YAML: Fix printing doubles a blank line before a comment

[sosukesuzuki]

Fixes #9130

Printing YAML comments be seem still unstable. I will create Issues after this PR is merged. But I think this is enough to solve the regression.

• I’ve added tests to confirm my change works.
• (If changing the API or CLI) I’ve documented the changes I’ve made (in the docs/ directory)
• (If the change is user-facing) I’ve added my changes to changelog_unreleased/*/pr-XXXX.md file following changelog_unreleased/TEMPLATE.md.
• I’ve read the contributing guidelines.

✨Try the playground for this PR✨

[fisker]

Prettier pr-9143
Playground link

--parser yaml

Input:

-  - a

   # - b

   # - c
   
   - e

-  - a

   # - b

   # - c

Output:

- - a

  # - b

  # - c

  - e

- - a
  # - b             <--  Missing line break before

  # - c

[sosukesuzuki]

@fisker This is a not regression because happens on 2.0.5:

(Sorry for console written in Japanese)

[fisker]

No, but I mean to fix both of them in #8356

Prettier pr-8356
Playground link

--parser yaml

Input:

-  - a

   # - b

   # - c
   
   - e

-  - a

   # - b

   # - c

Output:

- - a

  # - b

  # - c

  - e

- - a

  # - b


  # - c

[fisker]

Maybe add sequenceItem will do.

[sosukesuzuki]

@fisker Should we fix #9143 (comment) on this PR?

[alexander-akait]

@sosukesuzuki I think if it will be easy, let's do it here 😄

[fisker]

I think we should fix it, otherwise it will be v2.1.2 regression 😄

[fisker]

This one seems unreleated, but ugly

Prettier pr-9143
Playground link

--parser yaml

Input:

- a

  # a.commnent

- b
  # b.commnent

- c
  # c.commnent

Output:

- a


  # a.commnent
- b

  # b.commnent
- c
  # c.commnent

[sosukesuzuki]

YAML comment printing seems to have a lot of problems. To be honest, I want to solve the regression only and do patch release as soon as possible... After release, I'll look into those problems. Or, if you already have ideas to solve these, please commit to this branch of mine.

[sosukesuzuki]

@fisker Thank you!!

[fisker]

This is strange!!!

Prettier pr-9143
Playground link

--parser yaml

Input:

foo:
  # comment
bar:
  # comment

Output:

foo:
  # comment
bar:
  # comment

Prettier pr-9143
Playground link

--parser yaml

Input:

foo:
  # comment
barr:
  # comment

Output:

foo:
# comment   <---  this comment didn't indent, next key is `barr`
barr:
  # comment

[fisker]

Ah, seems attaching logic issue. I'll open an issue in the parser.

[fisker]

Issue in yaml-unist-parser prettier/yaml-unist-parser#275

[alexander-akait]

@fisker so can we merge this?

[fisker]

I think so.