fix(uv): colocate the uv Python install dir with the ROCm CLI data dir

MANIFEST.md

@@ -681,6 +681,13 @@ manages, on the order of several GB per SDK version installed. It is removed by
 `rocm uninstall` unless `--keep-data` is passed, and its location can be
 overridden with `ROCM_CLI_UV_CACHE_DIR`.
 
+When a managed Python interpreter is needed, `uv python install` downloads a
+standalone CPython build. That download is also kept in the managed data
+directory (at `<data-dir>/uv-python`) rather than `uv`'s own default of
+`$HOME/.local/share/uv/python/`. It is removed by `rocm uninstall` unless
+`--keep-data` is passed, and its location can be overridden with
+`ROCM_CLI_UV_PYTHON_INSTALL_DIR`.
+
 ### Lemonade Embeddable Runtime
 
 When `rocm engines install lemonade` is run, the CLI downloads a prebuilt

apps/rocm/src/main.rs

@@ -42,7 +42,7 @@ use rocm_core::{
     read_tcp_stream_to_string, resolve_builtin_model_recipe, resolve_model_recipe,
     runtime_install_root_is_protected, runtime_path_is_same_or_inside,
     runtime_python_activation_hint, runtime_python_env_bin_dir, runtime_python_executable_in_env,
-    shell_command_for_host, uv_cache_source, write_all_tcp_stream,
+    shell_command_for_host, uv_cache_source, uv_python_install_dir_source, write_all_tcp_stream,
 };
 use rocm_engine_protocol::{
     DEFAULT_LOG_TAIL_LINES, DetectRequest, DetectResponse, DevicePolicy,
@@ -481,12 +481,13 @@ rocm logs --search error timeout")]
         /// Keep saved settings.
         #[arg(long)]
         keep_config: bool,
-        /// Keep app data such as logs, services, engines, and the uv package cache
-        /// (often the largest directory rocm-cli manages).
+        /// Keep app data such as logs, services, engines, the uv package cache, and the
+        /// uv-managed Python interpreter (often the largest directories rocm-cli manages).
         #[arg(long)]
         keep_data: bool,
-        /// Keep caches under the cache directory. Does not cover the uv package cache,
-        /// which lives under the data directory; use --keep-data for that.
+        /// Keep caches under the cache directory. Does not cover the uv package cache or
+        /// the uv-managed Python interpreter, which live under the data directory; use
+        /// --keep-data for those.
         #[arg(long)]
         keep_cache: bool,
         /// Allow removing development binaries inside the current build tree.
@@ -1019,6 +1020,7 @@ fn main() -> Result<()> {
 
     maybe_migrate_legacy_dashboard_config();
     maybe_notice_legacy_uv_cache();
+    maybe_notice_legacy_uv_python_install_dir();
 
     let raw_args: Vec<String> = std::env::args().skip(1).collect();
     if raw_args.is_empty() {
@@ -1097,6 +1099,53 @@ fn maybe_notice_legacy_uv_cache() {
     let _ = fs::write(&marker, b"");
 }
 
+/// Legacy `uv`-managed Python install location, used before it was colocated with the
+/// managed data directory. Kept relative so the check works on every platform's home dir.
+const LEGACY_UV_PYTHON_INSTALL_DIR_RELATIVE: [&str; 4] = [".local", "share", "uv", "python"];
+
+/// One-shot notice that pre-colocation `uv`-managed Python interpreters are still
+/// occupying space at the default `uv` location. Nothing is migrated or deleted: removing
+/// it is the user's call. Silent when the managed dir does not exist yet (nothing has
+/// moved) or when an override is in effect.
+fn maybe_notice_legacy_uv_python_install_dir() {
+    let Ok(paths) = AppPaths::discover() else {
+        return;
+    };
+    let install_dir = uv_python_install_dir_source(&paths);
+    if install_dir.is_override() {
+        return;
+    }
+    // Only worth mentioning once the managed dir is actually in use; otherwise the legacy
+    // directory is simply still being used by other tools.
+    if !install_dir.path().is_dir() {
+        return;
+    }
+    let Some(home) = std::env::var_os("HOME")
+        .or_else(|| std::env::var_os("USERPROFILE"))
+        .map(PathBuf::from)
+    else {
+        return;
+    };
+    let legacy = LEGACY_UV_PYTHON_INSTALL_DIR_RELATIVE
+        .iter()
+        .fold(home, |dir, part| dir.join(part));
+    if !legacy.is_dir() {
+        return;
+    }
+    // One-shot: a standing reminder on every invocation would be noise, and the user may
+    // reasonably decide to keep the legacy interpreters for other uv projects.
+    let marker = paths.data_dir.join(".legacy-uv-python-install-dir-notice");
+    if marker.exists() {
+        return;
+    }
+    eprintln!(
+        "rocm: the uv-managed Python interpreter now lives at {}; the previous location at {} is no longer used by rocm-cli and can be removed if no other uv project needs it",
+        install_dir.path().display(),
+        legacy.display()
+    );
+    let _ = fs::write(&marker, b"");
+}
+
 /// One-shot, best-effort migration of a legacy rocm-dash `config.toml` into the
 /// unified `config.json`. Prints a notice when a migration runs;
 /// never fails startup if the legacy file is malformed.
@@ -15769,6 +15818,20 @@ fn shared_cache_candidates() -> Vec<(PathBuf, &'static str)> {
         ));
     }
 
+    // Same reasoning for the standalone interpreters `uv python install` downloads. The
+    // managed location sits under the data directory and is filtered out by
+    // `shared_cache_notes_for`; this only surfaces when it has been pointed elsewhere.
+    let uv_python = env_path("UV_PYTHON_INSTALL_DIR").or_else(|| {
+        rocm_core::runtime_home_dir()
+            .map(|home| home.join(".local").join("share").join("uv").join("python"))
+    });
+    if let Some(path) = uv_python {
+        candidates.push((
+            path,
+            "uv-managed Python interpreters are shared with other uv projects on this computer and are",
+        ));
+    }
+
     let hf_cache = env_path("HF_HOME")
         .map(|home| home.join("hub"))
         .or_else(|| env_path("HUGGINGFACE_HUB_CACHE"))
@@ -17217,6 +17280,31 @@ mod tests {
         let _ = std::fs::remove_dir_all(&root);
     }
 
+    /// The uv-managed Python interpreters are now the other large thing rocm-cli causes
+    /// to be downloaded, so uninstall must account for them the same way it does the uv
+    /// cache. Drives the real candidate list rather than a hand-made one, so deleting the
+    /// production code fails this test.
+    #[test]
+    fn shared_cache_candidates_include_the_uv_python_install_dir() {
+        let lock = super::BUILTIN_ENGINE_ENV_LOCK.get_or_init(|| Mutex::new(()));
+        let _guard = lock.lock().expect("env lock poisoned");
+        let overridden = std::env::temp_dir().join(format!("rocm-uv-py-{}", std::process::id()));
+        let _scoped = super::ScopedEnvVar::set_path("UV_PYTHON_INSTALL_DIR", &overridden);
+
+        let candidates = super::shared_cache_candidates();
+        let entry = candidates
+            .iter()
+            .find(|(path, _)| path == &overridden)
+            .unwrap_or_else(|| {
+                panic!("UV_PYTHON_INSTALL_DIR missing from uninstall candidates: {candidates:?}")
+            });
+        assert!(
+            entry.1.contains("uv-managed Python"),
+            "unexpected description: {}",
+            entry.1
+        );
+    }
+
     /// A cache that does not exist is not worth mentioning.
     #[test]
     fn shared_cache_notes_ignore_missing_paths() {

apps/rocm/src/therock.rs

@@ -15,7 +15,8 @@ use rocm_core::{
 };
 #[cfg(test)]
 use rocm_core::{
-    generate_rsa_signing_keypair, managed_uv_cache_dir, sign_rsa_pkcs1_sha256_signature,
+    generate_rsa_signing_keypair, managed_uv_cache_dir, managed_uv_python_install_dir,
+    sign_rsa_pkcs1_sha256_signature,
 };
 use serde::{Deserialize, Serialize};
 use std::cmp::Ordering;
@@ -3642,6 +3643,23 @@ mod tests {
         assert!(cache.starts_with(&paths.data_dir));
     }
 
+    #[test]
+    fn uv_python_install_dir_does_not_follow_a_prefix_install_root() {
+        // Same documented non-goal as `uv_cache_does_not_follow_a_prefix_install_root`:
+        // `--prefix` moves install_root only, while the interpreters stay keyed off the
+        // data dir. Pins the claim `docs/manual-testing.md` makes about `uv-python`.
+        let (_root, paths) = test_paths("prefix-uv-python");
+        let prefix_root = PathBuf::from("/mnt/elsewhere/envs/my-env");
+        let install_dir = managed_uv_python_install_dir(&paths.data_dir);
+
+        assert!(
+            !install_dir.starts_with(&prefix_root),
+            "python install dir {} unexpectedly followed the --prefix root",
+            install_dir.display()
+        );
+        assert!(install_dir.starts_with(&paths.data_dir));
+    }
+
     #[test]
     fn managed_python_defaults_to_312() {
         assert_eq!(DEFAULT_MANAGED_PYTHON_VERSION, "3.12");

crates/rocm-core/src/lib.rs

@@ -58,23 +58,25 @@ pub use runtime::{
     RuntimeHost, RuntimePlatform, current_executable_path, default_cache_dir, default_config_dir,
     default_data_dir, default_interactive_shell_program, managed_logs_dir, managed_pip_cache_dir,
     managed_runtime_cache_dir, managed_runtime_data_root, managed_tools_dir, managed_uv_cache_dir,
-    normalize_runtime_path_for_host, normalize_runtime_path_for_storage,
-    normalize_runtime_path_text_for_host, normalize_runtime_path_text_for_platform,
-    normalize_runtime_path_text_for_storage, platform_binary_name, prepend_runtime_path,
-    runtime_directory_label, runtime_drive_root_for_key, runtime_drive_roots, runtime_exe_suffix,
-    runtime_home_dir, runtime_install_root_is_protected, runtime_is_linux, runtime_is_windows,
-    runtime_os_name, runtime_path_for_child, runtime_path_for_windows_child,
-    runtime_path_is_same_or_inside, runtime_path_list_join, runtime_path_list_split,
-    runtime_path_sort_key, runtime_path_text_is_absolute_for_host,
-    runtime_path_text_is_absolute_for_platform, runtime_paths_equivalent,
-    runtime_python_activation_hint, runtime_python_activation_script, runtime_python_bin_dir_name,
-    runtime_python_env_bin_dir, runtime_python_executable_in_env, runtime_python_executable_name,
-    runtime_rocm_library_filename, shell_command_for_host,
+    managed_uv_python_install_dir, normalize_runtime_path_for_host,
+    normalize_runtime_path_for_storage, normalize_runtime_path_text_for_host,
+    normalize_runtime_path_text_for_platform, normalize_runtime_path_text_for_storage,
+    platform_binary_name, prepend_runtime_path, runtime_directory_label,
+    runtime_drive_root_for_key, runtime_drive_roots, runtime_exe_suffix, runtime_home_dir,
+    runtime_install_root_is_protected, runtime_is_linux, runtime_is_windows, runtime_os_name,
+    runtime_path_for_child, runtime_path_for_windows_child, runtime_path_is_same_or_inside,
+    runtime_path_list_join, runtime_path_list_split, runtime_path_sort_key,
+    runtime_path_text_is_absolute_for_host, runtime_path_text_is_absolute_for_platform,
+    runtime_paths_equivalent, runtime_python_activation_hint, runtime_python_activation_script,
+    runtime_python_bin_dir_name, runtime_python_env_bin_dir, runtime_python_executable_in_env,
+    runtime_python_executable_name, runtime_rocm_library_filename, shell_command_for_host,
 };
 pub use uv::{
-    DEFAULT_UV_TIMEOUT_SECS, UV_CACHE_DIR_ENV, UV_CACHE_DIR_OVERRIDE_ENV, UvCacheSource,
-    ensure_uv_binary, uv_binary_name, uv_cache_source, uv_command_env, uv_http_timeout_secs,
-    uv_pip_freeze_args, uv_pip_install_base, uv_venv_args,
+    DEFAULT_UV_TIMEOUT_SECS, UV_CACHE_DIR_ENV, UV_CACHE_DIR_OVERRIDE_ENV,
+    UV_PYTHON_INSTALL_DIR_ENV, UV_PYTHON_INSTALL_DIR_OVERRIDE_ENV, UvCacheSource,
+    UvPythonInstallDirSource, ensure_uv_binary, uv_binary_name, uv_cache_source, uv_command_env,
+    uv_http_timeout_secs, uv_pip_freeze_args, uv_pip_install_base, uv_python_install_dir_source,
+    uv_venv_args,
 };
 
 pub const DEFAULT_LOCAL_PORT: u16 = 11_435;

crates/rocm-core/src/runtime.rs

@@ -232,6 +232,15 @@ pub fn managed_uv_cache_dir(root: &Path) -> PathBuf {
     normalize_runtime_path_for_host(root).join("uv-cache")
 }
 
+/// Standalone CPython interpreters downloaded by `uv python install`, kept under the managed
+/// root for the same reason as `managed_uv_cache_dir`.
+///
+/// Without this, `uv` falls back to `$HOME/.local/share/uv/python/`, leaking outside the
+/// managed root.
+pub fn managed_uv_python_install_dir(root: &Path) -> PathBuf {
+    normalize_runtime_path_for_host(root).join("uv-python")
+}
+
 pub fn managed_logs_dir(root: &Path) -> PathBuf {
     normalize_runtime_path_for_host(root).join("logs")
 }