For octopus merges where the first parent edge immediately merges into
the next column to the left:
| *-.
| |\ \
|/ / /
then the number of columns should be one less than the usual case:
| *-.
| |\ \
| | | *
Also refactor the code to iterate over columns rather than dashes,
building from an initial patch suggestion by Jeff King.
Signed-off-by: Noam Postavsky <npostavs@xxxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Jeff King <peff@xxxxxxxx>
---
graph.c | 56 +++++++++++++++++-------
t/t4214-log-graph-octopus.sh | 102 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 143 insertions(+), 15 deletions(-)
create mode 100755 t/t4214-log-graph-octopus.sh
diff --git a/graph.c b/graph.c
index e1f6d3bddb..a3366f6dac 100644
--- a/graph.c
+++ b/graph.c
@@ -842,27 +842,53 @@ static void graph_output_commit_char(struct git_graph *graph, struct strbuf *sb)
}
/*
- * Draw an octopus merge and return the number of characters written.
+ * Draw the horizontal dashes of an octopus merge and return the number of
+ * characters written.
*/
static int graph_draw_octopus_merge(struct git_graph *graph,
struct strbuf *sb)
{
/*
- * Here dashless_commits represents the number of parents
- * which don't need to have dashes (because their edges fit
- * neatly under the commit).
- */
- const int dashless_commits = 2;
- int col_num, i;
- int num_dashes =
- ((graph->num_parents - dashless_commits) * 2) - 1;
- for (i = 0; i < num_dashes; i++) {
- col_num = (i / 2) + dashless_commits + graph->commit_index;
- strbuf_write_column(sb, &graph->new_columns[col_num], '-');
+ * Here dashless_parents represents the number of parents which don't
+ * need to have dashes (the edges labeled "0" and "1"). And
+ * dashful_parents are the remaining ones.
+ *
+ * | *---.
+ * | |\ \ \
+ * | | | | |
+ * x 0 1 2 3
+ *
+ */
+ const int dashless_parents = 2;
+ int dashful_parents = graph->num_parents - dashless_parents;
+
+ /*
+ * Usually, each parent gets its own column, like the diagram above, but
+ * sometimes the first parent goes into an existing column, like this:
+ *
+ * | *---.
+ * | |\ \ \
+ * |/ / / /
+ * x 0 1 2
+ *
+ * In which case there will be more parents than the delta of columns.
+ */
+ int delta_cols = (graph->num_new_columns - graph->num_columns);
+ int parent_in_old_cols = graph->num_parents - delta_cols;
+
+ /*
+ * In both cases, commit_index corresponds to the edge labeled "0".
+ */
+ int first_col = graph->commit_index + dashless_parents
+ - parent_in_old_cols;
+
+ int i;
+ for (i = 0; i < dashful_parents; i++) {
+ strbuf_write_column(sb, &graph->new_columns[i+first_col], '-');
+ strbuf_write_column(sb, &graph->new_columns[i+first_col],
+ i == dashful_parents-1 ? '.' : '-');
}
- col_num = (i / 2) + dashless_commits + graph->commit_index;
- strbuf_write_column(sb, &graph->new_columns[col_num], '.');
- return num_dashes + 1;
+ return 2 * dashful_parents;
}
static void graph_output_commit_line(struct git_graph *graph, struct strbuf *sb)
diff --git a/t/t4214-log-graph-octopus.sh b/t/t4214-log-graph-octopus.sh
new file mode 100755
index 0000000000..dab96c89aa
--- /dev/null
+++ b/t/t4214-log-graph-octopus.sh
@@ -0,0 +1,102 @@
+#!/bin/sh
+
+test_description='git log --graph of skewed left octopus merge.'
+
+. ./test-lib.sh
+
+test_expect_success 'set up merge history' '
+ cat >expect.uncolored <<-\EOF &&
+ * left
+ | *---. octopus-merge
+ | |\ \ \
+ |/ / / /
+ | | | * 4
+ | | * | 3
+ | | |/
+ | * | 2
+ | |/
+ * | 1
+ |/
+ * initial
+ EOF
+ cat >expect.colors <<-\EOF &&
+ * left
+ <RED>|<RESET> *<BLUE>-<RESET><BLUE>-<RESET><MAGENTA>-<RESET><MAGENTA>.<RESET> octopus-merge
+ <RED>|<RESET> <RED>|<RESET><YELLOW>\<RESET> <BLUE>\<RESET> <MAGENTA>\<RESET>
+ <RED>|<RESET><RED>/<RESET> <YELLOW>/<RESET> <BLUE>/<RESET> <MAGENTA>/<RESET>
+ <RED>|<RESET> <YELLOW>|<RESET> <BLUE>|<RESET> * 4
+ <RED>|<RESET> <YELLOW>|<RESET> * <MAGENTA>|<RESET> 3
+ <RED>|<RESET> <YELLOW>|<RESET> <MAGENTA>|<RESET><MAGENTA>/<RESET>
+ <RED>|<RESET> * <MAGENTA>|<RESET> 2
+ <RED>|<RESET> <MAGENTA>|<RESET><MAGENTA>/<RESET>
+ * <MAGENTA>|<RESET> 1
+ <MAGENTA>|<RESET><MAGENTA>/<RESET>
+ * initial
+ EOF
+ test_commit initial &&
+ for i in 1 2 3 4 ; do
+ git checkout master -b $i || return $?
+ # Make tag name different from branch name, to avoid
+ # ambiguity error when calling checkout.
+ test_commit $i $i $i tag$i || return $?
+ done &&
+ git checkout 1 -b merge &&
+ test_tick &&
+ git merge -m octopus-merge 1 2 3 4 &&
+ git checkout 1 -b L &&
+ test_commit left
+'
+
+test_expect_success 'log --graph with tricky octopus merge with colors' '
+ test_config log.graphColors red,green,yellow,blue,magenta,cyan &&
+ git log --color=always --graph --date-order --pretty=tformat:%s --all >actual.colors.raw &&
+ test_decode_color <actual.colors.raw | sed "s/ *\$//" >actual.colors &&
+ test_cmp expect.colors actual.colors
+'
+
+test_expect_success 'log --graph with tricky octopus merge, no color' '
+ git log --color=never --graph --date-order --pretty=tformat:%s --all >actual.raw &&
+ sed "s/ *\$//" actual.raw >actual &&
+ test_cmp expect.uncolored actual
+'
+
+# Repeat the previous two tests with "normal" octopus merge (i.e.,
+# without the first parent skewing to the "left" branch column).
+
+test_expect_success 'log --graph with normal octopus merge, no color' '
+ cat >expect.uncolored <<-\EOF &&
+ *---. octopus-merge
+ |\ \ \
+ | | | * 4
+ | | * | 3
+ | | |/
+ | * | 2
+ | |/
+ * | 1
+ |/
+ * initial
+ EOF
+ git log --color=never --graph --date-order --pretty=tformat:%s merge >actual.raw &&
+ sed "s/ *\$//" actual.raw >actual &&
+ test_cmp expect.uncolored actual
+'
+
+test_expect_success 'log --graph with normal octopus merge with colors' '
+ cat >expect.colors <<-\EOF &&
+ *<YELLOW>-<RESET><YELLOW>-<RESET><BLUE>-<RESET><BLUE>.<RESET> octopus-merge
+ <RED>|<RESET><GREEN>\<RESET> <YELLOW>\<RESET> <BLUE>\<RESET>
+ <RED>|<RESET> <GREEN>|<RESET> <YELLOW>|<RESET> * 4
+ <RED>|<RESET> <GREEN>|<RESET> * <BLUE>|<RESET> 3
+ <RED>|<RESET> <GREEN>|<RESET> <BLUE>|<RESET><BLUE>/<RESET>
+ <RED>|<RESET> * <BLUE>|<RESET> 2
+ <RED>|<RESET> <BLUE>|<RESET><BLUE>/<RESET>
+ * <BLUE>|<RESET> 1
+ <BLUE>|<RESET><BLUE>/<RESET>
+ * initial
+ EOF
+ test_config log.graphColors red,green,yellow,blue,magenta,cyan &&
+ git log --color=always --graph --date-order --pretty=tformat:%s merge >actual.colors.raw &&
+ test_decode_color <actual.colors.raw | sed "s/ *\$//" >actual.colors &&
+ test_cmp expect.colors actual.colors
+'
+test_done
--
2.11.0
