diff: simplify color_moved check when flushing

In diff_flush_patch_all_file_pairs(), we set o->emitted_symbols if and
only if o->color_moved is true. That causes the lower-level routines to
fill up o->emitted_symbols, which we then analyze in order to do the
actual colorizing.

But in that final step, we do:

  if (o->emitted_symbols) {
          if (o->color_moved) {
	     ...actual coloring...
	  }
	  ...clean up of emitted_symbols...
  }

The inner "if" will always trigger, since we set emitted_symbols only
when doing color_moved (it is a little confusing that it is set inside
the diff_options struct, but that is for convenience of passing it to
the lower-level routines; we always clear it at the end of flushing,
since 48edf3a (diff: clear emitted_symbols flag after use,
2019-01-24)).

Let's simplify the code a bit by just dropping the inner "if" and
running its block unconditionally.

In theory the current code might be useful if another feature besides
color_moved setup and used emitted_symbols, but it would be easy to
refactor later to handle that. And in the meantime, this makes further
work in this area easier.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: peff

diff.c

@@ -6690,20 +6690,17 @@ static void diff_flush_patch_all_file_pairs(struct diff_options *o)
 	}
 
 	if (o->emitted_symbols) {
-		if (o->color_moved) {
-			struct mem_pool entry_pool;
-			struct moved_entry_list *entry_list;
-
-			mem_pool_init(&entry_pool, 1024 * 1024);
-			entry_list = add_lines_to_move_detection(o,
-								 &entry_pool);
-			mark_color_as_moved(o, entry_list);
-			if (o->color_moved == COLOR_MOVED_ZEBRA_DIM)
-				dim_moved_lines(o);
-
-			mem_pool_discard(&entry_pool, 0);
-			free(entry_list);
-		}
+		struct mem_pool entry_pool;
+		struct moved_entry_list *entry_list;
+
+		mem_pool_init(&entry_pool, 1024 * 1024);
+		entry_list = add_lines_to_move_detection(o, &entry_pool);
+		mark_color_as_moved(o, entry_list);
+		if (o->color_moved == COLOR_MOVED_ZEBRA_DIM)
+			dim_moved_lines(o);
+
+		mem_pool_discard(&entry_pool, 0);
+		free(entry_list);
 
 		for (i = 0; i < esm.nr; i++)
 			emit_diff_symbol_from_struct(o, &esm.buf[i]);