From: James Coglan <jcoglan@xxxxxxxxx>
The commits following this one introduce a series of improvements to the
layout of graphs, tidying up a few edge cases, namely:
- merge whose first parent fuses with an existing column to the left
- merge whose last parent fuses with its immediate neighbor on the right
- edges that collapse to the left above and below a commit line
This test case exemplifies these cases and provides a motivating example
of the kind of history I'm aiming to clear up.
The first parent of merge E is the same as the parent of H, so those
edges fuse together.
* H
|
| *-. E
| |\ \
|/ / /
|
* B
We can "skew" the display of this merge so that it doesn't introduce
additional columns that immediately collapse:
* H
|
| * E
|/|\
|
* B
The last parent of E is D, the same as the parent of F which is the edge
to the right of the merge.
* F
|
\
*-. \ E
|\ \ \
/ / / /
| /
|/
* D
The two edges leading to D could be fused sooner: rather than expanding
the F edge around the merge and then letting the edges collapse, the F
edge could fuse with the E edge in the post-merge line:
* F
|
\
*-. | E
|\ \|
/ / /
|
* D
If this is combined with the "skew" effect above, we get a much cleaner
graph display for these edges:
* F
|
* | E
/|\|
|
* D
Finally, the edge leading from C to A appears jagged as it passes
through the commit line for B:
| * | C
| |/
* | B
|/
* A
This can be smoothed out so that such edges are easier to read:
| * | C
| |/
* / B
|/
* A
---
t/t4215-log-skewed-merges.sh | 43 ++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
create mode 100755 t/t4215-log-skewed-merges.sh
diff --git a/t/t4215-log-skewed-merges.sh b/t/t4215-log-skewed-merges.sh
new file mode 100755
index 0000000000..4582ba066a
--- /dev/null
+++ b/t/t4215-log-skewed-merges.sh
@@ -0,0 +1,43 @@
+#!/bin/sh
+
+test_description='git log --graph of skewed merges'
+
+. ./test-lib.sh
+
+test_expect_success 'log --graph with merge fusing with its left and right neighbors' '
+ cat >expect <<-\EOF &&
+ * H
+ |\
+ | * G
+ | |\
+ | | * F
+ | | |
+ | | \
+ | *-. \ E
+ | |\ \ \
+ |/ / / /
+ | | | /
+ | | |/
+ | | * D
+ | * | C
+ | |/
+ * | B
+ |/
+ * A
+ EOF
+
+ git checkout --orphan _p &&
+ test_commit A &&
+ test_commit B &&
+ git checkout -b _q @^ && test_commit C &&
+ git checkout -b _r @^ && test_commit D &&
+ git checkout _p && git merge --no-ff _q _r -m E &&
+ git checkout _r && test_commit F &&
+ git checkout _p && git merge --no-ff _r -m G &&
+ git checkout @^^ && git merge --no-ff _p -m H &&
+
+ git log --graph --pretty=tformat:%s | sed "s/ *$//" >actual &&
+ test_cmp expect actual
+'
+
+test_done
--
gitgitgadget
