[PATCH v4 2/4] Adjust stat width calculations to take --graph output into account

[Lucian Poston <lucian.poston@gmail.com>]

The recent change to compute the width of diff --stat did not take into
consideration the output from --graph. The consequence is that when both
options are used, e.g. in 'log --stat --graph', the lines are too long.

Add output_prefix_length to diff_options. Initialize the value to 0 and only
set it when graph.c:diff_output_prefix_callback() is called.

Using output_prefix_length, adjust stat width calculations to take --graph
output into account.

t4052: Modify tests to verify that diff stat output is adjusted to compenstate
for the history graph tree.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
---
 diff.c                 |    2 +-
 diff.h                 |    1 +
 graph.c                |    3 +++
 t/t4052-stat-output.sh |   34 +++++++++++++++++++++++++---------
 4 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/diff.c b/diff.c
index 377ec1e..0b61cf7 100644
--- a/diff.c
+++ b/diff.c
@@ -1445,7 +1445,7 @@ static void show_stats(struct diffstat_t *data, struct diff_options *options)
 	 */
 
 	if (options->stat_width == -1)
-		width = term_columns();
+		width = term_columns() - options->output_prefix_length;
 	else
 		width = options->stat_width ? options->stat_width : 80;
 
diff --git a/diff.h b/diff.h
index cb68743..19d762f 100644
--- a/diff.h
+++ b/diff.h
@@ -150,6 +150,7 @@ struct diff_options {
 	diff_format_fn_t format_callback;
 	void *format_callback_data;
 	diff_prefix_fn_t output_prefix;
+	int output_prefix_length;
 	void *output_prefix_data;
 };
 
diff --git a/graph.c b/graph.c
index 7358416..7e0a099 100644
--- a/graph.c
+++ b/graph.c
@@ -194,8 +194,10 @@ static struct strbuf *diff_output_prefix_callback(struct diff_options *opt, void
 	struct git_graph *graph = data;
 	static struct strbuf msgbuf = STRBUF_INIT;
 
+	assert(opt);
 	assert(graph);
 
+	opt->output_prefix_length = graph->width;
 	strbuf_reset(&msgbuf);
 	graph_padding_line(graph, &msgbuf);
 	return &msgbuf;
@@ -245,6 +247,7 @@ struct git_graph *graph_init(struct rev_info *opt)
 	 */
 	opt->diffopt.output_prefix = diff_output_prefix_callback;
 	opt->diffopt.output_prefix_data = graph;
+	opt->diffopt.output_prefix_length = 0;
 
 	return graph;
 }
diff --git a/t/t4052-stat-output.sh b/t/t4052-stat-output.sh
index da14984..d748e5e 100755
--- a/t/t4052-stat-output.sh
+++ b/t/t4052-stat-output.sh
@@ -89,7 +89,7 @@ cat >expect200 <<'EOF'
  abcd | 1000 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 EOF
 cat >expect200-graph <<'EOF'
-|  abcd | 1000 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+|  abcd | 1000 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 EOF
 while read verb expect cmd args
 do
@@ -117,7 +117,7 @@ cat >expect40 <<'EOF'
  abcd | 1000 ++++++++++++++++++++++++++
 EOF
 cat >expect40-graph <<'EOF'
-|  abcd | 1000 ++++++++++++++++++++++++++
+|  abcd | 1000 ++++++++++++++++++++++++
 EOF
 while read verb expect cmd args
 do
@@ -127,12 +127,6 @@ do
 		test_cmp "$expect" actual
 	'
 
-	test_expect_success "$cmd $verb statGraphWidth config" '
-		git -c diff.statGraphWidth=26 $cmd $args >output
-		grep " | " output >actual &&
-		test_cmp "$expect" actual
-	'
-
 	test "$cmd" != diff || continue
 
 	test_expect_success "$cmd --graph $verb not enough COLUMNS (big change)" '
@@ -140,6 +134,28 @@ do
 		grep " | " output >actual &&
 		test_cmp "$expect-graph" actual
 	'
+done <<\EOF
+ignores expect80 format-patch -1 --stdout
+respects expect40 diff HEAD^ HEAD --stat
+respects expect40 show --stat
+respects expect40 log -1 --stat
+EOF
+
+cat >expect40 <<'EOF'
+ abcd | 1000 ++++++++++++++++++++++++++
+EOF
+cat >expect40-graph <<'EOF'
+|  abcd | 1000 ++++++++++++++++++++++++++
+EOF
+while read verb expect cmd args
+do
+	test_expect_success "$cmd $verb statGraphWidth config" '
+		git -c diff.statGraphWidth=26 $cmd $args >output
+		grep " | " output >actual &&
+		test_cmp "$expect" actual
+	'
+
+	test "$cmd" != diff || continue
 
 	test_expect_success "$cmd --graph $verb statGraphWidth config" '
 		git -c diff.statGraphWidth=26 $cmd $args --graph >output
@@ -244,7 +260,7 @@ cat >expect200 <<'EOF'
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa | 1000 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 EOF
 cat >expect200-graph <<'EOF'
-|  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa | 1000 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+|  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa | 1000 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 EOF
 while read verb expect cmd args
 do
-- 
1.7.3.4