From 479db18bc0c38ed610fba56f3cc98abd7977e695 Mon Sep 17 00:00:00 2001
From: James Coglan <jcoglan@gmail.com>
Date: Tue, 15 Oct 2019 23:47:57 +0000
Subject: 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>
---
 t/t4214-log-graph-octopus.sh | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

(limited to 't/t4214-log-graph-octopus.sh')

diff --git a/t/t4214-log-graph-octopus.sh b/t/t4214-log-graph-octopus.sh
index 1b96276894..21bc600a82 100755
--- a/t/t4214-log-graph-octopus.sh
+++ b/t/t4214-log-graph-octopus.sh
@@ -31,9 +31,9 @@ test_expect_success 'log --graph with tricky octopus merge, no color' '
 	| | | * 4
 	| | * | 3
 	| | |/
-	| * | 2
+	| * / 2
 	| |/
-	* | 1
+	* / 1
 	|/
 	* initial
 	EOF
@@ -51,9 +51,9 @@ test_expect_success 'log --graph with tricky octopus merge with colors' '
 	<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> 2
 	<RED>|<RESET> <MAGENTA>|<RESET><MAGENTA>/<RESET>
-	* <MAGENTA>|<RESET> 1
+	* <MAGENTA>/<RESET> 1
 	<MAGENTA>|<RESET><MAGENTA>/<RESET>
 	* initial
 	EOF
@@ -72,9 +72,9 @@ test_expect_success 'log --graph with normal octopus merge, no color' '
 	| | | * 4
 	| | * | 3
 	| | |/
-	| * | 2
+	| * / 2
 	| |/
-	* | 1
+	* / 1
 	|/
 	* initial
 	EOF
@@ -90,9 +90,9 @@ test_expect_success 'log --graph with normal octopus merge with colors' '
 	<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> 2
 	<RED>|<RESET> <BLUE>|<RESET><BLUE>/<RESET>
-	* <BLUE>|<RESET> 1
+	* <BLUE>/<RESET> 1
 	<BLUE>|<RESET><BLUE>/<RESET>
 	* initial
 	EOF
@@ -110,9 +110,9 @@ test_expect_success 'log --graph with normal octopus merge and child, no color'
 	| | | * 4
 	| | * | 3
 	| | |/
-	| * | 2
+	| * / 2
 	| |/
-	* | 1
+	* / 1
 	|/
 	* initial
 	EOF
@@ -129,9 +129,9 @@ test_expect_failure 'log --graph with normal octopus and child merge with colors
 	<GREEN>|<RESET> <YELLOW>|<RESET> <BLUE>|<RESET> * 4
 	<GREEN>|<RESET> <YELLOW>|<RESET> * <MAGENTA>|<RESET> 3
 	<GREEN>|<RESET> <YELLOW>|<RESET> <MAGENTA>|<RESET><MAGENTA>/<RESET>
-	<GREEN>|<RESET> * <MAGENTA>|<RESET> 2
+	<GREEN>|<RESET> * <MAGENTA>/<RESET> 2
 	<GREEN>|<RESET> <MAGENTA>|<RESET><MAGENTA>/<RESET>
-	* <MAGENTA>|<RESET> 1
+	* <MAGENTA>/<RESET> 1
 	<MAGENTA>|<RESET><MAGENTA>/<RESET>
 	* initial
 	EOF
@@ -150,9 +150,9 @@ test_expect_success 'log --graph with tricky octopus merge and its child, no col
 	| | | * 4
 	| | * | 3
 	| | |/
-	| * | 2
+	| * / 2
 	| |/
-	* | 1
+	* / 1
 	|/
 	* initial
 	EOF
@@ -171,9 +171,9 @@ test_expect_failure 'log --graph with tricky octopus merge and its child with co
 	<RED>|<RESET> <BLUE>|<RESET> <MAGENTA>|<RESET> * 4
 	<RED>|<RESET> <BLUE>|<RESET> * <CYAN>|<RESET> 3
 	<RED>|<RESET> <BLUE>|<RESET> <CYAN>|<RESET><CYAN>/<RESET>
-	<RED>|<RESET> * <CYAN>|<RESET> 2
+	<RED>|<RESET> * <CYAN>/<RESET> 2
 	<RED>|<RESET> <CYAN>|<RESET><CYAN>/<RESET>
-	* <CYAN>|<RESET> 1
+	* <CYAN>/<RESET> 1
 	<CYAN>|<RESET><CYAN>/<RESET>
 	* initial
 	EOF
-- 
cgit v1.2.3