Add `--show-urls` and `--only-downloads` to `uv python list` (#8062)

These are useful for creating a mirror of the Python downloads for a
given uv version, e.g.:

```
❯ cargo run -q -- python list --show-urls --only-downloads
cpython-3.13.0-macos-aarch64-none     https://github.com/indygreg/python-build-standalone/releases/download/20241008/cpython-3.13.0%2B20241008-aarch64-apple-darwin-install_only_stripped.tar.gz
cpython-3.12.7-macos-aarch64-none     https://github.com/indygreg/python-build-standalone/releases/download/20241008/cpython-3.12.7%2B20241008-aarch64-apple-darwin-install_only_stripped.tar.gz
cpython-3.11.10-macos-aarch64-none    https://github.com/indygreg/python-build-standalone/releases/download/20241008/cpython-3.11.10%2B20241008-aarch64-apple-darwin-install_only_stripped.tar.gz
cpython-3.10.15-macos-aarch64-none    https://github.com/indygreg/python-build-standalone/releases/download/20241008/cpython-3.10.15%2B20241008-aarch64-apple-darwin-install_only_stripped.tar.gz
cpython-3.9.20-macos-aarch64-none     https://github.com/indygreg/python-build-standalone/releases/download/20241008/cpython-3.9.20%2B20241008-aarch64-apple-darwin-install_only_stripped.tar.gz
cpython-3.8.20-macos-aarch64-none     https://github.com/indygreg/python-build-standalone/releases/download/20241002/cpython-3.8.20%2B20241002-aarch64-apple-darwin-install_only_stripped.tar.gz
pypy-3.10.14-macos-aarch64-none       https://downloads.python.org/pypy/pypy3.10-v7.3.17-macos_arm64.tar.bz2
pypy-3.9.19-macos-aarch64-none        https://downloads.python.org/pypy/pypy3.9-v7.3.16-macos_arm64.tar.bz2
pypy-3.8.16-macos-aarch64-none        https://downloads.python.org/pypy/pypy3.8-v7.3.11-macos_arm64.tar.bz2
```

crates/uv-cli/src/lib.rs

@@ -4225,8 +4225,20 @@ pub struct PythonListArgs {
     /// Only show installed Python versions, exclude available downloads.
     ///
     /// By default, available downloads for the current platform are shown.
-    #[arg(long)]
+    #[arg(long, conflicts_with("only_downloads"))]
     pub only_installed: bool,
+
+    /// Only show Python downloads, exclude installed distributions.
+    ///
+    /// By default, available downloads for the current platform are shown.
+    #[arg(long, conflicts_with("only_installed"))]
+    pub only_downloads: bool,
+
+    /// Show the URLs of available Python downloads.
+    ///
+    /// By default, these display as `<download available>`.
+    #[arg(long)]
+    pub show_urls: bool,
 }
 
 #[derive(Args)]

crates/uv/src/commands/python/list.rs

@@ -2,6 +2,7 @@ use std::collections::BTreeSet;
 use std::fmt::Write;
 
 use anyhow::Result;
+use itertools::Either;
 use owo_colors::OwoColorize;
 use rustc_hash::FxHashSet;
 use uv_cache::Cache;
@@ -29,6 +30,7 @@ pub(crate) async fn list(
     kinds: PythonListKinds,
     all_versions: bool,
     all_platforms: bool,
+    show_urls: bool,
     python_preference: PythonPreference,
     python_downloads: PythonDownloads,
     cache: &Cache,
@@ -38,6 +40,11 @@ pub(crate) async fn list(
     if python_preference != PythonPreference::OnlySystem {
         let download_request = match kinds {
             PythonListKinds::Installed => None,
+            PythonListKinds::Downloads => Some(if all_platforms {
+                PythonDownloadRequest::default()
+            } else {
+                PythonDownloadRequest::from_env()?
+            }),
             PythonListKinds::Default => {
                 if python_downloads.is_automatic() {
                     Some(if all_platforms {
@@ -61,11 +68,18 @@ pub(crate) async fn list(
             .flatten();
 
         for download in downloads {
-            output.insert((download.key().clone(), Kind::Download, None));
+            output.insert((
+                download.key().clone(),
+                Kind::Download,
+                Either::Right(download.url()),
+            ));
         }
     };
 
-    let installed = find_python_installations(
+    let installed =
+        match kinds {
+            PythonListKinds::Installed | PythonListKinds::Default => {
+                Some(find_python_installations(
                 &PythonRequest::Any,
                 EnvironmentPreference::OnlySystem,
                 python_preference,
@@ -81,8 +95,12 @@ pub(crate) async fn list(
             .collect::<Result<Vec<Result<PythonInstallation, PythonNotFound>>, DiscoveryError>>()?
             .into_iter()
             // Drop any "missing" installations
-    .filter_map(Result::ok);
+            .filter_map(Result::ok))
+            }
+            PythonListKinds::Downloads => None,
+        };
 
+    if let Some(installed) = installed {
         for installation in installed {
             let kind = if matches!(installation.source(), PythonSource::Managed) {
                 Kind::Managed
@@ -92,17 +110,18 @@ pub(crate) async fn list(
             output.insert((
                 installation.key(),
                 kind,
-            Some(installation.interpreter().sys_executable().to_path_buf()),
+                Either::Left(installation.interpreter().sys_executable().to_path_buf()),
             ));
         }
+    }
 
     let mut seen_minor = FxHashSet::default();
     let mut seen_patch = FxHashSet::default();
     let mut seen_paths = FxHashSet::default();
     let mut include = Vec::new();
-    for (key, kind, path) in output.iter().rev() {
+    for (key, kind, uri) in output.iter().rev() {
         // Do not show the same path more than once
-        if let Some(path) = path {
+        if let Either::Left(path) = uri {
             if !seen_paths.insert(path) {
                 continue;
             }
@@ -142,7 +161,7 @@ pub(crate) async fn list(
                 }
             }
         }
-        include.push((key, path));
+        include.push((key, uri));
     }
 
     // Compute the width of the first column.
@@ -150,9 +169,10 @@ pub(crate) async fn list(
         .iter()
         .fold(0usize, |acc, (key, _)| acc.max(key.to_string().len()));
 
-    for (key, path) in include {
+    for (key, uri) in include {
         let key = key.to_string();
-        if let Some(path) = path {
+        match uri {
+            Either::Left(path) => {
                 let is_symlink = fs_err::symlink_metadata(path)?.is_symlink();
                 if is_symlink {
                     writeln!(
@@ -168,6 +188,10 @@ pub(crate) async fn list(
                         path.user_display().cyan()
                     )?;
                 }
+            }
+            Either::Right(url) => {
+                if show_urls {
+                    writeln!(printer.stdout(), "{key:width$}    {}", url.dimmed())?;
                 } else {
                     writeln!(
                         printer.stdout(),
@@ -176,6 +200,8 @@ pub(crate) async fn list(
                     )?;
                 }
             }
+        }
+    }
 
     Ok(ExitStatus::Success)
 }

crates/uv/src/lib.rs

@@ -1088,6 +1088,7 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
                 args.kinds,
                 args.all_versions,
                 args.all_platforms,
+                args.show_urls,
                 globals.python_preference,
                 globals.python_downloads,
                 &cache,

crates/uv/src/settings.rs

@@ -703,6 +703,9 @@ impl ToolDirSettings {
 pub(crate) enum PythonListKinds {
     #[default]
     Default,
+    /// Only list version downloads.
+    Downloads,
+    /// Only list installed versions.
     Installed,
 }
 
@@ -713,6 +716,7 @@ pub(crate) struct PythonListSettings {
     pub(crate) kinds: PythonListKinds,
     pub(crate) all_platforms: bool,
     pub(crate) all_versions: bool,
+    pub(crate) show_urls: bool,
 }
 
 impl PythonListSettings {
@@ -723,10 +727,14 @@ impl PythonListSettings {
             all_versions,
             all_platforms,
             only_installed,
+            only_downloads,
+            show_urls,
         } = args;
 
         let kinds = if only_installed {
             PythonListKinds::Installed
+        } else if only_downloads {
+            PythonListKinds::Downloads
         } else {
             PythonListKinds::default()
         };
@@ -735,6 +743,7 @@ impl PythonListSettings {
             kinds,
             all_platforms,
             all_versions,
+            show_urls,
         }
     }
 }

docs/reference/cli.md

@@ -4426,6 +4426,10 @@ uv python list [OPTIONS]
 
 <p>When disabled, uv will only use locally cached data and locally available files.</p>
 
+</dd><dt><code>--only-downloads</code></dt><dd><p>Only show Python downloads, exclude installed distributions.</p>
+
+<p>By default, available downloads for the current platform are shown.</p>
+
 </dd><dt><code>--only-installed</code></dt><dd><p>Only show installed Python versions, exclude available downloads.</p>
 
 <p>By default, available downloads for the current platform are shown.</p>
@@ -4458,6 +4462,10 @@ uv python list [OPTIONS]
 </ul>
 </dd><dt><code>--quiet</code>, <code>-q</code></dt><dd><p>Do not print any output</p>
 
+</dd><dt><code>--show-urls</code></dt><dd><p>Show the URLs of available Python downloads.</p>
+
+<p>By default, these display as <code>&lt;download available&gt;</code>.</p>
+
 </dd><dt><code>--verbose</code>, <code>-v</code></dt><dd><p>Use verbose output.</p>
 
 <p>You can configure fine-grained logging using the <code>RUST_LOG</code> environment variable. (&lt;https://docs.rs/tracing-subscriber/latest/tracing_subscriber/filter/struct.EnvFilter.html#directives&gt;)</p>