ostree-ext: Replace config loading with a stub if we detect mock

Workaround for rpm-software-management/mock#1613 (comment)

Signed-off-by: Colin Walters <[email protected]>

Author: cgwalters

crates/ostree-ext/src/globals.rs

@@ -81,8 +81,22 @@ impl ConfigPaths {
 
 /// Return the path to the global container authentication file, if it exists.
 pub fn get_global_authfile(root: &Dir) -> Result<Option<(Utf8PathBuf, File)>> {
-    let root = &RootDir::new(root, ".")?;
+    // Workaround for https://github.com/rpm-software-management/mock/pull/1613#issuecomment-3421908652
+    #[cfg(test)]
+    {
+        if matches!(
+            (
+                std::env::var("HOSTNAME").ok().as_deref(),
+                std::env::var("container").ok().as_deref()
+            ),
+            (Some("mock"), Some("systemd-nspawn"))
+        ) {
+            return Ok(None);
+        }
+    }
+
     let am_uid0 = rustix::process::getuid() == rustix::process::Uid::ROOT;
+    let root = &RootDir::new(root, ".")?;
     get_global_authfile_impl(root, am_uid0)
 }