[PATCH v2] submodule: Demonstrate known breakage during recursive merge
From: Brad King <hidden>
Date: 2016-06-15 22:51:55
Subsystem:
the rest · Maintainer:
Linus Torvalds
Since commit 68d03e4a (Implement automatic fast-forward merge for
submodules, 2010-07-07) we try to suggest submodule commits that resolve
a conflict. Consider a true recursive merge case
b---bc
/ \ /
o X
\ / \
c---cb
in which the two heads themselves (bc,cb) had resolved a submodule
conflict (i.e. reference different commits than their parents). The
submodule merge search runs during the temporary merge of the two merge
bases (b,c) and prints out a suggestion that is not meaningful to the
user. Then during the main merge the submodule merge search runs again
but dies with the message
fatal: --ancestry-path given but there are no bottom commits
while trying to enumerate candidates. Demonstrate this known breakage
with a new test in t7405-submodule-merge covering the case.
Signed-off-by: Brad King <redacted>
---
This fixes the first version of the patch by using "merge --no-commit"
instead of "merge -n" where the intention is to not commit the merge.
Both instances are followed by a submodule checkout, add, and then a
real commit. Now the history in the test actually looks like what
is in the commit message.
Brad
t/t7405-submodule-merge.sh | 51 ++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 51 insertions(+), 0 deletions(-)
diff --git a/t/t7405-submodule-merge.sh b/t/t7405-submodule-merge.sh
index a8fb30b..14da2e3 100755
--- a/t/t7405-submodule-merge.sh
+++ b/t/t7405-submodule-merge.sh@@ -228,4 +228,55 @@ test_expect_success 'merging with a modify/modify conflict between merge bases' git merge d ' +# canonical criss-cross history in top and submodule +test_expect_success 'setup for recursive merge with submodule' ' + mkdir merge-recursive && + (cd merge-recursive && + git init && + mkdir sub && + (cd sub && + git init && + test_commit a && + git checkout -b sub-b master && + test_commit b && + git checkout -b sub-c master && + test_commit c && + git checkout -b sub-bc sub-b && + git merge sub-c && + git checkout -b sub-cb sub-c && + git merge sub-b && + git checkout master) && + git add sub && + git commit -m a && + git checkout -b top-b master && + (cd sub && git checkout sub-b) && + git add sub && + git commit -m b && + git checkout -b top-c master && + (cd sub && git checkout sub-c) && + git add sub && + git commit -m c && + git checkout -b top-bc top-b && + git merge -s ours --no-commit top-c && + (cd sub && git checkout sub-bc) && + git add sub && + git commit -m bc && + git checkout -b top-cb top-c && + git merge -s ours --no-commit top-b && + (cd sub && git checkout sub-cb) && + git add sub && + git commit -m cb) +' + +# merge should leave submodule unmerged in index +test_expect_failure 'recursive merge with submodule' ' + (cd merge-recursive && + test_must_fail git merge top-bc && + echo "160000 $(git rev-parse top-cb:sub) 2 sub" > expect2 && + echo "160000 $(git rev-parse top-bc:sub) 3 sub" > expect3 && + git ls-files -u > actual && + grep "$(cat expect2)" actual > /dev/null && + grep "$(cat expect3)" actual > /dev/null) +' + test_done
--
1.7.4.4