tests: cache managed Python installs

crates/uv/tests/it/common/mod.rs

@@ -486,17 +486,24 @@ impl TestContext {
 
     /// Use a shared global cache for Python downloads.
     #[must_use]
-    pub fn with_python_download_cache(mut self) -> Self {
-        self.extra_env.push((
-            EnvVars::UV_PYTHON_CACHE_DIR.into(),
-            // Respect `UV_PYTHON_CACHE_DIR` if set, or use the default cache directory
-            env::var_os(EnvVars::UV_PYTHON_CACHE_DIR).unwrap_or_else(|| {
-                uv_cache::Cache::from_settings(false, None)
-                    .unwrap()
-                    .bucket(CacheBucket::Python)
-                    .into()
-            }),
-        ));
+    fn with_python_download_cache(mut self) -> Self {
+        let key: OsString = EnvVars::UV_PYTHON_CACHE_DIR.into();
+        self.extra_env.retain(|(existing, _)| existing != &key);
+        let value = env::var_os(EnvVars::UV_PYTHON_CACHE_DIR).unwrap_or_else(|| {
+            uv_cache::Cache::from_settings(false, None)
+                .unwrap()
+                .bucket(CacheBucket::Python)
+                .into()
+        });
+        self.extra_env.push((key, value));
+        self
+    }
+
+    /// Disable the shared global cache for Python downloads.
+    #[must_use]
+    pub fn without_python_download_cache(mut self) -> Self {
+        let key: OsString = EnvVars::UV_PYTHON_CACHE_DIR.into();
+        self.extra_env.retain(|(existing, _)| existing != &key);
         self
     }
 
@@ -514,6 +521,8 @@ impl TestContext {
     pub fn with_managed_python_dirs(mut self) -> Self {
         let managed = self.temp_dir.join("managed");
 
+        self = self.with_python_download_cache();
+
         self.extra_env.push((
             EnvVars::UV_PYTHON_BIN_DIR.into(),
             self.bin_dir.as_os_str().to_owned(),

crates/uv/tests/it/pip_install.rs

@@ -13121,7 +13121,6 @@ fn pip_install_no_sources_editable_to_registry_switch() -> Result<()> {
 #[test]
 fn install_with_system_interpreter() {
     let context = TestContext::new_with_versions(&[])
-        .with_python_download_cache()
         .with_managed_python_dirs()
         .with_filtered_python_keys();
 
@@ -13151,9 +13150,7 @@ fn install_with_system_interpreter() {
 #[test]
 fn install_missing_python_no_target() {
     // Create a context that only has Python 3.11 available.
-    let context = TestContext::new("3.11")
-        .with_python_download_cache()
-        .with_managed_python_dirs();
+    let context = TestContext::new("3.11").with_managed_python_dirs();
 
     // Request Python 3.12; which should fail
     uv_snapshot!(context.filters(), context.pip_install()
@@ -13174,9 +13171,7 @@ fn install_missing_python_no_target() {
 #[test]
 fn install_missing_python_with_target() {
     // Create a context with no installed python interpreters.
-    let context = TestContext::new_with_versions(&[])
-        .with_python_download_cache()
-        .with_managed_python_dirs();
+    let context = TestContext::new_with_versions(&[]).with_managed_python_dirs();
 
     let target_dir = context.temp_dir.child("target-dir");
 
@@ -13203,9 +13198,7 @@ fn install_missing_python_with_target() {
 #[test]
 fn install_missing_python_version_with_target() {
     // Create a context that only has Python 3.11 available.
-    let context = TestContext::new("3.11")
-        .with_python_download_cache()
-        .with_managed_python_dirs();
+    let context = TestContext::new("3.11").with_managed_python_dirs();
 
     let target_dir = context.temp_dir.child("target-dir");
 

crates/uv/tests/it/pip_sync.rs

@@ -6167,9 +6167,7 @@ fn incompatible_platform_direct_url() -> Result<()> {
 #[test]
 fn sync_missing_python_no_target() -> Result<()> {
     // Create a context that only has Python 3.11 available.
-    let context = TestContext::new("3.11")
-        .with_python_download_cache()
-        .with_managed_python_dirs();
+    let context = TestContext::new("3.11").with_managed_python_dirs();
 
     let requirements = context.temp_dir.child("requirements.txt");
     requirements.write_str("anyio")?;
@@ -6193,9 +6191,7 @@ fn sync_missing_python_no_target() -> Result<()> {
 #[test]
 fn sync_with_target_installs_missing_python() -> Result<()> {
     // Create a context that only has Python 3.11 available.
-    let context = TestContext::new("3.11")
-        .with_python_download_cache()
-        .with_managed_python_dirs();
+    let context = TestContext::new("3.11").with_managed_python_dirs();
 
     let target_dir = context.temp_dir.child("target-dir");
     let requirements = context.temp_dir.child("requirements.txt");

crates/uv/tests/it/python_find.rs

@@ -1264,7 +1264,6 @@ fn python_find_freethreaded_313() {
         .with_filtered_python_keys()
         .with_filtered_python_sources()
         .with_managed_python_dirs()
-        .with_python_download_cache()
         .with_filtered_python_install_bin()
         .with_filtered_python_names()
         .with_filtered_exe_suffix();
@@ -1303,7 +1302,6 @@ fn python_find_freethreaded_314() {
         .with_filtered_python_keys()
         .with_filtered_python_sources()
         .with_managed_python_dirs()
-        .with_python_download_cache()
         .with_filtered_python_install_bin()
         .with_filtered_python_names()
         .with_filtered_exe_suffix();
@@ -1380,7 +1378,6 @@ fn python_find_prerelease_version_specifiers() {
         .with_filtered_python_keys()
         .with_filtered_python_sources()
         .with_managed_python_dirs()
-        .with_python_download_cache()
         .with_filtered_python_install_bin()
         .with_filtered_python_names()
         .with_filtered_exe_suffix();
@@ -1479,7 +1476,6 @@ fn python_find_prerelease_with_patch_request() {
         .with_filtered_python_keys()
         .with_filtered_python_sources()
         .with_managed_python_dirs()
-        .with_python_download_cache()
         .with_filtered_python_install_bin()
         .with_filtered_python_names()
         .with_filtered_exe_suffix();