graph: fix extra spaces in graph_padding_line
authorJeff King <peff@peff.net>
Thu, 29 Sep 2016 08:37:51 +0000 (04:37 -0400)
committerJunio C Hamano <gitster@pobox.com>
Thu, 29 Sep 2016 23:43:47 +0000 (16:43 -0700)
The graph_padding_line() function outputs a series of "|"
columns, and then pads with spaces to graph->width by
calling graph_pad_horizontally(). However, we tell the
latter that we wrote graph->num_columns characters, which is
not true; we also needed spaces between the columns. Let's
keep a count of how many characters we've written, which is
what all the other callers of graph_pad_horizontally() do.

Without this, any output that is written at the end of a
padding line will be bumped out by at least an extra
graph->num_columns spaces. Presumably nobody ever noticed
the bug because there's no code path that actually writes to
the end of a padding line.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
graph.c
diff --git a/graph.c b/graph.c
index 1350bdde3be4346e8bc2038c57e4883d0ab12b25..5ad62b8a83d77a8f2cccf87f94a3240977ddb0f0 100644 (file)
--- a/graph.c
+++ b/graph.c
@@ -1138,6 +1138,7 @@ int graph_next_line(struct git_graph *graph, struct strbuf *sb)
 static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
 {
        int i;
+       int chars_written = 0;
 
        if (graph->state != GRAPH_COMMIT) {
                graph_next_line(graph, sb);
@@ -1153,14 +1154,21 @@ static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
         */
        for (i = 0; i < graph->num_columns; i++) {
                struct column *col = &graph->columns[i];
+
                strbuf_write_column(sb, col, '|');
-               if (col->commit == graph->commit && graph->num_parents > 2)
-                       strbuf_addchars(sb, ' ', (graph->num_parents - 2) * 2);
-               else
+               chars_written++;
+
+               if (col->commit == graph->commit && graph->num_parents > 2) {
+                       int len = (graph->num_parents - 2) * 2;
+                       strbuf_addchars(sb, ' ', len);
+                       chars_written += len;
+               } else {
                        strbuf_addch(sb, ' ');
+                       chars_written++;
+               }
        }
 
-       graph_pad_horizontally(graph, sb, graph->num_columns);
+       graph_pad_horizontally(graph, sb, chars_written);
 
        /*
         * Update graph->prev_state since we have output a padding line