port all old tests to the new fixture (#16)

Author: Byron

tests/index/mod.rs

@@ -4,25 +4,26 @@ use std::path::PathBuf;
 
 mod changes_from_objects;
 
+const NUM_CHANGES_SINCE_EVER: usize = 3516;
+
 #[test]
-fn peek_changes() {
-    let mut index = index_ro().unwrap();
+fn peek_changes() -> crate::Result {
+    let mut index = index_ro()?;
     index.branch_name = "main";
     assert!(
         index.last_seen_reference().is_err(),
         "marker ref doesn't exist"
     );
-    let (changes, last_seen_revision) = index.peek_changes().unwrap();
+    let (changes, last_seen_revision) = index.peek_changes()?;
     assert_eq!(
         changes.len(),
-        3516,
+        NUM_CHANGES_SINCE_EVER,
         "all changes since the beginning of history"
     );
 
     let origin_main = index
         .repository()
-        .find_reference("refs/remotes/origin/main")
-        .unwrap();
+        .find_reference("refs/remotes/origin/main")?;
     assert_eq!(
         last_seen_revision,
         origin_main.target().expect("direct ref"),
@@ -32,26 +33,81 @@ fn peek_changes() {
         index.last_seen_reference().is_err(),
         "the last-seen reference has not been created"
     );
+    Ok(())
 }
 
 #[test]
 fn clone_if_needed() {
     let tmp = TempDir::new().unwrap();
-    let options = || crates_index_diff::index::CloneOptions {
-        repository_url: fixture_dir().unwrap().join("base").display().to_string(),
-        fetch_options: None,
-    };
-    Index::from_path_or_cloned_with_options(tmp.path(), options())
+    Index::from_path_or_cloned_with_options(tmp.path(), clone_options())
         .expect("successful clone to be created");
-    Index::from_path_or_cloned_with_options(tmp.path(), options())
+    Index::from_path_or_cloned_with_options(tmp.path(), clone_options())
         .expect("second instance re-uses existing clone");
 }
 
+#[test]
+fn quick_changes_since_last_fetch() {
+    let (index, _tmp) = index_rw().unwrap();
+    assert!(index.last_seen_reference().is_err(), "no marker exists");
+    let num_changes_since_first_commit = index.fetch_changes().unwrap().len();
+    assert_eq!(
+        num_changes_since_first_commit, NUM_CHANGES_SINCE_EVER,
+        "all changes since ever"
+    );
+    let mut marker = index
+        .last_seen_reference()
+        .expect("must be created/update now");
+    let remote_main = index
+        .repository()
+        .find_reference("refs/remotes/origin/main")
+        .unwrap();
+    assert_eq!(
+        marker.target(),
+        remote_main.target(),
+        "we are updated to the most recent known version of the remote"
+    );
+
+    // reset to previous one
+    marker
+        .set_target(
+            index
+                .repository()
+                .revparse_single(&format!("{}~2", index.seen_ref_name))
+                .unwrap()
+                .id(),
+            "resetting to previous commit",
+        )
+        .expect("reset success");
+    let num_seen_after_reset = index.fetch_changes().unwrap().len();
+    assert_eq!(
+        marker.target(),
+        remote_main.target(),
+        "seen branch was updated again"
+    );
+    assert_eq!(
+        num_seen_after_reset, 2357,
+        "normalization has no changes, but the commit before has one"
+    );
+
+    assert_eq!(
+        index.fetch_changes().unwrap().len(),
+        0,
+        "nothing if there was no change"
+    );
+}
+
 fn index_ro() -> crate::Result<Index> {
     let dir = fixture_dir()?;
     Ok(Index::from_path_or_cloned(dir.join("clone"))?)
 }
 
+fn index_rw() -> crate::Result<(Index, TempDir)> {
+    let tmp = TempDir::new().unwrap();
+    let mut index = Index::from_path_or_cloned_with_options(tmp.path(), clone_options())?;
+    index.branch_name = "main";
+    Ok((index, tmp))
+}
+
 fn fixture_dir() -> crate::Result<PathBuf> {
     Ok(git_testtools::scripted_fixture_repo_read_only_with_args(
         "make-index-from-parts.sh",
@@ -61,4 +117,9 @@ fn fixture_dir() -> crate::Result<PathBuf> {
     )?)
 }
 
-mod old;
+fn clone_options() -> crates_index_diff::index::CloneOptions<'static> {
+    crates_index_diff::index::CloneOptions {
+        repository_url: fixture_dir().unwrap().join("base").display().to_string(),
+        fetch_options: None,
+    }
+}