By default the git-format-patch command generates patches with prefixes
for the source and destination (-p1) and is also what git-am uses as a
default. The command strips the first leading path component when patch
is applied (unless a different -p<num> argument is used).
But the patch generating behaviour can be changed with git-format-patch
--no-prefix argument (or setting 'diff.noprefix = true' in .gitconfig).
Patches with no source and destination prefixes will confuse the git-am
3-way merge logic, since stripping the first path component will lead
to wrong paths for newly added files.
To avoid this, check that patches to apply are using git-format-patch's
defaults prefixes to make sure that git-am defaults are safe to use too.
Signed-off-by: Javier Martinez Canillas <javi...@redhat.com>
---
dim | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/dim b/dim
index bbe9308ac695..1a07cc177fb5 100755
--- a/dim
+++ b/dim
@@ -1113,6 +1113,18 @@ function check_merge_baseline
fi
}
+# ensure the patch has prefixes (-p1), since otherwise it can confuse the git
am
+# 3-way merge logic. check the default source (a/) and destination (b/)
prefixes.
+function check_diff_prefix
+{
+ local rv
+ patch="$1"
+
+ rv=$(grep -q -E "^diff --git a\/.+ b\/.+$" $patch)
+
+ return $rv
+}
+
# ensure we're on branch $1, and apply patches. the rest of the arguments are
# passed to git am.
dim_alias_ab=apply-branch
@@ -1139,6 +1151,13 @@ function dim_apply_branch
git mailsplit -b -o$dir $file > /dev/null
for patch in "$dir"/*; do
+
+ if ! check_diff_prefix "$patch"; then
+ echoerr "ERROR: The patch does not contain prefixes in
its diff."
+ echoerr "ERROR: This format can confuse git am when
applying it."
+ exit 1
+ fi
+
if ! apply_patch $patch "$@"; then
rv=1
fi
--
2.33.1
