captured wildcard in subtyping constraints: use upper bound only (IDEA-139046)

java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/graphInference/constraints/SubtypingConstraint.java

@@ -72,9 +72,9 @@ public class SubtypingConstraint implements ConstraintFormula {
       }
 
       if (tBound instanceof PsiCapturedWildcardType) {
-        tBound = ((PsiWildcardType)myT).isExtends() ? ((PsiCapturedWildcardType)tBound).getUpperBound() 
-                                                    : ((PsiCapturedWildcardType)tBound).getLowerBound();
+        tBound = ((PsiCapturedWildcardType)tBound).getUpperBound();
       }
+
       if (myS instanceof PsiCapturedWildcardType) {
         myS = ((PsiCapturedWildcardType)myS).getWildcard();
       }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/constraints/SubtypingConstraintWithSuperCapturedWildcard.java

@@ -0,0 +1,11 @@
+import java.util.Map;
+import java.util.stream.Stream;
+
+import static java.util.stream.Collectors.toMap;
+
+class Test {
+  Map<String, String> foo(Stream<? extends String> stream) {
+    return stream.collect(toMap(s -> s, s -> s));
+  }
+}
+

java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/ConstraintsInferenceMiscTest.java

@@ -20,9 +20,6 @@ import com.intellij.openapi.projectRoots.Sdk;
 import com.intellij.testFramework.IdeaTestUtil;
 import org.jetbrains.annotations.NonNls;
 
-/**
- * Created by anna on 1/31/14.
- */
 public class ConstraintsInferenceMiscTest extends LightDaemonAnalyzerTestCase {
   @NonNls static final String BASE_PATH = "/codeInsight/daemonCodeAnalyzer/lambda/constraints";
 
@@ -62,6 +59,10 @@ public class ConstraintsInferenceMiscTest extends LightDaemonAnalyzerTestCase {
     doTest(false);
   }
 
+  public void testSubtypingConstraintWithSuperCapturedWildcard() throws Exception {
+    doTest(false);
+  }
+
   private void doTest(final boolean checkWarnings) {
     doTest(BASE_PATH + "/" + getTestName(false) + ".java", checkWarnings, false);
   }