Previously, we'd use the `--reinstall` flag to determine if we should
replace existing Python executables in the bin directory during an
install. There are a few problems with this:
- We replace executables we don't manage
- We can replace executables from other uv Python installations during
reinstall (surprising)
- We don't do the "right" thing when installing patch versions e.g.
installing `3.12.4` then `3.12.6` would fail without the reinstall flag
In `uv tool`, we have separate `--force` and `--reinstall` concepts.
Here we separate the flags (`--force` was previously just a
`--reinstall` alias) and add inspection of the existing executables to
inform a decision on replacement.
In brief, we will:
- Replace any executables with `--force`
- Replace executables for the same installation with `--reinstall`
- Replace executables for an older patch version by default
Incorporating #8637 into #8458
- Adds `python-managed` feature selection to Windows CI for `python
install` tests
- Adds trampoline sniffing utilities to `uv-trampoline-builder`
- Uses a trampoline to install Python executables into the `PATH` on
Windows
Updates `uv python install` to link `python3.x` in the executable
directory (i.e., `~/.local/bin`) to the the managed interpreter path.
Includes
- #8569
- #8571
Remaining work
- #8663
- #8650
- Add an opt-out setting and flag
- Update documentation
## Summary
This PR declares and documents all environment variables that are used
in one way or another in `uv`, either internally, or externally, or
transitively under a common struct.
I think over time as uv has grown there's been many environment
variables introduced. Its harder to know which ones exists, which ones
are missing, what they're used for, or where are they used across the
code. The docs only documents a handful of them, for others you'd have
to dive into the code and inspect across crates to know which crates
they're used on or where they're relevant.
This PR is a starting attempt to unify them, make it easier to discover
which ones we have, and maybe unlock future posibilities in automating
generating documentation for them.
I think we can split out into multiple structs later to better organize,
but given the high influx of PR's and possibly new environment variables
introduced/re-used, it would be hard to try to organize them all now
into their proper namespaced struct while this is all happening given
merge conflicts and/or keeping up to date.
I don't think this has any impact on performance as they all should
still be inlined, although it may affect local build times on changes to
the environment vars as more crates would likely need a rebuild. Lastly,
some of them are declared but not used in the code, for example those in
`build.rs`. I left them declared because I still think it's useful to at
least have a reference.
Did I miss any? Are their initial docs cohesive?
Note, `uv-static` is a terrible name for a new crate, thoughts? Others
considered `uv-vars`, `uv-consts`.
## Test Plan
Existing tests
As we support more complex Python discovery behaviors such as:
- #7431
- #7335
- #7300
`Any` is no longer accurate, we actually are looking for a reasonable
default Python version to use which may exclude the first one we find.
Separately, we need the idea of `Any` to improve behavior when listing
versions (e.g., #7286) where we do actually want to match _any_ Python
version. As a first step, we'll rename `Any` to `Default`. Then, we'll
introduce a new `Any` that actually behaves as we'd expect.
As described in #4242, we're currently incorrectly downloading glibc
python-build-standalone on musl target, but we also can't fix this by
using musl python-build-standalone on musl targets since the musl builds
are effectively broken.
We reintroduce the libc detection previously removed in #2381, using it
to detect which libc is the current one before we have a python
interpreter. I changed the strategy a big to support an empty `PATH`
which we use in the tests.
For simplicity, i've decided to just filter out the musl
python-build-standalone archives from the list of available archive,
given this is temporary. This means we show the same error message as if
we don't have a build for the platform. We could also add a dedicated
error message for musl.
Fixes#4242
## Test Plan
Tested manually.
On my ubuntu host, python downloads continue to pass:
```
target/x86_64-unknown-linux-musl/debug/uv python install
```
On alpine, we fail:
```
$ docker run -it --rm -v .:/io alpine /io/target/x86_64-unknown-linux-musl/debug/uv python install
Searching for Python installations
error: No download found for request: cpython-any-linux-x86_64-musl
```
## Summary
Resolves#5139
`PythonInstallationKey` was sorted as a string, which caused `3.8` to
appear before `3.11`. This update changes the sorting of
`PythonInstallationKey` to be a descending order by version.
## Test Plan
```sh
$ cargo run -- python install 3.8 3.12
$ cargo run -- tool run -v python -V
DEBUG uv 0.2.25
warning: `uv tool run` is experimental and may change without warning.
DEBUG Searching for Python interpreter in managed installations, system path, or `py` launcher
DEBUG Searching for managed installations at `C:\Users\xx\AppData\Roaming\uv\data\python`
DEBUG Found managed Python `cpython-3.12.3-windows-x86_64-none`
DEBUG Found cpython 3.12.3 at `C:\Users\xx\AppData\Roaming\uv\data\python\cpython-3.12.3-windows-x86_64-none\install\python.exe` (managed installations)
DEBUG Using request timeout of 30s
DEBUG Using request timeout of 30s
DEBUG Acquired lock for `C:\Users\nigel\AppData\Roaming\uv\data\tools`
DEBUG Using existing environment for tool `httpx`: C:\Users\xx\AppData\Roaming\uv\data\tools\httpx
DEBUG Using existing tool `httpx`
DEBUG Running `httpx -v`
```
## Summary
Resolves#4834
## Test Plan
```sh
# 3.12.3 is a `install_only` archive
$ cargo run -- python install --preview --force 3.12.3
# 3.9.4 has only `full` archive
$ cargo run -- python install --preview --force 3.9.4
```
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)