uv does not respect position of comments in `pyproject.toml`

[notatallshaw]

uv 0.4.24

Maybe this is already reported but I couldn't find it.

Steps to reproduce:

1, uv init temp
2. cd temp
3. uv add requests
4. uv add whenever~=0.6.9
5. Edit project.dependencies in pyproject.toml from:

dependencies = [
    "requests>=2.32.3",
    "whenever~=0.6.9",
]

To:

dependencies = [
    "requests>=2.32.3", # Should not expect to be updated frequently
    "whenever~=0.6.9", # Pinned to 0.6 due to API not yet being stable
]

6. uv add uv zope
7. Check project.dependencies in pyproject.toml:

Actual output:

dependencies = [
    "requests>=2.32.3",
    "uv>=0.4.24",
    # Should not expect to be updated frequently
    "whenever~=0.6.9",
    "zope>=5.11",
     # Pinned to 0.6 due to API not yet being stable
]

Expected output:

dependencies = [
    "requests>=2.32.3", # Should not expect to be updated frequently
    "uv>=0.4.24",
    "whenever~=0.6.9", # Pinned to 0.6 due to API not yet being stable
    "zope>=5.11", 
]

Context:

I often leave comments in my pyproject.toml to explain why a particular dependency is pinned or given an upper bound.

I appreciate that comments are a hard problem when reading and writing toml, and there will always be edge cases where the user needs to manually update them (e.g. a requirement is removed), but I don't think this example is an edge case.

[charliermarsh]

I suppose that's a legitimate bug though end-of-line comments are my mortal enemy from working on the formatter and I don't know if I can work up the courage to fix it myself :)

[flyaroundme]

Tricky one. The fun thing is that the "current dependency line comment" in this case is becoming a next dependency prefix, so in case it is the comment on the last line it is becoming part of trailing, that's why it is in the end of the file after adding zope.
I am digging into it so feel free to assign on me, but most probably can send the fix more close to the end of the weekend, so I'm totally fine if somebody solves it beforehand