Don't consume addition preceding unblamed hunk

The addition might match subsequent unblamed hunks.

Author: cruessler

gix-blame/tests/blame.rs

@@ -534,21 +534,25 @@ 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,
-                    ));
-
                     let new_change = if added.end <= hunk.range_in_destination.start {
                         None
                     } else {
                         Some(Change::Added(added.clone(), number_of_lines_deleted))
                     };
 
-                    (None, new_change)
+                    if added.end <= hunk.range_in_destination.start {
+                        (Some(hunk.clone()), new_change)
+                    } else {
+                        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, new_change)
+                    }
                 }
             }
         }
@@ -1439,19 +1443,49 @@ fn process_change_works_no_overlap_2() {
         Some(Change::Added(2..5, 0)),
     );
 
-    assert_eq!(hunk, None);
-    assert_eq!(change, None);
-    assert_eq!(lines_blamed, vec![]);
     assert_eq!(
-        new_hunks_to_blame,
-        vec![UnblamedHunk {
+        hunk,
+        Some(UnblamedHunk {
             range_in_blamed_file: 9..11,
-            range_in_destination: 3..5
-        }]
+            range_in_destination: 6..8
+        })
     );
+    assert_eq!(change, None);
+    assert_eq!(lines_blamed, vec![]);
+    assert_eq!(new_hunks_to_blame, vec![]);
     assert_eq!(offset_in_destination, Offset::Added(3));
 }
 
+#[test]
+fn process_change_works_no_overlap_3() {
+    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: 5..15
+        Some(UnblamedHunk::new(4..15, Offset::Deleted(1))),
+        Some(Change::Added(4..5, 1)),
+    );
+
+    assert_eq!(
+        hunk,
+        Some(UnblamedHunk {
+            range_in_blamed_file: 4..15,
+            range_in_destination: 5..16
+        })
+    );
+    assert_eq!(change, None);
+    assert_eq!(lines_blamed, vec![]);
+    assert_eq!(new_hunks_to_blame, vec![]);
+    assert_eq!(offset_in_destination, Offset::Added(0));
+}
+
 #[test]
 fn process_change_works_unchanged_hunk() {
     let mut lines_blamed: Vec<BlameEntry> = vec![];