am --skip: revert changes introduced by failed 3way merge
Even when a merge conflict occurs with am --3way, the index will be modified with the results of any succesfully merged files (such as a new file). These changes to the index will not be reverted with a "git read-tree --reset -u HEAD HEAD", as git read-tree will not be aware of how the current index differs from HEAD. To fix this, we first reset any conflicting entries from the index. The resulting index will contain the results of successfully merged files. We write the index to a tree, then use git read-tree -m to fast-forward the "index tree" back to HEAD, thus undoing all the changes from the failed merge. Signed-off-by: Paul Tan <pyokagan@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Paul Tan committed
Jun 6, 2015 at 19:46 UTC
88d5072466de2e0ba256a283eaaa6a79e31735a5
2 files changed
+17
-1
git-am.sh
+6
-1
@@ -68,6 +68,8 @@ then
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cmdline="$cmdline -3"
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fi
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+empty_tree=4b825dc642cb6eb9a060e54bf8d69288fbee4904
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+
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sq () {
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git rev-parse --sq-quote "$@"
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}
@@ -492,7 +494,10 @@ then
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;;
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t,)
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git rerere clear
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- git read-tree --reset -u HEAD HEAD
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+ head_tree=$(git rev-parse --verify -q HEAD || echo $empty_tree) &&
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+ git read-tree --reset -u $head_tree $head_tree &&
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+ index_tree=$(git write-tree) &&
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+ git read-tree -m -u $index_tree $head_tree
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orig_head=$(cat "$GIT_DIR/ORIG_HEAD")
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git reset HEAD
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git update-ref ORIG_HEAD $orig_head
t/t4151-am-abort.sh
+11
@@ -63,6 +63,17 @@ do
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done
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+test_expect_success 'am -3 --skip removes otherfile-4' '
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+ git reset --hard initial &&
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+ test_must_fail git am -3 0003-*.patch &&
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+ test 3 -eq $(git ls-files -u | wc -l) &&
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+ test 4 = "$(cat otherfile-4)" &&
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+ git am --skip &&
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+ test_cmp_rev initial HEAD &&
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+ test -z $(git ls-files -u) &&
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+ test_path_is_missing otherfile-4
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+'
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+
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test_expect_success 'am --abort will keep the local commits intact' '
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test_must_fail git am 0004-*.patch &&
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test_commit unrelated &&