashSet<LookupElement>();
               final boolean overloadsFound = LambdaUtil.processParentOverloads(lambdaExpression, functionalInterfaceType -> {
-                PsiType qualifierType = LambdaUtil.getLambdaParameterFromType(functionalInterfaceType, parameterIndex);
+                PsiType qualifierType = removeTopLevelWildcards(LambdaUtil.getLambdaParameterFromType(functionalInterfaceType, parameterIndex));
                 if (qualifierType == null) return;
 
-                if (qualifierType instanceof PsiWildcardType) {
-                  PsiType bound = ((PsiWildcardType)qualifierType).getBound();
-                  if (bound != null) {
-                    qualifierType = bound;
-                  }
-                }
-
                 PsiReferenceExpression fakeRef = createReference("xxx.xxx", createContextWithXxxVariable(element, qualifierType));
                 set.addAll(processJavaQualifiedReference(fakeRef.getReferenceNameElement(), fakeRef, elementFilter, options, matcher, parameters));
               });
@@ -288,10 +281,21 @@ public class JavaCompletionUtil {
           }
         }
       }
-    } 
+    }
     return processJavaQualifiedReference(element, javaReference, elementFilter, options, matcher, parameters);
   }
-  
+
+  @Nullable
+  private static PsiType removeTopLevelWildcards(@Nullable PsiType qualifierType) {
+    if (qualifierType instanceof PsiCapturedWildcardType) {
+      return removeTopLevelWildcards(((PsiCapturedWildcardType)qualifierType).getWildcard());
+    }
+    if (qualifierType instanceof PsiWildcardType) {
+      return removeTopLevelWildcards(((PsiWildcardType)qualifierType).getBound());
+    }
+    return qualifierType;
+  }
+
   private static Set<LookupElement> processJavaQualifiedReference(PsiElement element, PsiJavaReference javaReference, ElementFilter elementFilter,
                                                         JavaCompletionProcessor.Options options,
                                                         final PrefixMatcher matcher, CompletionParameters parameters) {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/completion/normal/LambdaWithCapturedSuperWildcardInAmbiguousCall.java

@@ -0,0 +1,8 @@
+import java.util.stream.*;
+import java.util.*;
+
+class Foo {
+  void main(Stream<? super String> stream) {
+    stream.collect(Collectors.toMap(o -> o.sub<caret>))
+  }
+}

java/java-tests/testSrc/com/intellij/codeInsight/completion/Normal8CompletionTest.groovy

@@ -244,6 +244,10 @@ class Test88 {
     configureByTestName()
     myFixture.assertPreferredCompletionItems(0, 'substring', 'substring', 'subSequence')
   }
+  public void testLambdaWithCapturedSuperWildcardInAmbiguousCall() {
+    configureByTestName()
+    myFixture.assertPreferredCompletionItems(0, 'substring', 'substring', 'subSequence')
+  }
   public void testUnexpectedLambdaInAmbiguousCall() { doAntiTest() }
 
   public void testNoCollectorsInComment() { doAntiTest() }