From 4adc3db92c82327b5f7a86cdce49183fcb4447e9 Mon Sep 17 00:00:00 2001
From: anna <Anna.Kozlova@jetbrains.com>
Date: Mon, 17 Sep 2012 19:35:41 +0200
Subject: [PATCH] lambda: return type compatibility test

---
 .../src/com/intellij/psi/LambdaUtil.java      |  9 +++++-
 .../ReturnTypeCompatibility1.java             | 31 +++++++++++++++++++
 .../daemon/lambda/LambdaHighlightingTest.java |  4 +++
 3 files changed, 43 insertions(+), 1 deletion(-)
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/highlighting/ReturnTypeCompatibility1.java

diff --git a/java/java-psi-api/src/com/intellij/psi/LambdaUtil.java b/java/java-psi-api/src/com/intellij/psi/LambdaUtil.java
index 50b18b84baad..17fd89007daf 100644
--- a/java/java-psi-api/src/com/intellij/psi/LambdaUtil.java
+++ b/java/java-psi-api/src/com/intellij/psi/LambdaUtil.java
@@ -306,7 +306,14 @@ public class LambdaUtil {
   @Nullable
   private static PsiType getReturnType(PsiClass psiClass, MethodSignature methodSignature) {
     final PsiMethod method = getMethod(psiClass, methodSignature);
-    return method != null ? method.getReturnType() : null;
+    if (method != null) {
+      final PsiClass containingClass = method.getContainingClass();
+      if (containingClass == null) return null;
+      return TypeConversionUtil.getSuperClassSubstitutor(containingClass, psiClass, PsiSubstitutor.EMPTY).substitute(method.getReturnType());
+    }
+    else {
+      return null;
+    }
   }
 
   @Nullable
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/highlighting/ReturnTypeCompatibility1.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/highlighting/ReturnTypeCompatibility1.java
new file mode 100644
index 000000000000..d34d61ffad42
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/highlighting/ReturnTypeCompatibility1.java
@@ -0,0 +1,31 @@
+class Test {
+
+    interface I<A, B> {
+        B f(A a);
+    }
+
+    interface II<A, B> extends I<A,B> { }
+
+    static class Foo<A> {
+        boolean forAll(final I<A, Boolean> f) {
+            return false;
+        }
+
+        String forAll(final II<A, String> f) {
+            return "";
+        }
+
+        String forAll2(final II<A, String> f) {
+            return "";
+        }
+    }
+
+    void foo(Foo<String> as, final Foo<Character> ac) {
+        boolean b1 = as.forAll(s -> ac.forAll(c -> false));
+        String s1 = as.forAll(s -> ac.forAll(c -> ""));
+        <error descr="Incompatible types. Found: 'java.lang.String', required: 'boolean'">boolean b2 = as.forAll(s -> ac.forAll(c -> ""));</error>
+        String s2 = as.forAll2(s -> ac.forAll2(<error descr="Incompatible return type boolean in lambda expression">c -> false</error>));
+        boolean b3 = as.forAll((I<String, Boolean>)s -> ac.forAll((I<Character, Boolean>)<error descr="Incompatible return type String in lambda expression">c -> ""</error>));
+        String s3 = as.forAll((II<String, String>)s -> ac.forAll((II<Character, String>)<error descr="Incompatible return type boolean in lambda expression">c -> false</error>));
+    }
+}
diff --git a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/LambdaHighlightingTest.java b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/LambdaHighlightingTest.java
index 1899a5c0d118..46646b36afcd 100644
--- a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/LambdaHighlightingTest.java
+++ b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/LambdaHighlightingTest.java
@@ -100,6 +100,10 @@ public class LambdaHighlightingTest extends LightDaemonAnalyzerTestCase {
   public void testLambdaRawOrNot() throws Exception {
     doTest();
   }
+
+  public void testReturnTypeCompatibility1() throws Exception {
+    doTest();
+  }
   
   public void testNoInferenceResult() throws Exception {
     doTest();