# devopsgym / testgen__fasterxml__jackson-databind-4426

- taskset: [devopsgym](https://harnessreport.com/tasks/devopsgym.md)
- difficulty: hard
- category: test-generation
- language: 
- runnable from the site: no
- agent timeout: 3000s

## Results by harness

_none yet_

## Instruction

```
The following text contains a user issue (in <issue/> brackets) posted at a repository. Further, you are provided with file contents of several files in the repository that contain relevant code (in <code> brackets). It may be necessary to use code from third party dependencies or files not contained in the attached documents however. Your task is to identify the issue and implement a test case that verifies a proposed solution to this issue. More details at the end of this text.
<issue>
      If I have `ParameterNamesModule` and this data class:
```
public class Data {
  private final String foo;
  private final Integer bar;

  @JsonCreator(mode = JsonCreator.Mode.DELEGATING)
  static Data fromBuilder(Builder builder) {
    return new Data(builder.foo, builder.bar);
  }

  private Data(String foo, Integer bar) {
    this.foo = foo;
    this.bar = bar;
  }

  public String getFoo() {
    return foo;
  }

  public Integer getBar() {
    return bar;
  }

  public static class Builder {
    private String foo;
    private Integer bar;

    @JsonProperty("foo")
    public Builder foo(String foo) {
      this.foo = foo;
      return this;
    }

    @JsonProperty("bar")
    public Builder bar(Integer bar) {
      this.bar = bar;
      return this;
    }

    public Data build() {
      return Data.fromBuilder(this);
    }
  }
}
```

Then running `objectMapper.getSerializationConfig().introspect(/* Data type */);` will return a `BeanDescription` that includes `builder` as a property.  

This happens because with `ParameterNamesModule` we are able to infer the name of the `JsonCreator` parameter [here](https://github.com/FasterXML/jackson-databind/blob/master/src/main/java/com/fasterxml/jackson/databind/introspect/POJOPropertiesCollector.java#L451) and when we are, we include this parameter in the properties.

I think [here](https://github.com/FasterXML/jackson-databind/blob/master/src/main/java/com/fasterxml/jackson/databind/introspect/POJOPropertiesCollector.java#L438) we should be checking if the creator factory is a delegating kind that takes a complex value as an input. If maintainers of this repo agree, I will file a PR with the fix.

</issue>
Please generate test cases that check whether an implemented solution resolves the issue of the user (at the top, within <issue/> brackets).
You may apply changes to several files.
Apply as much reasoning as you please and see necessary.
Make sure to implement only test cases and don't try to fix the issue itself.
You are not allowed to read git history.
```
---
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