Add tests for checking out in non-empty folder

Author: j-walther

gix/tests/gix/clone.rs

@@ -550,6 +550,33 @@ mod blocking_io {
         assure_index_entries_on_disk(&index, repo.workdir().expect("non-bare"));
         Ok(())
     }
+
+    #[test]
+    fn fetch_and_checkout_into_non_empty_directory_is_allowed_by_default() -> crate::Result {
+        let tmp = gix_testtools::tempfile::TempDir::new()?;
+        let existing_path = tmp.path().join("existing.txt");
+        let existing_content = b"I was here before you";
+        std::fs::write(&existing_path, existing_content)?;
+
+        let mut prepare = gix::clone::PrepareFetch::new(
+            remote::repo("base").path(),
+            tmp.path(),
+            gix::create::Kind::WithWorktree,
+            Default::default(),
+            restricted(),
+        )?;
+        let (mut checkout, _out) =
+            prepare.fetch_then_checkout(gix::progress::Discard, &std::sync::atomic::AtomicBool::default())?;
+        let (repo, _) = checkout.main_worktree(gix::progress::Discard, &std::sync::atomic::AtomicBool::default())?;
+
+        let index = repo.index()?;
+        assert_eq!(index.entries().len(), 1, "All entries are known as per HEAD tree");
+        assure_index_entries_on_disk(&index, repo.workdir().expect("non-bare"));
+
+        assert_eq!(std::fs::read(&existing_path)?, existing_content);
+        Ok(())
+    }
+
     #[test]
     fn fetch_and_checkout_specific_ref() -> crate::Result {
         let tmp = gix_testtools::tempfile::TempDir::new()?;
@@ -800,6 +827,28 @@ fn clone_and_destination_must_be_empty() -> crate::Result {
     Ok(())
 }
 
+#[test]
+fn clone_with_worktree_and_destination_must_be_empty() -> crate::Result {
+    let tmp = gix_testtools::tempfile::TempDir::new()?;
+    std::fs::write(tmp.path().join("file"), b"hello")?;
+    match gix::clone::PrepareFetch::new(
+        remote::repo("base").path(),
+        tmp.path(),
+        gix::create::Kind::WithWorktree,
+        gix::create::Options {
+            destination_must_be_empty: true,
+            ..Default::default()
+        },
+        restricted(),
+    ) {
+        Ok(_) => unreachable!("this should fail as the directory isn't empty"),
+        Err(err) => assert!(err
+            .to_string()
+            .starts_with("Refusing to initialize the non-empty directory as ")),
+    }
+    Ok(())
+}
+
 #[test]
 fn clone_bare_into_empty_directory_and_early_drop() -> crate::Result {
     let tmp = gix_testtools::tempfile::TempDir::new()?;