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index b8741416588e9f3d7de7c0a0359a0b8ea7cf8045..dfee7d159b3b5198b4773f2d3869e809095b11f7 100755 (executable)
#!/bin/sh
-test_description='recursive merge corner cases'
+test_description='recursive merge corner cases involving criss-cross merges'
. ./test-lib.sh
+get_clean_checkout () {
+ git reset --hard &&
+ git clean -fdqx &&
+ git checkout "$1"
+}
+
#
# L1 L2
# o---o
# R1 R2
#
-test_expect_success setup '
+test_expect_success 'setup basic criss-cross + rename with no modifications' '
+ ten="0 1 2 3 4 5 6 7 8 9" &&
+ for i in $ten
+ do
+ echo line $i in a sample file
+ done >one &&
+ for i in $ten
+ do
+ echo line $i in another sample file
+ done >two &&
+ git add one two &&
+ test_tick && git commit -m initial &&
+
+ git branch L1 &&
+ git checkout -b R1 &&
+ git mv one three &&
+ test_tick && git commit -m R1 &&
+
+ git checkout L1 &&
+ git mv two three &&
+ test_tick && git commit -m L1 &&
+
+ git checkout L1^0 &&
+ test_tick && git merge -s ours R1 &&
+ git tag L2 &&
+
+ git checkout R1^0 &&
+ test_tick && git merge -s ours L1 &&
+ git tag R2
+'
+
+test_expect_success 'merge simple rename+criss-cross with no modifications' '
+ git reset --hard &&
+ git checkout L2^0 &&
+
+ test_must_fail git merge -s recursive R2^0 &&
+
+ test 2 = $(git ls-files -s | wc -l) &&
+ test 2 = $(git ls-files -u | wc -l) &&
+ test 2 = $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse :2:three) = $(git rev-parse L2:three) &&
+ test $(git rev-parse :3:three) = $(git rev-parse R2:three) &&
+
+ test $(git rev-parse L2:three) = $(git hash-object three~HEAD) &&
+ test $(git rev-parse R2:three) = $(git hash-object three~R2^0)
+'
+
+#
+# Same as before, but modify L1 slightly:
+#
+# L1m L2
+# o---o
+# / \ / \
+# o X ?
+# \ / \ /
+# o---o
+# R1 R2
+#
+
+test_expect_success 'setup criss-cross + rename merges with basic modification' '
+ git rm -rf . &&
+ git clean -fdqx &&
+ rm -rf .git &&
+ git init &&
+
ten="0 1 2 3 4 5 6 7 8 9"
for i in $ten
do
git branch L1 &&
git checkout -b R1 &&
git mv one three &&
+ echo more >>two &&
+ git add two &&
test_tick && git commit -m R1 &&
git checkout L1 &&
git tag R2
'
-test_expect_success merge '
+test_expect_success 'merge criss-cross + rename merges with basic modification' '
git reset --hard &&
git checkout L2^0 &&
- test_must_fail git merge -s recursive R2^0
+ test_must_fail git merge -s recursive R2^0 &&
+
+ test 2 = $(git ls-files -s | wc -l) &&
+ test 2 = $(git ls-files -u | wc -l) &&
+ test 2 = $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse :2:three) = $(git rev-parse L2:three) &&
+ test $(git rev-parse :3:three) = $(git rev-parse R2:three) &&
+
+ test $(git rev-parse L2:three) = $(git hash-object three~HEAD) &&
+ test $(git rev-parse R2:three) = $(git hash-object three~R2^0)
+'
+
+#
+# For the next test, we start with three commits in two lines of development
+# which setup a rename/add conflict:
+# Commit A: File 'a' exists
+# Commit B: Rename 'a' -> 'new_a'
+# Commit C: Modify 'a', create different 'new_a'
+# Later, two different people merge and resolve differently:
+# Commit D: Merge B & C, ignoring separately created 'new_a'
+# Commit E: Merge B & C making use of some piece of secondary 'new_a'
+# Finally, someone goes to merge D & E. Does git detect the conflict?
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+
+test_expect_success 'setup differently handled merges of rename/add conflict' '
+ git rm -rf . &&
+ git clean -fdqx &&
+ rm -rf .git &&
+ git init &&
+
+ printf "0\n1\n2\n3\n4\n5\n6\n7\n8\n9\n" >a &&
+ git add a &&
+ test_tick && git commit -m A &&
+
+ git branch B &&
+ git checkout -b C &&
+ echo 10 >>a &&
+ echo "other content" >>new_a &&
+ git add a new_a &&
+ test_tick && git commit -m C &&
+
+ git checkout B &&
+ git mv a new_a &&
+ test_tick && git commit -m B &&
+
+ git checkout B^0 &&
+ test_must_fail git merge C &&
+ git clean -f &&
+ test_tick && git commit -m D &&
+ git tag D &&
+
+ git checkout C^0 &&
+ test_must_fail git merge B &&
+ rm new_a~HEAD new_a &&
+ printf "Incorrectly merged content" >>new_a &&
+ git add -u &&
+ test_tick && git commit -m E &&
+ git tag E
+'
+
+test_expect_success 'git detects differently handled merges conflict' '
+ git reset --hard &&
+ git checkout D^0 &&
+
+ git merge -s recursive E^0 && {
+ echo "BAD: should have conflicted"
+ test "Incorrectly merged content" = "$(cat new_a)" &&
+ echo "BAD: Silently accepted wrong content"
+ return 1
+ }
+
+ test 3 = $(git ls-files -s | wc -l) &&
+ test 3 = $(git ls-files -u | wc -l) &&
+ test 0 = $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse :2:new_a) = $(git rev-parse D:new_a) &&
+ test $(git rev-parse :3:new_a) = $(git rev-parse E:new_a) &&
+
+ git cat-file -p B:new_a >>merged &&
+ git cat-file -p C:new_a >>merge-me &&
+ >empty &&
+ test_must_fail git merge-file \
+ -L "Temporary merge branch 2" \
+ -L "" \
+ -L "Temporary merge branch 1" \
+ merged empty merge-me &&
+ test $(git rev-parse :1:new_a) = $(git hash-object merged)
+'
+
+#
+# criss-cross + modify/delete:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: file with contents 'A\n'
+# Commit B: file with contents 'B\n'
+# Commit C: file not present
+# Commit D: file with contents 'B\n'
+# Commit E: file not present
+#
+# Merging commits D & E should result in modify/delete conflict.
+
+test_expect_success 'setup criss-cross + modify/delete resolved differently' '
+ git rm -rf . &&
+ git clean -fdqx &&
+ rm -rf .git &&
+ git init &&
+
+ echo A >file &&
+ git add file &&
+ test_tick &&
+ git commit -m A &&
+
+ git branch B &&
+ git checkout -b C &&
+ git rm file &&
+ test_tick &&
+ git commit -m C &&
+
+ git checkout B &&
+ echo B >file &&
+ git add file &&
+ test_tick &&
+ git commit -m B &&
+
+ git checkout B^0 &&
+ test_must_fail git merge C &&
+ echo B >file &&
+ git add file &&
+ test_tick &&
+ git commit -m D &&
+ git tag D &&
+
+ git checkout C^0 &&
+ test_must_fail git merge B &&
+ git rm file &&
+ test_tick &&
+ git commit -m E &&
+ git tag E
+'
+
+test_expect_success 'git detects conflict merging criss-cross+modify/delete' '
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ test 2 -eq $(git ls-files -s | wc -l) &&
+ test 2 -eq $(git ls-files -u | wc -l) &&
+
+ test $(git rev-parse :1:file) = $(git rev-parse master:file) &&
+ test $(git rev-parse :2:file) = $(git rev-parse B:file)
+'
+
+test_expect_success 'git detects conflict merging criss-cross+modify/delete, reverse direction' '
+ git reset --hard &&
+ git checkout E^0 &&
+
+ test_must_fail git merge -s recursive D^0 &&
+
+ test 2 -eq $(git ls-files -s | wc -l) &&
+ test 2 -eq $(git ls-files -u | wc -l) &&
+
+ test $(git rev-parse :1:file) = $(git rev-parse master:file) &&
+ test $(git rev-parse :3:file) = $(git rev-parse B:file)
+'
+
+#
+# criss-cross + modify/modify with very contrived file contents:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: file with contents 'A\n'
+# Commit B: file with contents 'B\n'
+# Commit C: file with contents 'C\n'
+# Commit D: file with contents 'D\n'
+# Commit E: file with contents:
+# <<<<<<< Temporary merge branch 1
+# C
+# =======
+# B
+# >>>>>>> Temporary merge branch 2
+#
+# Now, when we merge commits D & E, does git detect the conflict?
+
+test_expect_success 'setup differently handled merges of content conflict' '
+ git clean -fdqx &&
+ rm -rf .git &&
+ git init &&
+
+ echo A >file &&
+ git add file &&
+ test_tick &&
+ git commit -m A &&
+
+ git branch B &&
+ git checkout -b C &&
+ echo C >file &&
+ git add file &&
+ test_tick &&
+ git commit -m C &&
+
+ git checkout B &&
+ echo B >file &&
+ git add file &&
+ test_tick &&
+ git commit -m B &&
+
+ git checkout B^0 &&
+ test_must_fail git merge C &&
+ echo D >file &&
+ git add file &&
+ test_tick &&
+ git commit -m D &&
+ git tag D &&
+
+ git checkout C^0 &&
+ test_must_fail git merge B &&
+ cat <<EOF >file &&
+<<<<<<< Temporary merge branch 1
+C
+=======
+B
+>>>>>>> Temporary merge branch 2
+EOF
+ git add file &&
+ test_tick &&
+ git commit -m E &&
+ git tag E
+'
+
+test_expect_failure 'git detects conflict w/ criss-cross+contrived resolution' '
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ test 3 -eq $(git ls-files -s | wc -l) &&
+ test 3 -eq $(git ls-files -u | wc -l) &&
+ test 0 -eq $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse :2:file) = $(git rev-parse D:file) &&
+ test $(git rev-parse :3:file) = $(git rev-parse E:file)
+'
+
+#
+# criss-cross + d/f conflict via add/add:
+# Commit A: Neither file 'a' nor directory 'a/' exist.
+# Commit B: Introduce 'a'
+# Commit C: Introduce 'a/file'
+# Commit D: Merge B & C, keeping 'a' and deleting 'a/'
+#
+# Two different later cases:
+# Commit E1: Merge B & C, deleting 'a' but keeping 'a/file'
+# Commit E2: Merge B & C, deleting 'a' but keeping a slightly modified 'a/file'
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E1 or E2
+#
+# Merging D & E1 requires we first create a virtual merge base X from
+# merging A & B in memory. Now, if X could keep both 'a' and 'a/file' in
+# the index, then the merge of D & E1 could be resolved cleanly with both
+# 'a' and 'a/file' removed. Since git does not currently allow creating
+# such a tree, the best we can do is have X contain both 'a~<unique>' and
+# 'a/file' resulting in the merge of D and E1 having a rename/delete
+# conflict for 'a'. (Although this merge appears to be unsolvable with git
+# currently, git could do a lot better than it currently does with these
+# d/f conflicts, which is the purpose of this test.)
+#
+# Merge of D & E2 has similar issues for path 'a', but should always result
+# in a modify/delete conflict for path 'a/file'.
+#
+# We run each merge in both directions, to check for directional issues
+# with D/F conflict handling.
+#
+
+test_expect_success 'setup differently handled merges of directory/file conflict' '
+ git rm -rf . &&
+ git clean -fdqx &&
+ rm -rf .git &&
+ git init &&
+
+ >ignore-me &&
+ git add ignore-me &&
+ test_tick &&
+ git commit -m A &&
+ git tag A &&
+
+ git branch B &&
+ git checkout -b C &&
+ mkdir a &&
+ echo 10 >a/file &&
+ git add a/file &&
+ test_tick &&
+ git commit -m C &&
+
+ git checkout B &&
+ echo 5 >a &&
+ git add a &&
+ test_tick &&
+ git commit -m B &&
+
+ git checkout B^0 &&
+ test_must_fail git merge C &&
+ git clean -f &&
+ rm -rf a/ &&
+ echo 5 >a &&
+ git add a &&
+ test_tick &&
+ git commit -m D &&
+ git tag D &&
+
+ git checkout C^0 &&
+ test_must_fail git merge B &&
+ git clean -f &&
+ git rm --cached a &&
+ echo 10 >a/file &&
+ git add a/file &&
+ test_tick &&
+ git commit -m E1 &&
+ git tag E1 &&
+
+ git checkout C^0 &&
+ test_must_fail git merge B &&
+ git clean -f &&
+ git rm --cached a &&
+ printf "10\n11\n" >a/file &&
+ git add a/file &&
+ test_tick &&
+ git commit -m E2 &&
+ git tag E2
+'
+
+test_expect_success 'merge of D & E1 fails but has appropriate contents' '
+ get_clean_checkout D^0 &&
+
+ test_must_fail git merge -s recursive E1^0 &&
+
+ test 2 -eq $(git ls-files -s | wc -l) &&
+ test 1 -eq $(git ls-files -u | wc -l) &&
+ test 0 -eq $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
+ test $(git rev-parse :2:a) = $(git rev-parse B:a)
+'
+
+test_expect_success 'merge of E1 & D fails but has appropriate contents' '
+ get_clean_checkout E1^0 &&
+
+ test_must_fail git merge -s recursive D^0 &&
+
+ test 2 -eq $(git ls-files -s | wc -l) &&
+ test 1 -eq $(git ls-files -u | wc -l) &&
+ test 0 -eq $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
+ test $(git rev-parse :3:a) = $(git rev-parse B:a)
+'
+
+test_expect_success 'merge of D & E2 fails but has appropriate contents' '
+ get_clean_checkout D^0 &&
+
+ test_must_fail git merge -s recursive E2^0 &&
+
+ test 4 -eq $(git ls-files -s | wc -l) &&
+ test 3 -eq $(git ls-files -u | wc -l) &&
+ test 1 -eq $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse :2:a) = $(git rev-parse B:a) &&
+ test $(git rev-parse :3:a/file) = $(git rev-parse E2:a/file) &&
+ test $(git rev-parse :1:a/file) = $(git rev-parse C:a/file) &&
+ test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
+
+ test -f a~HEAD
+'
+
+test_expect_success 'merge of E2 & D fails but has appropriate contents' '
+ get_clean_checkout E2^0 &&
+
+ test_must_fail git merge -s recursive D^0 &&
+
+ test 4 -eq $(git ls-files -s | wc -l) &&
+ test 3 -eq $(git ls-files -u | wc -l) &&
+ test 1 -eq $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse :3:a) = $(git rev-parse B:a) &&
+ test $(git rev-parse :2:a/file) = $(git rev-parse E2:a/file) &&
+ test $(git rev-parse :1:a/file) = $(git rev-parse C:a/file)
+ test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
+
+ test -f a~D^0
+'
+
+#
+# criss-cross with rename/rename(1to2)/modify followed by
+# rename/rename(2to1)/modify:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: new file: a
+# Commit B: rename a->b, modifying by adding a line
+# Commit C: rename a->c
+# Commit D: merge B&C, resolving conflict by keeping contents in newname
+# Commit E: merge B&C, resolving conflict similar to D but adding another line
+#
+# There is a conflict merging B & C, but one of filename not of file
+# content. Whoever created D and E chose specific resolutions for that
+# conflict resolution. Now, since: (1) there is no content conflict
+# merging B & C, (2) D does not modify that merged content further, and (3)
+# both D & E resolve the name conflict in the same way, the modification to
+# newname in E should not cause any conflicts when it is merged with D.
+# (Note that this can be accomplished by having the virtual merge base have
+# the merged contents of b and c stored in a file named a, which seems like
+# the most logical choice anyway.)
+#
+# Comment from Junio: I do not necessarily agree with the choice "a", but
+# it feels sound to say "B and C do not agree what the final pathname
+# should be, but we know this content was derived from the common A:a so we
+# use one path whose name is arbitrary in the virtual merge base X between
+# D and E" and then further let the rename detection to notice that that
+# arbitrary path gets renamed between X-D to "newname" and X-E also to
+# "newname" to resolve it as both sides renaming it to the same new
+# name. It is akin to what we do at the content level, i.e. "B and C do not
+# agree what the final contents should be, so we leave the conflict marker
+# but that may cancel out at the final merge stage".
+
+test_expect_success 'setup rename/rename(1to2)/modify followed by what looks like rename/rename(2to1)/modify' '
+ git reset --hard &&
+ git rm -rf . &&
+ git clean -fdqx &&
+ rm -rf .git &&
+ git init &&
+
+ printf "1\n2\n3\n4\n5\n6\n" >a &&
+ git add a &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ git mv a b &&
+ echo 7 >>b &&
+ git add -u &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ git mv a c &&
+ git commit -m C &&
+
+ git checkout -q B^0 &&
+ git merge --no-commit -s ours C^0 &&
+ git mv b newname &&
+ git commit -m "Merge commit C^0 into HEAD" &&
+ git tag D &&
+
+ git checkout -q C^0 &&
+ git merge --no-commit -s ours B^0 &&
+ git mv c newname &&
+ printf "7\n8\n" >>newname &&
+ git add -u &&
+ git commit -m "Merge commit B^0 into HEAD" &&
+ git tag E
+'
+
+test_expect_success 'handle rename/rename(1to2)/modify followed by what looks like rename/rename(2to1)/modify' '
+ git checkout D^0 &&
+
+ git merge -s recursive E^0 &&
+
+ test 1 -eq $(git ls-files -s | wc -l) &&
+ test 0 -eq $(git ls-files -u | wc -l) &&
+ test 0 -eq $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse HEAD:newname) = $(git rev-parse E:newname)
+'
+
+#
+# criss-cross with rename/rename(1to2)/add-source + resolvable modify/modify:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: new file: a
+# Commit B: rename a->b
+# Commit C: rename a->c, add different a
+# Commit D: merge B&C, keeping b&c and (new) a modified at beginning
+# Commit E: merge B&C, keeping b&c and (new) a modified at end
+#
+# Merging commits D & E should result in no conflict; doing so correctly
+# requires getting the virtual merge base (from merging B&C) right, handling
+# renaming carefully (both in the virtual merge base and later), and getting
+# content merge handled.
+
+test_expect_success 'setup criss-cross + rename/rename/add + modify/modify' '
+ git rm -rf . &&
+ git clean -fdqx &&
+ rm -rf .git &&
+ git init &&
+
+ printf "lots\nof\nwords\nand\ncontent\n" >a &&
+ git add a &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ git mv a b &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ git mv a c &&
+ printf "2\n3\n4\n5\n6\n7\n" >a &&
+ git add a &&
+ git commit -m C &&
+
+ git checkout B^0 &&
+ git merge --no-commit -s ours C^0 &&
+ git checkout C -- a c &&
+ mv a old_a &&
+ echo 1 >a &&
+ cat old_a >>a &&
+ rm old_a &&
+ git add -u &&
+ git commit -m "Merge commit C^0 into HEAD" &&
+ git tag D &&
+
+ git checkout C^0 &&
+ git merge --no-commit -s ours B^0 &&
+ git checkout B -- b &&
+ echo 8 >>a &&
+ git add -u &&
+ git commit -m "Merge commit B^0 into HEAD" &&
+ git tag E
+'
+
+test_expect_failure 'detect rename/rename/add-source for virtual merge-base' '
+ git checkout D^0 &&
+
+ git merge -s recursive E^0 &&
+
+ test 3 -eq $(git ls-files -s | wc -l) &&
+ test 0 -eq $(git ls-files -u | wc -l) &&
+ test 0 -eq $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse HEAD:b) = $(git rev-parse A:a) &&
+ test $(git rev-parse HEAD:c) = $(git rev-parse A:a) &&
+ test "$(cat a)" = "$(printf "1\n2\n3\n4\n5\n6\n7\n8\n")"
+'
+
+#
+# criss-cross with rename/rename(1to2)/add-dest + simple modify:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: new file: a
+# Commit B: rename a->b, add c
+# Commit C: rename a->c
+# Commit D: merge B&C, keeping A:a and B:c
+# Commit E: merge B&C, keeping A:a and slightly modified c from B
+#
+# Merging commits D & E should result in no conflict. The virtual merge
+# base of B & C needs to not delete B:c for that to work, though...
+
+test_expect_success 'setup criss-cross+rename/rename/add-dest + simple modify' '
+ git rm -rf . &&
+ git clean -fdqx &&
+ rm -rf .git &&
+ git init &&
+
+ >a &&
+ git add a &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ git mv a b &&
+ printf "1\n2\n3\n4\n5\n6\n7\n" >c &&
+ git add c &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ git mv a c &&
+ git commit -m C &&
+
+ git checkout B^0 &&
+ git merge --no-commit -s ours C^0 &&
+ git mv b a &&
+ git commit -m "D is like B but renames b back to a" &&
+ git tag D &&
+
+ git checkout B^0 &&
+ git merge --no-commit -s ours C^0 &&
+ git mv b a &&
+ echo 8 >>c &&
+ git add c &&
+ git commit -m "E like D but has mod in c" &&
+ git tag E
+'
+
+test_expect_success 'virtual merge base handles rename/rename(1to2)/add-dest' '
+ git checkout D^0 &&
+
+ git merge -s recursive E^0 &&
+
+ test 2 -eq $(git ls-files -s | wc -l) &&
+ test 0 -eq $(git ls-files -u | wc -l) &&
+ test 0 -eq $(git ls-files -o | wc -l) &&
+
+ test $(git rev-parse HEAD:a) = $(git rev-parse A:a) &&
+ test $(git rev-parse HEAD:c) = $(git rev-parse E:c)
'
test_done