graph: add truncation mark to capped lanes
When lanes are hidden by --graph-lane-limit, show a "~" truncation mark, so users know that there are lanes being truncated. The "~" is chosen because it is not used elsewhere in the graph and it is discrete. Signed-off-by: Pablo Sabater <pabloosabaterr@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Pablo Sabater committed
Mar 28, 2026 at 01:11 UTC
9bab3ce5553b2333b8f8ee1aff27a9fe6a938f65
3 files changed
+52
-39
Documentation/rev-list-options.adoc
+3
-2
index d530e744f6..94a7b1c065 100644
--- a/Documentation/rev-list-options.adoc
+++ b/Documentation/rev-list-options.adoc
@@ -1261,8 +1261,9 @@ This implies the `--topo-order` option by default, but the
`--graph-lane-limit=<n>`::
When `--graph` is used, limit the number of graph lanes to be shown.
- Lanes over the limit are not shown. By default it is set to 0
- (no limit), zero and negative values are ignored and treated as no limit.
+ Lanes over the limit are replaced with a truncation mark '~'.
+ By default it is set to 0 (no limit), zero and negative values
+ are ignored and treated as no limit.
ifdef::git-rev-list[]
`--count`::
graph.c
+17
-5
index ee1f9e2d2d..842282685f 100644
--- a/graph.c
+++ b/graph.c
@@ -706,11 +706,11 @@ static void graph_update_columns(struct git_graph *graph)
}
/*
- * If graph_max_lanes is set, cap the width
+ * If graph_max_lanes is set, cap the width
*/
if (graph->revs->graph_max_lanes > 0) {
/*
- * Width is column index while a lane is half that.
+ * width of "| " per lanes plus truncation mark "~ ".
* Allow commits from merges to align to the merged lane.
*/
int max_width = graph->revs->graph_max_lanes * 2 + 2;
@@ -868,8 +868,10 @@ static void graph_output_padding_line(struct git_graph *graph,
* Output a padding row, that leaves all branch lines unchanged
*/
for (i = 0; i < graph->num_new_columns; i++) {
- if (graph_needs_truncation(graph, i))
+ if (graph_needs_truncation(graph, i)) {
+ graph_line_addstr(line, "~ ");
break;
+ }
graph_line_write_column(line, &graph->new_columns[i], '|');
graph_line_addch(line, ' ');
}
@@ -928,6 +930,7 @@ static void graph_output_pre_commit_line(struct git_graph *graph,
graph_line_write_column(line, col, '|');
graph_line_addchars(line, ' ', graph->expansion_row);
} else if (seen_this && graph_needs_truncation(graph, i)) {
+ graph_line_addstr(line, "~ ");
break;
} else if (seen_this && (graph->expansion_row == 0)) {
/*
@@ -1025,8 +1028,10 @@ static void graph_draw_octopus_merge(struct git_graph *graph, struct graph_line
* Commit is at commit_index, each iteration move one lane to
* the right from the commit.
*/
- if (graph_needs_truncation(graph, graph->commit_index + 1 + i))
+ if (graph_needs_truncation(graph, graph->commit_index + 1 + i)) {
+ graph_line_addstr(line, "~ ");
break;
+ }
graph_line_write_column(line, col, (i == dashed_parents - 1) ? '.' : '-');
}
@@ -1070,6 +1075,7 @@ static void graph_output_commit_line(struct git_graph *graph, struct graph_line
if (graph->num_parents > 2)
graph_draw_octopus_merge(graph, line);
} else if (graph_needs_truncation(graph, i)) {
+ graph_line_addstr(line, "~ ");
seen_this = 1;
break;
} else if (seen_this && (graph->edges_added > 1)) {
@@ -1203,6 +1209,7 @@ static void graph_output_post_merge_line(struct git_graph *graph, struct graph_l
j / 2 + i <= graph->num_columns) {
if ((j + i * 2) % 2 != 0)
graph_line_addch(line, ' ');
+ graph_line_addstr(line, "~ ");
truncated = 1;
break;
}
@@ -1214,6 +1221,7 @@ static void graph_output_post_merge_line(struct git_graph *graph, struct graph_l
*/
if (graph_needs_truncation(graph, (j + 1) / 2 + i) &&
j < graph->num_parents - 1) {
+ graph_line_addstr(line, "~ ");
truncated = 1;
break;
} else if (graph->edges_added > 0 || j < graph->num_parents - 1)
@@ -1228,6 +1236,7 @@ static void graph_output_post_merge_line(struct git_graph *graph, struct graph_l
if (graph->edges_added == 0)
graph_line_addch(line, ' ');
} else if (graph_needs_truncation(graph, i)) {
+ graph_line_addstr(line, "~ ");
break;
} else if (seen_this) {
if (graph->edges_added > 0)
@@ -1388,6 +1397,7 @@ static void graph_output_collapsing_line(struct git_graph *graph, struct graph_l
int target = graph->mapping[i];
if (!truncated && graph_needs_truncation(graph, i / 2)) {
+ graph_line_addstr(line, "~ ");
truncated = 1;
}
@@ -1487,8 +1497,10 @@ 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];
- if (graph_needs_truncation(graph, i))
+ if (graph_needs_truncation(graph, i)) {
+ graph_line_addstr(&line, "~ ");
break;
+ }
graph_line_write_column(&line, col, '|');
t/t4215-log-skewed-merges.sh
+32
-32
index d7524e9366..1612f05f1b 100755
--- a/t/t4215-log-skewed-merges.sh
+++ b/t/t4215-log-skewed-merges.sh
@@ -376,9 +376,9 @@ test_expect_success 'log --graph --graph-lane-limit=2 limited to two lanes' '
|\ \
| | * 7_G
| | * 7_F
- | * 7_E
- | * 7_D
- * | 7_C
+ | * ~ 7_E
+ | * ~ 7_D
+ * | ~ 7_C
| |/
|/|
* | 7_B
@@ -389,16 +389,16 @@ test_expect_success 'log --graph --graph-lane-limit=2 limited to two lanes' '
test_expect_success 'log --graph --graph-lane-limit=1 truncate mid octopus merge' '
check_graph --graph-lane-limit=1 M_7 <<-\EOF
- *- 7_M4
- |\
- | 7_G
- | 7_F
+ *-~ 7_M4
+ |\~
+ | ~ 7_G
+ | ~ 7_F
| * 7_E
| * 7_D
- * 7_C
- |
- |/
- * 7_B
+ * ~ 7_C
+ | ~
+ |/~
+ * ~ 7_B
|/
* 7_A
EOF
@@ -411,24 +411,24 @@ test_expect_success 'log --graph --graph-lane-limit=3 limited to three lanes' '
| | * 7_M2
| | |\
| | | * 7_H
- | | | 7_M3
- | | | 7_J
- | | | 7_I
- | | | 7_M4
- | |_|_
- |/| |
- | | |_
- | |/|
- | | |
- | | |/
- | | * 7_G
- | | |
- | | |/
- | | * 7_F
- | * | 7_E
- | | |/
- | |/|
- | * | 7_D
+ | | | ~ 7_M3
+ | | | ~ 7_J
+ | | | ~ 7_I
+ | | | ~ 7_M4
+ | |_|_~
+ |/| | ~
+ | | |_~
+ | |/| ~
+ | | | ~
+ | | |/~
+ | | * ~ 7_G
+ | | | ~
+ | | |/~
+ | | * ~ 7_F
+ | * | ~ 7_E
+ | | |/~
+ | |/| ~
+ | * | ~ 7_D
| | |/
| |/|
* | | 7_C
@@ -452,9 +452,9 @@ test_expect_success 'log --graph --graph-lane-limit=6 check if it only shows fir
| | | | | * 7_J
| | | | * | 7_I
| | | | | | * 7_M4
- | |_|_|_|_|/
- |/| | | | |/
- | | |_|_|/|
+ | |_|_|_|_|/~
+ |/| | | | |/~
+ | | |_|_|/| ~
| |/| | | |/
| | | |_|/|
| | |/| | |