Added missing transformation of NullableType (#453)

Author: vojtechhabarta

typescript-generator-core/src/main/java/cz/habarta/typescript/generator/TsType.java

@@ -421,6 +421,10 @@ public static TsType transformTsType(Context context, TsType tsType, Transformer
             final TsType.OptionalType optionalType = (TsType.OptionalType) type;
             return new TsType.OptionalType(transformTsType(context, optionalType.type, transformer));
         }
+        if (type instanceof TsType.NullableType) {
+            final TsType.NullableType nullableType = (TsType.NullableType) type;
+            return new TsType.NullableType(transformTsType(context, nullableType.type, transformer));
+        }
         if (type instanceof TsType.BasicArrayType) {
             final TsType.BasicArrayType basicArrayType = (TsType.BasicArrayType) type;
             return new TsType.BasicArrayType(transformTsType(context, basicArrayType.elementType, transformer));

typescript-generator-core/src/test/java/cz/habarta/typescript/generator/NullabilityTest.java

@@ -1,6 +1,7 @@
 
 package cz.habarta.typescript.generator;
 
+import java.util.Date;
 import java.util.List;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.junit.Assert;
@@ -127,4 +128,18 @@ public void testNullableAnnotationTarget() {
         new TypeScriptGenerator(settings).generateTypeScript(Input.from(A.class));
     }
 
+    @Test
+    public void testDate() {
+        final Settings settings = TestUtils.settings();
+        settings.nullableAnnotations.add(Nullable.class);
+        settings.nullabilityDefinition = NullabilityDefinition.nullAndUndefinedUnion;
+        settings.mapDate = DateMapping.asString;
+        final String output = new TypeScriptGenerator(settings).generateTypeScript(Input.from(ClassWithDate.class));
+        Assert.assertTrue(output.contains("date?: Nullable<DateAsString>"));
+    }
+
+    private static class ClassWithDate {
+        public @Nullable Date date;
+    }
+
 }