diff kitten: Show overall diff stats

kittens/diff/collect.py

@@ -29,6 +29,7 @@ class Collection:
         self.removes = set()
         self.all_paths = []
         self.type_map = {}
+        self.added_count = self.removed_count = 0
 
     def add_change(self, left_path, right_path):
         self.changes[left_path] = right_path
@@ -44,11 +45,15 @@ class Collection:
         self.adds.add(right_path)
         self.all_paths.append(right_path)
         self.type_map[right_path] = 'add'
+        if isinstance(data_for_path(right_path), str):
+            self.added_count += len(lines_for_path(right_path))
 
     def add_removal(self, left_path):
         self.removes.add(left_path)
         self.all_paths.append(left_path)
         self.type_map[left_path] = 'removal'
+        if isinstance(data_for_path(left_path), str):
+            self.removed_count += len(lines_for_path(left_path))
 
     def finalize(self):
         self.all_paths.sort(key=path_name_map.get)

kittens/diff/main.py

@@ -68,6 +68,13 @@ class DiffHandler(Handler):
     def generate_diff(self):
         self.start_job('diff', generate_diff, self.collection, self.current_context_count)
 
+    def calculate_statistics(self):
+        self.added_count = self.collection.added_count
+        self.removed_count = self.collection.removed_count
+        for patch in self.diff_map.values():
+            self.added_count += patch.added_count
+            self.removed_count += patch.removed_count
+
     def render_diff(self):
         self.diff_lines = tuple(render_diff(self.collection, self.diff_map, self.args, self.screen_size.cols, self.image_manager))
         self.ref_path_map = defaultdict(list)
@@ -223,10 +230,17 @@ class DiffHandler(Handler):
         self.draw_status_line()
 
     def draw_status_line(self):
+        if self.state < DIFFED:
+            return
         self.cmd.set_cursor_position(0, self.num_lines)
         self.cmd.clear_to_eol()
         scroll_frac = styled('{:.0%}'.format(self.scroll_pos / self.max_scroll_pos), fg=self.opts.margin_fg)
-        suffix = scroll_frac
+        counts = '{}{}{}'.format(
+                styled(str(self.added_count), fg=self.opts.highlight_added_bg),
+                styled(',', fg=self.opts.margin_fg),
+                styled(str(self.removed_count), fg=self.opts.highlight_removed_bg)
+        )
+        suffix = counts + '  ' + scroll_frac
         prefix = styled(':', fg=self.opts.margin_fg)
         filler = self.screen_size.cols - wcswidth(prefix) - wcswidth(suffix)
         text = '{}{}{}'.format(prefix, ' ' * filler, suffix)
@@ -308,6 +322,7 @@ class DiffHandler(Handler):
                 return
             self.state = DIFFED
             self.diff_map = diff_map
+            self.calculate_statistics()
             self.render_diff()
             self.scroll_pos = 0
             if self.restore_position is not None:

kittens/diff/patch.py

@@ -84,6 +84,7 @@ class Hunk:
         self.left_start -= 1  # 0-index
         self.right_start -= 1  # 0-index
         self.title = title
+        self.added_count = self.removed_count = 0
         self.chunks = []
         self.current_chunk = None
         self.largest_line_number = max(self.left_start + self.left_count, self.right_start + self.right_count)
@@ -115,10 +116,12 @@ class Hunk:
     def add_line(self):
         self.ensure_diff_chunk()
         self.current_chunk.add_line()
+        self.added_count += 1
 
     def remove_line(self):
         self.ensure_diff_chunk()
         self.current_chunk.remove_line()
+        self.removed_count += 1
 
     def context_line(self):
         self.ensure_context_chunk()
@@ -159,6 +162,8 @@ class Patch:
     def __init__(self, all_hunks):
         self.all_hunks = all_hunks
         self.largest_line_number = self.all_hunks[-1].largest_line_number if self.all_hunks else 0
+        self.added_count = sum(h.added_count for h in all_hunks)
+        self.removed_count = sum(h.removed_count for h in all_hunks)
 
     def __iter__(self):
         return iter(self.all_hunks)