Don't consume unblamed hunk following deletion

There might be more changes that are supposed to affect the unblamed
hunk. The deletion might, for example, be followed by another deletion
or by an addition both of which would have an effect on the offset that
needs to be applied to the unblamed hunk.

Author: cruessler

gix-blame/tests/blame.rs

@@ -570,15 +570,7 @@ fn process_change(
 
                 *offset_in_destination -= number_of_lines_deleted;
 
-                let line_range_in_next_destination =
-                    LineRange::with_offset(hunk.range_in_destination.clone(), *offset_in_destination);
-
-                new_hunks_to_blame.push(UnblamedHunk::from_destination(
-                    line_range_in_next_destination.into(),
-                    hunk.offset() + *offset_in_destination,
-                ));
-
-                (None, None)
+                (Some(hunk), None)
             } else if line_number_in_destination < hunk.range_in_destination.end {
                 //  <----->  (hunk)
                 //     |     (line_number_in_destination)
@@ -1582,6 +1574,36 @@ fn process_change_works_no_overlap_5() {
     assert_eq!(offset_in_destination, Offset::Added(1));
 }
 
+#[test]
+fn process_change_works_no_overlap_6() {
+    let mut lines_blamed: Vec<BlameEntry> = vec![];
+    let mut new_hunks_to_blame: Vec<UnblamedHunk> = vec![];
+    let mut offset_in_destination: Offset = Offset::Added(0);
+    let suspect = ObjectId::null(gix_hash::Kind::Sha1);
+
+    let (hunk, change) = process_change(
+        &mut lines_blamed,
+        &mut new_hunks_to_blame,
+        &mut offset_in_destination,
+        suspect,
+        // range_in_destination: 22..24
+        Some(UnblamedHunk::new(23..25, Offset::Added(1))),
+        Some(Change::Deleted(20, 1)),
+    );
+
+    assert_eq!(
+        hunk,
+        Some(UnblamedHunk {
+            range_in_blamed_file: 23..25,
+            range_in_destination: 22..24
+        })
+    );
+    assert_eq!(change, None);
+    assert_eq!(lines_blamed, vec![]);
+    assert_eq!(new_hunks_to_blame, vec![]);
+    assert_eq!(offset_in_destination, Offset::Deleted(1));
+}
+
 #[test]
 fn process_change_works_unchanged_hunk() {
     let mut lines_blamed: Vec<BlameEntry> = vec![];
@@ -1729,10 +1751,16 @@ fn process_change_works_deleted_hunk_2() {
         Some(Change::Deleted(0, 4)),
     );
 
-    assert_eq!(hunk, None);
+    assert_eq!(
+        hunk,
+        Some(UnblamedHunk {
+            range_in_blamed_file: 2..16,
+            range_in_destination: 2..16
+        })
+    );
     assert_eq!(change, None);
     assert_eq!(lines_blamed, vec![]);
-    assert_eq!(new_hunks_to_blame, vec![UnblamedHunk::new(2..16, Offset::Deleted(4))]);
+    assert_eq!(new_hunks_to_blame, vec![]);
     assert_eq!(offset_in_destination, Offset::Deleted(4));
 }