Loading functions from superclasses before current to avoid heisenbug.

Added test with two supertypes.

 #KT-2776 in progress

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/resolver/JavaFunctionResolver.java

@@ -188,6 +188,11 @@ public final class JavaFunctionResolver {
     ) {
         final Set<FunctionDescriptor> functions = new HashSet<FunctionDescriptor>();
 
+        Set<SimpleFunctionDescriptor> functionsFromSupertypes = null;
+        if (owner instanceof ClassDescriptor) {
+            functionsFromSupertypes = getFunctionsFromSupertypes(methodName, owner);
+        }
+
         Set<SimpleFunctionDescriptor> functionsFromCurrent = Sets.newHashSet();
         for (PsiMethodWrapper method : namedMembers.getMethods()) {
             SimpleFunctionDescriptor function = resolveMethodToFunctionDescriptor(psiClass, method, scopeData, owner);
@@ -199,8 +204,6 @@ public final class JavaFunctionResolver {
         if (owner instanceof ClassDescriptor) {
             ClassDescriptor classDescriptor = (ClassDescriptor) owner;
 
-            Set<SimpleFunctionDescriptor> functionsFromSupertypes = getFunctionsFromSupertypes(methodName, owner);
-
             OverrideResolver.generateOverridesInFunctionGroup(methodName, functionsFromSupertypes, functionsFromCurrent, classDescriptor,
                   new OverrideResolver.DescriptorSink() {
                       @Override

compiler/testData/loadJavaCustom/kotlinSignature/TwoSuperclassesInconsistentGenericTypes.java

@@ -0,0 +1,22 @@
+package test;
+
+import org.jetbrains.annotations.NotNull;
+import java.util.List;
+
+import jet.runtime.typeinfo.KotlinSignature;
+
+public interface TwoSuperclassesInconsistentGenericTypes {
+    @KotlinSignature("fun foo(): MutableList<String?>")
+    List<String> foo();
+
+    public interface Other {
+        @KotlinSignature("fun foo(): MutableList<String>?")
+        List<String> foo();
+    }
+
+    public class Sub implements TwoSuperclassesInconsistentGenericTypes, Other {
+        public List<String> foo() {
+            throw new UnsupportedOperationException();
+        }
+    }
+}

compiler/testData/loadJavaCustom/kotlinSignature/TwoSuperclassesInconsistentGenericTypes.txt

@@ -0,0 +1,12 @@
+namespace test
+
+public abstract trait test.TwoSuperclassesInconsistentGenericTypes : java.lang.Object {
+    public abstract fun foo(): jet.MutableList<jet.String?>
+    public abstract trait test.TwoSuperclassesInconsistentGenericTypes.Other : java.lang.Object {
+        public abstract fun foo(): jet.MutableList<jet.String>?
+    }
+    public open class test.TwoSuperclassesInconsistentGenericTypes.Sub : test.TwoSuperclassesInconsistentGenericTypes, test.TwoSuperclassesInconsistentGenericTypes.Other {
+        public final /*constructor*/ fun <init>(): test.TwoSuperclassesInconsistentGenericTypes.Sub
+        public open override /*2*/ fun foo(): jet.MutableList<jet.String?>
+    }
+}

compiler/tests/org/jetbrains/jet/jvm/compiler/LoadJavaCustomTest.java

@@ -84,6 +84,12 @@ public final class LoadJavaCustomTest extends KotlinTestWithEnvironment {
                PATH + "/" + getTestName(true) + ".java");
     }
 
+    public void testKotlinSignatureTwoSuperclassesInconsistentGenericTypes() throws Exception {
+        String dir = PATH + "/kotlinSignature/";
+        doTest(dir + "TwoSuperclassesInconsistentGenericTypes.txt",
+               dir + "TwoSuperclassesInconsistentGenericTypes.java");
+    }
+
     //TODO: move to LoadJavaTestGenerated when possible
     public void testEnum() throws Exception {
         String dir = PATH + "/enum";