From 4290a37a08df4ce2e8a2320b183dd847e168a3cb Mon Sep 17 00:00:00 2001
From: "Anna.Kozlova" <anna.kozlova@jetbrains.com>
Date: Wed, 7 Dec 2016 12:21:37 +0100
Subject: [PATCH] new inference: check intersection type of upper bound to
 detect substitution (IDEA-165011)

---
 .../constraints/StrictSubtypingConstraint.java         | 10 ++++++++++
 .../graphInference/RecursiveTypeWithCapture.java       | 10 ++++++++++
 .../daemon/lambda/GraphInferenceHighlightingTest.java  |  4 ++++
 3 files changed, 24 insertions(+)
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/graphInference/RecursiveTypeWithCapture.java

diff --git a/java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/graphInference/constraints/StrictSubtypingConstraint.java b/java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/graphInference/constraints/StrictSubtypingConstraint.java
index 298228c3f408..bb0d2fe4179f 100644
--- a/java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/graphInference/constraints/StrictSubtypingConstraint.java
+++ b/java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/graphInference/constraints/StrictSubtypingConstraint.java
@@ -20,6 +20,7 @@ import com.intellij.psi.impl.source.resolve.graphInference.InferenceBound;
 import com.intellij.psi.impl.source.resolve.graphInference.InferenceSession;
 import com.intellij.psi.impl.source.resolve.graphInference.InferenceVariable;
 import com.intellij.psi.util.InheritanceUtil;
+import com.intellij.psi.util.PsiUtil;
 import com.intellij.psi.util.TypeConversionUtil;
 
 import java.util.HashSet;
@@ -135,6 +136,15 @@ public class StrictSubtypingConstraint implements ConstraintFormula {
           if (upperBound instanceof PsiClassType) {
             sType = (PsiClassType)upperBound;
           }
+          else if (upperBound instanceof PsiIntersectionType) {
+            for (PsiType type : ((PsiIntersectionType)upperBound).getConjuncts()) {
+              PsiClass sCandidate = PsiUtil.resolveClassInClassTypeOnly(type);
+              if (sCandidate != null && InheritanceUtil.isInheritorOrSelf(sCandidate, CClass, true)) {
+                sType = (PsiClassType)type;
+                break;
+              }
+            }
+          }
         }
 
         if (sType == null) return false;
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/graphInference/RecursiveTypeWithCapture.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/graphInference/RecursiveTypeWithCapture.java
new file mode 100644
index 000000000000..1fd1113ee321
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/graphInference/RecursiveTypeWithCapture.java
@@ -0,0 +1,10 @@
+
+import java.util.List;
+
+class Test {
+  <B> void foo(final Enum<? extends List<B>> f) {}
+
+  void bar(final Enum<? extends List<String>> e) {
+    foo(e);
+  }
+}
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/GraphInferenceHighlightingTest.java b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/GraphInferenceHighlightingTest.java
index b24ba27285bd..7d7f252fb547 100644
--- a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/GraphInferenceHighlightingTest.java
+++ b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/GraphInferenceHighlightingTest.java
@@ -495,6 +495,10 @@ public class GraphInferenceHighlightingTest extends LightDaemonAnalyzerTestCase
     doTest();
   }
 
+  public void testRecursiveTypeWithCapture() throws Exception {
+    doTest();
+  }
+
   private void doTest() throws Exception {
     doTest(false);
   }