Refuse to remove the target directory if it is not a python installat…

…ion (#921)

CHANGELOG.md

@@ -11,10 +11,11 @@ _Unreleased_
 
 - Always create `.gitignore` file in `rye init`.  #919
 
+- Prevent `rye fetch --force` from removing a target directory that is not a Python installation.  #921
+
 - `rye list` always prints the currently installed packages even this project is not managed by Rye.  #940
 
 - Fix error on using -v or -q with `rye fmt` or `rye lint`. #959
-- Fix error on using -v or -q with `rye fmt` or `rye lint`.  #959
 
 - Fix rye fetch detection of registered toolchain.  #931
 

rye/src/bootstrap.rs

@@ -14,7 +14,8 @@ use tempfile::tempdir_in;
 use crate::config::Config;
 use crate::piptools::LATEST_PIP;
 use crate::platform::{
-    get_app_dir, get_canonical_py_path, get_toolchain_python_bin, list_known_toolchains,
+    get_app_dir, get_canonical_py_path, get_python_bin_within, get_toolchain_python_bin,
+    list_known_toolchains,
 };
 use crate::pyproject::latest_available_python_version;
 use crate::sources::py::{get_download_url, PythonVersion, PythonVersionRequest};
@@ -396,11 +397,23 @@ pub fn fetch(
 
     let target_dir = match options.target_path {
         Some(ref target_dir) => {
-            echo!(if options.output, "downloading to: {}", target_dir.display());
+            if target_dir.is_file() {
+                bail!("target directory '{}' is a file", target_dir.display());
+            }
+            echo!(if options.output, "Downloading to '{}'", target_dir.display());
             if target_dir.is_dir() {
                 if options.force {
+                    // Refuse to remove the target directory if it's not empty and not a python installation
+                    if target_dir.read_dir()?.next().is_some()
+                        && !get_python_bin_within(target_dir).exists()
+                    {
+                        bail!(
+                            "target directory '{}' exists and is not a Python installation",
+                            target_dir.display()
+                        );
+                    }
                     fs::remove_dir_all(target_dir)
-                        .path_context(target_dir, "could not remove target director")?;
+                        .path_context(target_dir, "could not remove target directory")?;
                 } else {
                     bail!("target directory '{}' exists", target_dir.display());
                 }
@@ -449,7 +462,7 @@ pub fn fetch(
     let with_build_info = options
         .build_info
         .unwrap_or_else(|| Config::current().fetch_with_build_info());
-    let temp_dir = tempdir_in(target_dir.parent().unwrap()).context("temporary unpack location")?;
+    let temp_dir = tempdir_in(parent).context("temporary unpack location")?;
 
     unpack_archive(&archive_buffer, temp_dir.path(), 1).with_context(|| {
         format!(

rye/src/platform.rs

@@ -62,7 +62,7 @@ pub fn get_canonical_py_path(version: &PythonVersion) -> Result<PathBuf, Error>
 
 /// Returns the path of the python binary for the given version.
 pub fn get_toolchain_python_bin(version: &PythonVersion) -> Result<PathBuf, Error> {
-    let mut p = get_canonical_py_path(version)?;
+    let p = get_canonical_py_path(version)?;
 
     // It's permissible to link Python binaries directly in two ways.  It can either be
     // a symlink in which case it's used directly, it can be a non-executable text file
@@ -83,26 +83,31 @@ pub fn get_toolchain_python_bin(version: &PythonVersion) -> Result<PathBuf, Erro
         return Ok(PathBuf::from(contents.trim_end()));
     }
 
+    Ok(get_python_bin_within(&p))
+}
+
+/// Returns the path to the python binary within the path.
+pub fn get_python_bin_within(path: &Path) -> PathBuf {
+    let mut path = path.to_path_buf();
     // we support install/bin/python, install/python and bin/python
-    p.push("install");
-    if !p.is_dir() {
-        p.pop();
+    path.push("install");
+    if !path.is_dir() {
+        path.pop();
     }
-    p.push("bin");
-    if !p.is_dir() {
-        p.pop();
+    path.push("bin");
+    if !path.is_dir() {
+        path.pop();
     }
 
     #[cfg(unix)]
     {
-        p.push("python3");
+        path.push("python3");
     }
     #[cfg(windows)]
     {
-        p.push("python.exe");
+        path.push("python.exe");
     }
-
-    Ok(p)
+    path
 }
 
 /// Returns a pinnable version for this version request.