Enable `uv tool uninstall uv` on Windows (#8963)

## Summary

Extending self-delete and self-replace functionality to uv itself on
Windows.

Closes https://github.com/astral-sh/uv/issues/6400.

Cargo.lock

@@ -4432,6 +4432,7 @@ dependencies = [
  "reqwest",
  "rkyv",
  "rustc-hash",
+ "self-replace",
  "serde",
  "serde_json",
  "similar",

crates/uv-tool/src/lib.rs

@@ -184,6 +184,8 @@ impl InstalledTools {
             environment_path.user_display()
         );
 
+        // TODO(charlie): On Windows, if the current executable is in the directory,
+        // we need to use `safe_delete`.
         fs_err::remove_dir_all(environment_path)?;
 
         Ok(())

crates/uv-virtualenv/src/virtualenv.rs

@@ -86,6 +86,8 @@ pub(crate) fn create(
                 if allow_existing {
                     debug!("Allowing existing directory");
                 } else if location.join("pyvenv.cfg").is_file() {
+                    // TODO(charlie): On Windows, if the current executable is in the directory,
+                    // we need to use `safe_delete`.
                     debug!("Removing existing directory");
                     fs::remove_dir_all(location)?;
                     fs::create_dir_all(location)?;

crates/uv/Cargo.toml

@@ -99,6 +99,9 @@ walkdir = { workspace = true }
 which = { workspace = true }
 zip = { workspace = true }
 
+[target.'cfg(target_os = "windows")'.dependencies]
+self-replace = { workspace = true }
+
 [dev-dependencies]
 assert_cmd = { version = "2.0.16" }
 assert_fs = { version = "1.1.2" }

crates/uv/src/commands/tool/common.rs

@@ -125,20 +125,13 @@ pub(crate) fn install_executables(
         return Ok(ExitStatus::Failure);
     }
 
-    // Check if they exist, before installing
+    // Error if we're overwriting an existing entrypoint, unless the user passed `--force`.
+    if !force {
         let mut existing_entry_points = target_entry_points
             .iter()
             .filter(|(_, _, target_path)| target_path.exists())
             .peekable();
-
-    // Ignore any existing entrypoints if the user passed `--force`, or the existing recept was
-    // broken.
-    if force {
-        for (name, _, target) in existing_entry_points {
-            debug!("Removing existing executable: `{name}`");
-            fs_err::remove_file(target)?;
-        }
-    } else if existing_entry_points.peek().is_some() {
+        if existing_entry_points.peek().is_some() {
             // Clean up the environment we just created
             installed_tools.remove_environment(name)?;
 
@@ -159,14 +152,26 @@ pub(crate) fn install_executables(
                     .join(", ")
             )
         }
+    }
+
+    #[cfg(windows)]
+    let itself = std::env::current_exe().ok();
 
     for (name, source_path, target_path) in &target_entry_points {
         debug!("Installing executable: `{name}`");
+
         #[cfg(unix)]
         replace_symlink(source_path, target_path).context("Failed to install executable")?;
+
         #[cfg(windows)]
+        if itself.as_ref().is_some_and(|itself| {
+            std::path::absolute(target_path).is_ok_and(|target| *itself == target)
+        }) {
+            self_replace::self_replace(source_path).context("Failed to install entrypoint")?;
+        } else {
             fs_err::copy(source_path, target_path).context("Failed to install entrypoint")?;
         }
+    }
 
     let s = if target_entry_points.len() == 1 {
         ""

crates/uv/src/commands/tool/uninstall.rs

@@ -180,6 +180,9 @@ async fn uninstall_tool(
     // Remove the tool itself.
     tools.remove_environment(name)?;
 
+    #[cfg(windows)]
+    let itself = std::env::current_exe().ok();
+
     // Remove the tool's entrypoints.
     let entrypoints = receipt.entrypoints();
     for entrypoint in entrypoints {
@@ -187,6 +190,15 @@ async fn uninstall_tool(
             "Removing executable: {}",
             entrypoint.install_path.user_display()
         );
+
+        #[cfg(windows)]
+        if itself.as_ref().is_some_and(|itself| {
+            std::path::absolute(&entrypoint.install_path).is_ok_and(|target| *itself == target)
+        }) {
+            self_replace::self_delete()?;
+            continue;
+        }
+
         match fs_err::tokio::remove_file(&entrypoint.install_path).await {
             Ok(()) => {}
             Err(err) if err.kind() == std::io::ErrorKind::NotFound => {