## Summary
This is causing some cyclic dependencies issues for me, because these
can be used in virtually _any_ crate (like `uv-install-wheel`), which
then means that all of `uv-configuration` becomes a dependency, etc. I
think this should be a leaf crate so that we can safely depend on it
anywhere.
This fixes a regression from 0.8.0 from
https://github.com/astral-sh/uv/pull/7934 and follows
https://github.com/astral-sh/uv/pull/15059
The regression is from [this
change](https://github.com/astral-sh/uv/pull/7934/files#diff-c7a660ac39628d5e12f388b0cacc7360affa3d7bb21191184d7ee78489675e83),
which was made because we'd otherwise (with the other changes in that
pull request) _filter out_ managed Python interpreters found in virtual
environments.
When `--system` is used we'll convert the default Python preference of
`managed` to `system` which avoids things like `uv pip install --system`
targeting a managed Python installation.
The basic test is
```
uv python install
uv pip install --system anyio
```
Prior to this change, we'd read a managed interpreter from our managed
installation directory and target that. After this change, without
#15059, we'd read a managed interpreter from the PATH and target that.
Both of those experiences are bad, because the managed interpreters are
marked as externally managed. After this change, with #15059, we
properly target the system interpreter.
Since we use `system` instead of `only-system`, if there is not a system
interpreter we'll still retain our existing behavior and use a managed
interpreter. This should limit breakage from the change. Given the
source of the regression, we could probably use `only-system` here. I
don't feel strongly. I think the main benefit of doing so would be that
we'd omit the check for managed installations in error messages when an
interpreter cannot be found?
We can't really add test coverage here because the test suite always has
externally managed interpreters :)
I think this would give us better hygiene than a global flag. It makes
it easier for users to opt-in to overlapping features, such as Python
upgrades and Python bin installations and to disable warnings for
preview mode without opting in to a bunch of other features. In general,
I want to reduce the burden for putting something under preview.
The `--preview` and `--no-preview` flags are retained as global
overrides. A new `--preview-features` option is added which accepts
comma separated features or can be passed multiple times, e.g.,
`--preview-features add-bounds,pylock`. There's a `UV_PREVIEW_FEATURES`
environment variable for that option (I'm not sure if we should overload
`UV_PREVIEW`, but could be convinced).
> NOTE: The PRs that were merged into this feature branch have all been
independently reviewed. But it's also useful to see all of the changes
in their final form. I've added comments to significant changes
throughout the PR to aid discussion.
This PR introduces transparent Python version upgrades to uv, allowing
for a smoother experience when upgrading to new patch versions.
Previously, upgrading Python patch versions required manual updates to
each virtual environment. Now, virtual environments can transparently
upgrade to newer patch versions.
Due to significant changes in how uv installs and executes managed
Python executables, this functionality is initially available behind a
`--preview` flag. Once an installation has been made upgradeable through
`--preview`, subsequent operations (like `uv venv -p 3.10` or patch
upgrades) will work without requiring the flag again. This is
accomplished by checking for the existence of a minor version symlink
directory (or junction on Windows).
### Features
* New `uv python upgrade` command to upgrade installed Python versions
to the latest available patch release:
```
# Upgrade specific minor version
uv python upgrade 3.12 --preview
# Upgrade all installed minor versions
uv python upgrade --preview
```
* Transparent upgrades also occur when installing newer patch versions:
```
uv python install 3.10.8 --preview
# Automatically upgrades existing 3.10 environments
uv python install 3.10.18
```
* Support for transparently upgradeable Python `bin` installations via
`--preview` flag
```
uv python install 3.13 --preview
# Automatically upgrades the `bin` installation if there is a newer patch version available
uv python upgrade 3.13 --preview
```
* Virtual environments can still be tied to a patch version if desired
(ignoring patch upgrades):
```
uv venv -p 3.10.8
```
### Implementation
Transparent upgrades are implemented using:
* Minor version symlink directories (Unix) or junctions (Windows)
* On Windows, trampolines simulate paths with junctions
* Symlink directory naming follows Python build standalone format: e.g.,
`cpython-3.10-macos-aarch64-none`
* Upgrades are scoped to the minor version key (as represented in the
naming format: implementation-minor version+variant-os-arch-libc)
* If the context does not provide a patch version request and the
interpreter is from a managed CPython installation, the `Interpreter`
used by `uv python run` will use the full symlink directory executable
path when available, enabling transparently upgradeable environments
created with the `venv` module (`uv run python -m venv`)
New types:
* `PythonMinorVersionLink`: in a sense, the core type for this PR, this
is a representation of a minor version symlink directory (or junction on
Windows) that points to the highest installed managed CPython patch
version for a minor version key.
* `PythonInstallationMinorVersionKey`: provides a view into a
`PythonInstallationKey` that excludes the patch and prerelease. This is
used for grouping installations by minor version key (e.g., to find the
highest available patch installation for that minor version key) and for
minor version directory naming.
### Compatibility
* Supports virtual environments created with:
* `uv venv`
* `uv run python -m venv` (using managed Python that was installed or
upgraded with `--preview`)
* Virtual environments created within these environments
* Existing virtual environments from before these changes continue to
work but aren't transparently upgradeable without being recreated
* Supports both standard Python (`python3.10`) and freethreaded Python
(`python3.10t`)
* Support for transparently upgrades is currently only available for
managed CPython installations
Closes#7287Closes#7325Closes#7892Closes#9031Closes#12977
---------
Co-authored-by: Zanie Blue <contact@zanie.dev>
Instead of always using all available threads for bytecode compilation,
respect `UV_CONCURRENT_INSTALLS`, so the parallelism is configurable
instead of hardcoded. We reuse the install limit since bytecode
compilation only runs after install.
Whew this is a lot.
The user-facing changes are:
- `uv toolchain` to `uv python` e.g. `uv python find`, `uv python
install`, ...
- `UV_TOOLCHAIN_DIR` to` UV_PYTHON_INSTALL_DIR`
- `<UV_STATE_DIR>/toolchains` to `<UV_STATE_DIR>/python` (with
[automatic
migration](https://github.com/astral-sh/uv/pull/4735/files#r1663029330))
- User-facing messages no longer refer to toolchains, instead using
"Python", "Python versions" or "Python installations"
The internal changes are:
- `uv-toolchain` crate to `uv-python`
- `Toolchain` no longer referenced in type names
- Dropped unused `SystemPython` type (previously replaced)
- Clarified the type names for "managed Python installations"
- (more little things)
Restores the `PythonEnvironment::find` API which was removed a while
back in favor of `Toolchain::find`. As mentioned in #4416, I'm
attempting to separate the case where you want an active environment
from the case where you want an installed toolchain in order to create
environments.
I wanted to drop `EnvironmentPreference` from `Toolchain::find` and just
have us consistently consider (or not consider) virtual environments
when discovering toolchains for creating environments. Unfortunately
this caused a few things to break so I reverted that change and will
explore it separately. Because I was exploring that change, there are
some minor changes to the `Toolchain` API here.
Adds support for the toolchain discovery preferences outlined in
https://github.com/astral-sh/uv/issues/4198 but we don't expose this to
users yet, I'll do that next to make it easier to review.
I've made some refactors in the toolchain discovery implementation to
enable this behavior and move us towards clearer abstractions. There's
still remaining work here, but I'd prefer tackle things in follow-ups
instead of expanding this pull request. I plan on opening a couple
before merging this.
I'd like to shift the public toolchain API to focus on discovering
either an **environment** or a **toolchain**. The first would be used by
commands that operate on an environment, while the latter would be used
by commands that just need an interpreter to create environments. I
haven't changed this here, but some of the refactors are in preparation
for supporting this idea.
In brief:
- We now allow different ordering of installed toolchain discovery based
on a `ToolchainPreference` type. This is the type we will expose to
users.
- `SystemPython` was changed into an `EnvironmentPreference` which is
used to determine if we should prefer virtual or system Python
environments.
- We drop the whole `ToolchainSources` selection concept, it was
confusing and the error messages from it were awkward. Most of the
functionality is now captured by the preference enums, but you can't do
things like "only find a toolchain from the parent interpreter" as
easily anymore.
Extends #4120
Part of #2607
There should be no behavior changes here. Restructures the discovery API
to be focused on a toolchain first perspective in preparation for
exposing a `find_or_fetch` method for toolchains in
https://github.com/astral-sh/uv/pull/4138.
The architecture of uv does not necessarily match that of the python
interpreter (#2326). In cross compiling/testing scenarios the operating
system can also mismatch. To solve this, we move arch and os detection
to python, vendoring the relevant pypa/packaging code, preventing
mismatches between what the python interpreter was compiled for and what
uv was compiled for.
To make the scripts more manageable, they are now a directory in a
tempdir and we run them with `python -m` . I've simplified the
pypa/packaging code since we're still building the tags in rust. A
`Platform` is now instantiated by querying the python interpreter for
its platform. The pypa/packaging files are copied verbatim for easier
updates except a `lru_cache()` python 3.7 backport.
Error handling is done by a `"result": "success|error"` field that allow
passing error details to rust:
```console
$ uv venv --no-cache
× Can't use Python at `/home/konsti/projects/uv/.venv/bin/python3`
╰─▶ Unknown operation system `linux`
```
I've used the [maturin sysconfig
collection](855f6d2cb1/sysconfig)
as reference. I'm unsure how to test these changes across the wide
variety of platforms.
Fixes#2326
Add a `--compile` option to `pip install` and `pip sync`.
I chose to implement this as a separate pass over the entire venv. If we
wanted to compile during installation, we'd have to make sure that
writing is exclusive, to avoid concurrent processes writing broken
`.pyc` files. Additionally, this ensures that the entire site-packages
are bytecode compiled, even if there are packages that aren't from this
`uv` invocation. The disadvantage is that we do not update RECORD and
rely on this comment from [PEP 491](https://peps.python.org/pep-0491/):
> Uninstallers should be smart enough to remove .pyc even if it is not
mentioned in RECORD.
If this is a problem we can change it to run during installation and
write RECORD entries.
Internally, this is implemented as an async work-stealing subprocess
worker pool. The producer is a directory traversal over site-packages,
sending each `.py` file to a bounded async FIFO queue/channel. Each
worker has a long-running python process. It pops the queue to get a
single path (or exists if the channel is closed), then sends it to
stdin, waits until it's informed that the compilation is done through a
line on stdout, and repeat. This is fast, e.g. installing `jupyter
plotly` on Python 3.12 it processes 15876 files in 319ms with 32 threads
(vs. 3.8s with a single core). The python processes internally calls
`compileall.compile_file`, the same as pip.
Like pip, we ignore and silence all compilation errors
(https://github.com/astral-sh/uv/issues/1559). There is a 10s timeout to
handle the case when the workers got stuck. For the reviewers, please
check if i missed any spots where we could deadlock, this is the hardest
part of this PR.
I've added `uv-dev compile <dir>` and `uv-dev clear-compile <dir>`
commands, mainly for my own benchmarking. I don't want to expose them in
`uv`, they almost certainly not the correct workflow and we don't want
to support them.
Fixes#1788Closes#1559Closes#1928
Charlie Marsh
Zanie Blue
John Mumm
konsti