support updating all packages when using --prerelease

[DetachHead]

Is your feature/enhancement proposal related to a problem? Please describe.

i have some dependencies where i want to resolve prerelease versions, but i also don't want them to be reverted to release versions when running pdm update to bump all my dependencies.

currently to do this, i need to run two commands:

pdm update --prerelease foo bar  # update the dependencies i want prereleases for
pdm update  # update everything else

Describe the solution you'd like

maybe it can be specified in the pyproject.toml:

[tool.pdm.dev-dependencies]
dev = [
    {dependency = "foo>=1.0", prerelease=true},
    {dependency = "bar>=1.0", prerelease=true},
    "baz>=2.1",
]

that way, all i have to do is run pdm update

[frostming]

A little trick, use prerelease versions in the version specifier:

dev = [
    "foo>=1.0a0",  # allows prereleases to be locked
    "bar>=1.0a0",
    "baz>=2.1",
]

We won't support a table as dependency specification, unless there is a standard for this(looking forward to PEP 735)

[DetachHead]

in my case, i still want to support versions older than the prerelease for prod dependencies, but in the dev environment i want it to resolve to the prerelease versions

[frostming]

in my case, i still want to support versions older than the prerelease for prod dependencies, but in the dev environment i want it to resolve to the prerelease versions

Sorry I don't get your point, you know there is only one pin for each package, so what version do you want to resolve to?

[DetachHead]

sorry i probably didn't explain my use case very well. basically, i want a pre-release version to be pinned, while still supporting release versions that are older. i maintain a pytest plugin that supports the following versions:

dependencies = [
    "pytest<9,>=7"
]

pytest 8.0 has not been released yet, but i want pdm to pin it to 8.0.0rc1 in my dev environment. however i still want users of my plugin to not have to use a prerelease version of pytest, which is why i can't just specify the prerelease version in the dependencies.

i shouldn't have used dev dependencies in the OP, because i think this issue is only relevant for prod dependencies

[frostming]

dependencies = [
    "pytest<9,>=7"
]

Okay, so you want to pin a rc version in your development environment but the end users who install the library should never use a prerelease, right?

[DetachHead]

yeah

[frostming]

What you actually need is the ability to remember what packages allow prereleases in the resolution result. Unfortunately we don't support this for now and you have to specify --prerelease every time.