Unwrapped lists cannot be deserialized when using JsonTypeInfo.As.EXISTING_PROPERTY

[vhschlenker]

If the UnwrappedPolymorphicList490Test is changed to the following:

package com.fasterxml.jackson.dataformat.xml.lists;

import java.util.*;

import org.junit.jupiter.api.Test;

import com.fasterxml.jackson.annotation.*;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;
import com.fasterxml.jackson.dataformat.xml.XmlTestUtil;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;

public class UnwrappedPolymorphicList490Test extends XmlTestUtil
{
    @JsonTypeInfo(
            use = JsonTypeInfo.Id.NAME,
+           include = JsonTypeInfo.As.EXISTING_PROPERTY,
            property = "type")
    @JsonSubTypes({
            @JsonSubTypes.Type(value = MyType490.class, name = "myType"),
    })
    interface IMyType490 { }

    static class MyType490 implements IMyType490 {
        public final String stringValue;
+       public final String type = "myType";
        public final Collection<String> typeNames;

        @JsonCreator
        public MyType490(
                @JsonProperty("stringValue") String stringValue,
                @JsonProperty("typeNames") Collection<String> typeNames) {
            this.stringValue = stringValue;
            this.typeNames = typeNames;
        }
    }

    // [dataformat-xml#490]
    @Test
    public void testPolymorphicUnwrappedList490() throws Exception
    {
        XmlMapper xmlMapper = XmlMapper.builder()
                .defaultUseWrapper(false).build();

        List<String> typeNames = new ArrayList<>();
        typeNames.add("type1");
        typeNames.add("type2");
        MyType490 input = new MyType490("hello", typeNames);
        String doc = xmlMapper.writeValueAsString(input);
        IMyType490 result = xmlMapper.readValue(doc, IMyType490.class);        

        assertNotNull(result);
        assertEquals(MyType490.class, result.getClass());
        MyType490 typedResult = (MyType490) result;
        assertEquals(Arrays.asList("type1", "type2"), typedResult.typeNames);
    }
}

the deserialization breaks with this error:

com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of `java.util.ArrayList` (although at least one Creator exists): no String-argument constructor/factory method to deserialize from String value ('type1')
 at [Source: (StringReader); line: 1, column: 112] (through reference chain: com.fasterxml.jackson.dataformat.xml.lists.UnwrappedPolymorphicList490Test$MyType490["typeNames"])

Is that to be expected?

[cowtowncoder]

Same fix as for #762; will add test, mark as fixed.