New J2K: retrieve constructor call return type correctly

#KT-33431 fixed

nj2k/src/org/jetbrains/kotlin/nj2k/symbols/JKMethodSymbol.kt

@@ -9,13 +9,12 @@ import com.intellij.psi.PsiMethod
 import com.intellij.psi.PsiReference
 import org.jetbrains.kotlin.asJava.elements.KtLightMethod
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.idea.refactoring.fqName.getKotlinFqName
+import org.jetbrains.kotlin.j2k.ast.Nullability
 import org.jetbrains.kotlin.nj2k.JKSymbolProvider
-import org.jetbrains.kotlin.nj2k.tree.JKClass
+import org.jetbrains.kotlin.nj2k.tree.*
-import org.jetbrains.kotlin.nj2k.tree.JKMethod
-import org.jetbrains.kotlin.nj2k.tree.JKType
 import org.jetbrains.kotlin.nj2k.tree.impl.JKClassTypeImpl
 import org.jetbrains.kotlin.nj2k.tree.impl.JKNoTypeImpl
-import org.jetbrains.kotlin.nj2k.tree.toJK
 import org.jetbrains.kotlin.psi.KtFunction
 import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
@@ -49,7 +48,8 @@ class JKMultiverseMethodSymbol(
     override val parameterTypes: List<JKType>
         get() = target.parameterList.parameters.map { it.type.toJK(symbolProvider) }
     override val returnType: JKType
-        get() = target.returnType!!.toJK(symbolProvider)
+        get() = target.returnType?.toJK(symbolProvider) // null for constructor call
+            ?: symbolProvider.provideClassSymbol(target.getKotlinFqName()!!).asType(Nullability.NotNull)
 
     override val fqName: String
         get() {

nj2k/testData/newJ2k/function/referenceToConstructor.external.java

@@ -0,0 +1,7 @@
+public class Person {
+    private final String name;
+
+    public Person(String name) {
+        this.name = name;
+    }
+}

nj2k/testData/newJ2k/function/referenceToConstructor.java

@@ -0,0 +1,12 @@
+// RUNTIME_WITH_FULL_JDK
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class TestLambda {
+    public static void main(String[] args) {
+        List<String> names = Arrays.asList("A", "B");
+        List<Person> people = names.stream().map(Person::new).collect(Collectors.toList());
+    }
+}

nj2k/testData/newJ2k/function/referenceToConstructor.kt

@@ -0,0 +1,10 @@
+import java.util.Arrays
+import java.util.stream.Collectors
+
+object TestLambda {
+    @JvmStatic
+    fun main(args: Array<String>) {
+        val names: List<String> = Arrays.asList("A", "B")
+        val people: List<Person?> = names.stream().map { name: String -> Person(name) }.collect(Collectors.toList())
+    }
+}

nj2k/tests/org/jetbrains/kotlin/nj2k/NewJavaToKotlinConverterSingleFileTestGenerated.java

@@ -2443,6 +2443,11 @@ public class NewJavaToKotlinConverterSingleFileTestGenerated extends AbstractNew
             runTest("nj2k/testData/newJ2k/function/public.java");
         }
 
+        @TestMetadata("referenceToConstructor.java")
+        public void testReferenceToConstructor() throws Exception {
+            runTest("nj2k/testData/newJ2k/function/referenceToConstructor.java");
+        }
+
         @TestMetadata("synchronizedMethod.java")
         public void testSynchronizedMethod() throws Exception {
             runTest("nj2k/testData/newJ2k/function/synchronizedMethod.java");