`org.openrewrite.yaml.MergeYaml` is not respecting the current indentation of the list

[johnsterken]

When merging into an existing list with no indentation, the modified entry will be indented, causing the new list to be invalid

What version of OpenRewrite are you using?

I am using

• OpenRewrite v8.47.1
• Maven plugin v6.2.0

What is the smallest, simplest way to reproduce the problem?

I wrote a unit test to reproduce the issue

class MergeYamlTest implements RewriteTest {
    ...
    @Test
    void mergeListRespectIndentation() {
        rewriteRun(spec ->
            spec.recipe(new MergeYaml(
              "$",
              //language=yaml
              """
                widget:
                  list:
                  - item 2
                """,
              false,
              null,
              null,
              null,
              null
            )),
          yaml(
            """
              widget:
                list:
                - item 1
              """,
            """
              widget:
                list:
                - item 1
                - item 2
              """
          )
        );
    }
    ...
}

What did you expect to see?

 widget:
   list:
   - item 1
   - item 2

What did you see instead?

widget:
    list:
    - item 1
      - item 2

[timtebeek]

hi John; indeed looks like we're not handling appending to non-indented list items correctly. Thanks for the runnable example!
The suggested usage for that recipe is slightly different, but even then I'm seeing similar issues with indentation on item 2.

@Test
void mergeListRespectIndentation() {
    rewriteRun(spec ->
        spec.recipe(new MergeYaml(
          "$.widget.list",
          //language=yaml
          """
            - item 2
            """,
          false,
          null,
          null,
          null,
          null
        )),
      yaml(
        """
          widget:
            list:
            - item 1
          """,
        """
          widget:
            list:
            - item 1
            - item 2
          """ // in reality item 2 is shifted to the right by two spaces :/
      )
    );
}