7a1bcb251b
6 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Denton Liu
|
d784d978f6 |
t4215: use helper function to check output
When git commands are placed in the upstream of a pipe, their return codes are lost. In this particular case, it is especially bad since we are testing the intricacies of `git log --graph` behavior and if we hit an unexpected failure or segfault, we want to know this. Extract the common output checking logic into check_graph() where we redirect the output of git commands upstream of pipe into a file and have sed read from that file so that git failures are detected. This patch is best viewed with `--color-moved`. Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> |
||
|
James Coglan
|
92beecc136 |
graph: flatten edges that fuse with their right neighbor
When a merge commit is printed and its final parent is the same commit
that occupies the column to the right of the merge, this results in a
kink in the displayed edges:
* |
|\ \
| |/
| *
Graphs containing these shapes can be hard to read, as the expansion to
the right followed immediately by collapsing back to the left creates a
lot of zig-zagging edges, especially when many columns are present.
We can improve this by eliminating the zig-zag and having the merge's
final parent edge fuse immediately with its neighbor:
* |
|\|
| *
This reduces the horizontal width for the current commit by 2, and
requires one less row, making the graph display more compact. Taken in
combination with other graph-smoothing enhancements, it greatly
compresses the space needed to display certain histories:
*
|\
| * *
| |\ |\
| | * | *
| | | | |\
| | \ | | *
| *-. \ | * |
| |\ \ \ => |/|\|
|/ / / / | | *
| | | / | * |
| | |/ | |/
| | * * /
| * | |/
| |/ *
* |
|/
*
One of the test cases here cannot be correctly rendered in Git v2.23.0;
it produces this output following commit E:
| | *-. \ 5_E
| | |\ \ \
| |/ / / /
| | | / _
| |_|/
|/| |
The new implementation makes sure that the rightmost edge in this
history is not left dangling as above.
Signed-off-by: James Coglan <jcoglan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
|
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|
James Coglan
|
479db18bc0 |
graph: smooth appearance of collapsing edges on commit lines
When a graph contains edges that are in the process of collapsing to the
left, but those edges cross a commit line, the effect is that the edges
have a jagged appearance:
*
|\
| *
| \
*-. \
|\ \ \
| | * |
| * | |
| |/ /
* | |
|/ /
* |
|/
*
We already takes steps to smooth edges like this when they're expanding;
when an edge appears to the right of a merge commit marker on a
GRAPH_COMMIT line immediately following a GRAPH_POST_MERGE line, we
render it as a `\`:
* \
|\ \
| * \
| |\ \
We can make a similar improvement to collapsing edges, making them
easier to follow and giving the overall graph a feeling of increased
symmetry:
*
|\
| *
| \
*-. \
|\ \ \
| | * |
| * | |
| |/ /
* / /
|/ /
* /
|/
*
To do this, we introduce a new special case for edges on GRAPH_COMMIT
lines that immediately follow a GRAPH_COLLAPSING line. By retaining a
copy of the `mapping` array used to render the GRAPH_COLLAPSING line in
the `old_mapping` array, we can determine that an edge is collapsing
through the GRAPH_COMMIT line and should be smoothed.
Signed-off-by: James Coglan <jcoglan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
|
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|
James Coglan
|
d62893ecc1 |
graph: commit and post-merge lines for left-skewed merges
Following the introduction of "left-skewed" merges, which are merges
whose first parent fuses with another edge to its left, we have some
more edge cases to deal with in the display of commit and post-merge
lines.
The current graph code handles the following cases for edges appearing
to the right of the commit (*) on commit lines. A 2-way merge is usually
followed by vertical lines:
| | |
| * |
| |\ \
An octopus merge (more than two parents) is always followed by edges
sloping to the right:
| | \ | | \
| *-. \ | *---. \
| |\ \ \ | |\ \ \ \
A 2-way merge is followed by a right-sloping edge if the commit line
immediately follows a post-merge line for a commit that appears in the
same column as the current commit, or any column to the left of that:
| * | * |
| |\ | |\ \
| * \ | | * \
| |\ \ | | |\ \
This commit introduces the following new cases for commit lines. If a
2-way merge skews to the left, then the edges to its right are always
vertical lines, even if the commit follows a post-merge line:
| | | | |\
| * | | * |
|/| | |/| |
A commit with 3 parents that skews left is followed by vertical edges:
| | |
| * |
|/|\ \
If a 3-way left-skewed merge commit appears immediately after a
post-merge line, then it may be followed the right-sloping edges, just
like a 2-way merge that is not skewed.
| |\
| * \
|/|\ \
Octopus merges with 4 or more parents that skew to the left will always
be followed by right-sloping edges, because the existing columns need to
expand around the merge.
| | \
| *-. \
|/|\ \ \
On post-merge lines, usually all edges following the current commit
slope to the right:
| * | |
| |\ \ \
However, if the commit is a left-skewed 2-way merge, the edges to its
right remain vertical. We also need to display a space after the
vertical line descending from the commit marker, whereas this line would
normally be followed by a backslash.
| * | |
|/| | |
If a left-skewed merge has more than 2 parents, then the edges to its
right are still sloped as they bend around the edges introduced by the
merge.
| * | |
|/|\ \ \
To handle these new cases, we need to know not just how many parents
each commit has, but how many new columns it adds to the display; this
quantity is recorded in the `edges_added` field for the current commit,
and `prev_edges_added` field for the previous commit.
Here, "column" refers to visual columns, not the logical columns of the
`columns` array. This is because even if all the commit's parents end up
fusing with existing edges, they initially introduce distinct edges in
the commit and post-merge lines before those edges collapse. For
example, a 3-way merge whose 2nd and 3rd parents fuse with existing
edges still introduces 2 visual columns that affect the display of edges
to their right.
| | | \
| | *-. \
| | |\ \ \
| |_|/ / /
|/| | / /
| | |/ /
| |/| |
| | | |
This merge does not introduce any *logical* columns; there are 4 edges
before and after this commit once all edges have collapsed. But it does
initially introduce 2 new edges that need to be accommodated by the
edges to their right.
Signed-off-by: James Coglan <jcoglan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
|
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|
James Coglan
|
0f0f389f12 |
graph: tidy up display of left-skewed merges
Currently, when we display a merge whose first parent is already present
in a column to the left of the merge commit, we display the first parent
as a vertical pipe `|` in the GRAPH_POST_MERGE line and then immediately
enter the GRAPH_COLLAPSING state. The first-parent line tracks to the
left and all the other parent lines follow it; this creates a "kink" in
those lines:
| *---.
| |\ \ \
|/ / / /
| | | *
This change tidies the display of such commits such that if the first
parent appears to the left of the merge, we render it as a `/` and the
second parent as a `|`. This reduces the horizontal and vertical space
needed to render the merge, and makes the resulting lines easier to
read.
| *-.
|/|\ \
| | | *
If the first parent is separated from the merge by several columns, a
horizontal line is drawn in a similar manner to how the GRAPH_COLLAPSING
state displays the line.
| | | *-.
| |_|/|\ \
|/| | | | *
This effect is applied to both "normal" two-parent merges, and to
octopus merges. It also reduces the vertical space needed for pre-commit
lines, as the merge occupies one less column than usual.
Before: After:
| * | *
| |\ | |\
| | \ | * \
| | \ |/|\ \
| *-. \
| |\ \ \
Signed-off-by: James Coglan <jcoglan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
|
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|
James Coglan
|
458152cce1 |
graph: example of graph output that can be simplified
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
Signed-off-by: James Coglan <jcoglan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
|