histedit: render a rolled up description using the proper roll colours
Users have rightfully complained that the old behaviour of completely
removing the description of a rolled commit makes it difficult to
remember what was in that commit. Instead, we now render the removed
description in red.
I couldn't think of a simpler way to do this. You can't just combine
existing curses colours into new effects; only secondary effects like
bold or underline can be logically OR'ed to generate a combined text
effect. It seems easier to just redundantly keep track of what the
roll colour should be.
#testcases bdiff xdiff
#if xdiff
#require xdiff
$ cat >> $HGRCPATH <<EOF
> [experimental]
> xdiff = true
> EOF
#endif
Test case that makes use of the weakness of patience diff algorithm
$ hg init
>>> open('a', 'wb').write(('\n'.join(list('a' + 'x' * 10 + 'u' + 'x' * 30 + 'a\n'))).encode('ascii')) and None
$ hg commit -m 1 -A a
>>> open('a', 'wb').write(('\n'.join(list('b' + 'x' * 30 + 'u' + 'x' * 10 + 'b\n'))).encode('ascii')) and None
#if xdiff
$ hg diff
diff -r f0aeecb49805 a
--- a/a Thu Jan 01 00:00:00 1970 +0000
+++ b/a Thu Jan 01 00:00:00 1970 +0000
@@ -1,4 +1,4 @@
-a
+b
x
x
x
@@ -9,7 +9,6 @@
x
x
x
-u
x
x
x
@@ -30,6 +29,7 @@
x
x
x
+u
x
x
x
@@ -40,5 +40,5 @@
x
x
x
-a
+b
#else
$ hg diff
diff -r f0aeecb49805 a
--- a/a Thu Jan 01 00:00:00 1970 +0000
+++ b/a Thu Jan 01 00:00:00 1970 +0000
@@ -1,15 +1,4 @@
-a
-x
-x
-x
-x
-x
-x
-x
-x
-x
-x
-u
+b
x
x
x
@@ -40,5 +29,16 @@
x
x
x
-a
+u
+x
+x
+x
+x
+x
+x
+x
+x
+x
+x
+b
#endif