feat: install uv (#198)

Author: joshuarli

README.md

@@ -153,6 +153,59 @@ export VIRTUAL_ENV="${PWD}/.venv"
 PATH_add "${PWD}/.venv/bin"
 ```
 
+if using uv:
+
+`[reporoot]/devenv/sync.py`
+```py
+from devenv.lib import uv
+
+def main(context: dict[str, str]) -> int:
+    reporoot = context["reporoot"]
+    cfg = config.get_repo(reporoot)
+
+    uv.install(
+        cfg["uv"]["version"],
+        cfg["uv"][constants.SYSTEM_MACHINE],
+        cfg["uv"][f"{constants.SYSTEM_MACHINE}_sha256"],
+        reporoot,
+    )
+
+    # reporoot/.venv is the default venv location
+    print(f"syncing .venv ...")
+    proc.run(("uv", "sync", "--frozen", "--quiet"))
+
+    return 0
+```
+
+`[reporoot]/devenv/config.ini`
+```ini
+[uv]
+darwin_arm64 = https://github.com/astral-sh/uv/releases/download/0.7.21/uv-aarch64-apple-darwin.tar.gz
+darwin_arm64_sha256 = c73af7a4e0bcea9b5b593a0c7e5c025ee78d8be3f7cd60bfeadc8614a16c92ef
+darwin_x86_64 = https://github.com/astral-sh/uv/releases/download/0.7.21/uv-x86_64-apple-darwin.tar.gz
+darwin_x86_64_sha256 = f8a9b4f4a80a44653344d36b53e148134176e8f7cc99f8e823676a57c884595e
+linux_arm64 = https://github.com/astral-sh/uv/releases/download/0.7.21/uv-aarch64-unknown-linux-gnu.tar.gz
+linux_arm64_sha256 = 1dae18211605b9d00767d913da5108aea50200a88372bf8a2e1f56abdbe509f0
+linux_x86_64 = https://github.com/astral-sh/uv/releases/download/0.7.21/uv-x86_64-unknown-linux-gnu.tar.gz
+linux_x86_64_sha256 = ca3e8898adfce5fcc891d393a079013fa4bd0d9636cef11aded8a7485bcba312
+# used for autoupdate
+version = 0.7.21
+```
+
+`[reporoot]/.python-version`
+```
+3.13.3
+```
+
+`[reporoot]/pyproject.toml`
+```
+[project]
+name = "foo"
+version = "0.0.0"
+```
+
+or classic pip:
+
 `[reporoot]/devenv/sync.py`
 ```py
 from devenv.lib import config, venv

devenv/lib/uv.py

@@ -0,0 +1,56 @@
+from __future__ import annotations
+
+import os
+import shutil
+import tempfile
+
+from devenv.lib import archive
+from devenv.lib import fs
+from devenv.lib import proc
+
+
+def _install(url: str, sha256: str, into: str) -> None:
+    with tempfile.TemporaryDirectory(dir=into) as tmpd:
+        archive_file = archive.download(url, sha256, dest=f"{tmpd}/download")
+        archive.unpack(archive_file, tmpd, perform_strip1=True)
+
+        # the archive was atomically placed into tmpd so
+        # these are on the same fs and can be atomically moved too
+        os.replace(f"{tmpd}/uv", f"{into}/uv")
+        os.replace(f"{tmpd}/uvx", f"{into}/uvx")
+
+
+def uninstall(binroot: str) -> None:
+    for fp in (f"{binroot}/uv", f"{binroot}/uvx"):
+        try:
+            os.remove(fp)
+        except FileNotFoundError:
+            # it's better to do this than to guard with
+            # os.path.exists(fp) because if it's an invalid or circular
+            # symlink the result'll be False!
+            pass
+
+
+def _version(binpath: str) -> str:
+    stdout = proc.run((binpath, "--version"), stdout=True)
+    # uv 0.7.21 (77c771c7f 2025-07-14)
+    return stdout.split()[1]
+
+
+def install(version: str, url: str, sha256: str, reporoot: str) -> None:
+    binroot = fs.ensure_binroot(reporoot)
+    binpath = f"{binroot}/uv"
+
+    if shutil.which("uv", path=binroot) == binpath:
+        installed_version = _version(binpath)
+        if version == installed_version:
+            return
+        print(f"installed uv {installed_version} is unexpected!")
+
+    print(f"installing uv {version}...")
+    uninstall(binroot)
+    _install(url, sha256, binroot)
+
+    installed_version = _version(binpath)
+    if version != installed_version:
+        raise SystemExit("Failed to install uv {version}!")