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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 14:47:53 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 14:47:53 +0000
commitc8bae7493d2f2910b57f13ded012e86bdcfb0532 (patch)
tree24e09d9f84dec336720cf393e156089ca2835791 /t/t6416-recursive-corner-cases.sh
parentInitial commit. (diff)
downloadgit-c8bae7493d2f2910b57f13ded012e86bdcfb0532.tar.xz
git-c8bae7493d2f2910b57f13ded012e86bdcfb0532.zip
Adding upstream version 1:2.39.2.upstream/1%2.39.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 't/t6416-recursive-corner-cases.sh')
-rwxr-xr-xt/t6416-recursive-corner-cases.sh1885
1 files changed, 1885 insertions, 0 deletions
diff --git a/t/t6416-recursive-corner-cases.sh b/t/t6416-recursive-corner-cases.sh
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+#!/bin/sh
+
+test_description='recursive merge corner cases involving criss-cross merges'
+
+GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
+export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
+
+. ./test-lib.sh
+. "$TEST_DIRECTORY"/lib-merge.sh
+
+#
+# L1 L2
+# o---o
+# / \ / \
+# o X ?
+# \ / \ /
+# o---o
+# R1 R2
+#
+
+test_expect_success 'setup basic criss-cross + rename with no modifications' '
+ git init basic-rename &&
+ (
+ cd basic-rename &&
+
+ ten="0 1 2 3 4 5 6 7 8 9" &&
+ printf "line %d in a sample file\n" $ten >one &&
+ printf "line %d in another sample file\n" $ten >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' '
+ (
+ cd basic-rename &&
+
+ git reset --hard &&
+ git checkout L2^0 &&
+
+ test_must_fail git merge -s recursive R2^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 5 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ L2:three R2:three &&
+ git rev-parse >actual \
+ :2:three :3:three &&
+ test_cmp expect actual
+ )
+'
+
+#
+# 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 init rename-modify &&
+ (
+ cd rename-modify &&
+
+ ten="0 1 2 3 4 5 6 7 8 9" &&
+ printf "line %d in a sample file\n" $ten >one &&
+ printf "line %d in another sample file\n" $ten >two &&
+ git add one two &&
+ test_tick && git commit -m initial &&
+
+ 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 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 criss-cross + rename merges with basic modification' '
+ (
+ cd rename-modify &&
+
+ git checkout L2^0 &&
+
+ test_must_fail git merge -s recursive R2^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 5 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ L2:three R2:three &&
+ git rev-parse >actual \
+ :2:three :3:three &&
+ test_cmp expect actual
+ )
+'
+
+#
+# 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 init rename-add &&
+ (
+ cd rename-add &&
+
+ 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 &&
+ test_write_lines 0 1 2 3 4 5 6 7 foobar >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 show :2:new_a >new_a &&
+ git add new_a &&
+ test_tick && git commit -m D &&
+ git tag D &&
+
+ git checkout C^0 &&
+ test_must_fail git merge B &&
+ test_write_lines 0 1 2 3 4 5 6 7 bad_merge >new_a &&
+ git add -u &&
+ test_tick && git commit -m E &&
+ git tag E
+ )
+'
+
+test_expect_success 'git detects differently handled merges conflict' '
+ (
+ cd rename-add &&
+
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git cat-file -p C:new_a >ours &&
+ git cat-file -p C:a >theirs &&
+ >empty &&
+ test_must_fail git merge-file \
+ -L "Temporary merge branch 1" \
+ -L "" \
+ -L "Temporary merge branch 2" \
+ ours empty theirs &&
+ sed -e "s/^\([<=>]\)/\1\1\1/" ours >ours-tweaked &&
+ git hash-object ours-tweaked >expect &&
+ git rev-parse >>expect \
+ D:new_a E:new_a &&
+ git rev-parse >actual \
+ :1:new_a :2:new_a :3:new_a &&
+ test_cmp expect actual &&
+
+ # Test that the two-way merge in new_a is as expected
+ git cat-file -p D:new_a >ours &&
+ git cat-file -p E:new_a >theirs &&
+ >empty &&
+ test_must_fail git merge-file \
+ -L "HEAD" \
+ -L "" \
+ -L "E^0" \
+ ours empty theirs &&
+ sed -e "s/^\([<=>]\)/\1\1\1/" ours >expect &&
+ git hash-object new_a >actual &&
+ git hash-object ours >expect &&
+ test_cmp expect actual
+ )
+'
+
+# Repeat the above testcase with precisely the same setup, other than with
+# the two merge bases having different orderings of commit timestamps so
+# that they are reversed in the order they are provided to merge-recursive,
+# so that we can improve code coverage.
+test_expect_success 'git detects differently handled merges conflict, swapped' '
+ (
+ cd rename-add &&
+
+ # Difference #1: Do cleanup from previous testrun
+ git reset --hard &&
+ git clean -fdqx &&
+
+ # Difference #2: Change commit timestamps
+ btime=$(git log --no-walk --date=raw --format=%cd B | awk "{print \$1}") &&
+ ctime=$(git log --no-walk --date=raw --format=%cd C | awk "{print \$1}") &&
+ newctime=$(($btime+1)) &&
+ git fast-export --no-data --all | sed -e s/$ctime/$newctime/ | git fast-import --force --quiet &&
+ # End of most differences; rest is copy-paste of last test,
+ # other than swapping C:a and C:new_a due to order switch
+
+ git checkout D^0 &&
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git cat-file -p C:a >ours &&
+ git cat-file -p C:new_a >theirs &&
+ >empty &&
+ test_must_fail git merge-file \
+ -L "Temporary merge branch 1" \
+ -L "" \
+ -L "Temporary merge branch 2" \
+ ours empty theirs &&
+ sed -e "s/^\([<=>]\)/\1\1\1/" ours >ours-tweaked &&
+ git hash-object ours-tweaked >expect &&
+ git rev-parse >>expect \
+ D:new_a E:new_a &&
+ git rev-parse >actual \
+ :1:new_a :2:new_a :3:new_a &&
+ test_cmp expect actual &&
+
+ # Test that the two-way merge in new_a is as expected
+ git cat-file -p D:new_a >ours &&
+ git cat-file -p E:new_a >theirs &&
+ >empty &&
+ test_must_fail git merge-file \
+ -L "HEAD" \
+ -L "" \
+ -L "E^0" \
+ ours empty theirs &&
+ sed -e "s/^\([<=>]\)/\1\1\1/" ours >expect &&
+ git hash-object new_a >actual &&
+ git hash-object ours >expect &&
+ test_cmp expect actual
+ )
+'
+
+#
+# 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 init modify-delete &&
+ (
+ cd modify-delete &&
+
+ 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' '
+ (
+ cd modify-delete &&
+
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 2 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+
+ git rev-parse >expect \
+ main:file B:file &&
+ git rev-parse >actual \
+ :1:file :2:file &&
+ test_cmp expect actual
+ )
+'
+
+test_expect_success 'git detects conflict merging criss-cross+modify/delete, reverse direction' '
+ (
+ cd modify-delete &&
+
+ git reset --hard &&
+ git checkout E^0 &&
+
+ test_must_fail git merge -s recursive D^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 2 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+
+ git rev-parse >expect \
+ main:file B:file &&
+ git rev-parse >actual \
+ :1:file :3:file &&
+ test_cmp expect actual
+ )
+'
+
+# SORRY FOR THE SUPER LONG DESCRIPTION, BUT THIS NEXT ONE IS HAIRY
+#
+# criss-cross + d/f conflict via add/add:
+# Commit A: Neither file 'a' nor directory 'a/' exists.
+# Commit B: Introduce 'a'
+# Commit C: Introduce 'a/file'
+# Commit D1: Merge B & C, keeping 'a' and deleting 'a/'
+# Commit E1: Merge B & C, deleting 'a' but keeping 'a/file'
+#
+# B D1 or D2
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E1 or E2 or E3
+#
+# I'll describe D2, E2, & E3 (which are alternatives for D1 & E1) more below...
+#
+# Merging D1 & E1 requires we first create a virtual merge base X from
+# merging A & B in memory. There are several possibilities for the merge-base:
+# 1: Keep both 'a' and 'a/file' (assuming crazy filesystem allowing a tree
+# with a directory and file at same path): results in merge of D1 & E1
+# being clean with both files deleted. Bad (no conflict detected).
+# 2: Keep 'a' but not 'a/file': Merging D1 & E1 is clean and matches E1. Bad.
+# 3: Keep 'a/file' but not 'a': Merging D1 & E1 is clean and matches D1. Bad.
+# 4: Keep neither file: Merging D1 & E1 reports the D/F add/add conflict.
+#
+# So 4 sounds good for this case, but if we were to merge D1 & E3, where E3
+# is defined as:
+# Commit E3: Merge B & C, keeping modified a, and deleting a/
+# then we'd get an add/add conflict for 'a', which seems suboptimal. A little
+# creativity leads us to an alternate choice:
+# 5: Keep 'a' as 'a~$UNIQUE' and a/file; results:
+# Merge D1 & E1: rename/delete conflict for 'a'; a/file silently deleted
+# Merge D1 & E3 is clean, as expected.
+#
+# So choice 5 at least provides some kind of conflict for the original case,
+# and can merge cleanly as expected with D1 and E3. It also made things just
+# slightly funny for merging D1 and E4, where E4 is defined as:
+# Commit E4: Merge B & C, modifying 'a' and renaming to 'a2', and deleting 'a/'
+# in this case, we'll get a rename/rename(1to2) conflict because a~$UNIQUE
+# gets renamed to 'a' in D1 and to 'a2' in E4. But that's better than having
+# two files (both 'a' and 'a2') sitting around without the user being notified
+# that we could detect they were related and need to be merged. Also, choice
+# 5 makes the handling of 'a/file' seem suboptimal. What if we were to merge
+# D2 and E4, where D2 is:
+# Commit D2: Merge B & C, renaming 'a'->'a2', keeping 'a/file'
+# This would result in a clean merge with 'a2' having three-way merged
+# contents (good), and deleting 'a/' (bad) -- it doesn't detect the
+# conflict in how the different sides treated a/file differently.
+# Continuing down the creative route:
+# 6: Keep 'a' as 'a~$UNIQUE1' and keep 'a/' as 'a~$UNIQUE2/'; results:
+# Merge D1 & E1: rename/delete conflict for 'a' and each path under 'a/'.
+# Merge D1 & E3: clean, as expected.
+# Merge D1 & E4: rename/rename(1to2) conflict on 'a' vs 'a2'.
+# Merge D2 & E4: clean for 'a2', rename/delete for a/file
+#
+# Choice 6 could cause rename detection to take longer (providing more targets
+# that need to be searched). Also, the conflict message for each path under
+# 'a/' might be annoying unless we can detect it at the directory level, print
+# it once, and then suppress it for individual filepaths underneath.
+#
+#
+# As of time of writing, git uses choice 5. Directory rename detection and
+# rename detection performance improvements might make choice 6 a desirable
+# improvement. But we can at least document where we fall short for now...
+#
+#
+# Historically, this testcase also used:
+# Commit E2: Merge B & C, deleting 'a' but keeping slightly modified 'a/file'
+# The merge of D1 & E2 is very similar to D1 & E1 -- it has similar issues for
+# path 'a', but should always result in a modify/delete conflict for path
+# 'a/file'. These tests ran the two merges
+# D1 & E1
+# D1 & E2
+# in both directions, to check for directional issues with D/F conflict
+# handling. Later we added
+# D1 & E3
+# D1 & E4
+# D2 & E4
+# for good measure, though we only ran those one way because we had pretty
+# good confidence in merge-recursive's directional handling of D/F issues.
+#
+# Just to summarize all the intermediate merge commits:
+# Commit D1: Merge B & C, keeping a and deleting a/
+# Commit D2: Merge B & C, renaming a->a2, keeping a/file
+# Commit E1: Merge B & C, deleting a but keeping a/file
+# Commit E2: Merge B & C, deleting a but keeping slightly modified a/file
+# Commit E3: Merge B & C, keeping modified a, and deleting a/
+# Commit E4: Merge B & C, modifying 'a' and renaming to 'a2', and deleting 'a/'
+#
+
+test_expect_success 'setup differently handled merges of directory/file conflict' '
+ git init directory-file &&
+ (
+ cd directory-file &&
+
+ >ignore-me &&
+ git add ignore-me &&
+ test_tick &&
+ git commit -m A &&
+ git tag A &&
+
+ git branch B &&
+ git checkout -b C &&
+ mkdir a &&
+ test_write_lines a b c d e f g >a/file &&
+ git add a/file &&
+ test_tick &&
+ git commit -m C &&
+
+ git checkout B &&
+ test_write_lines 1 2 3 4 5 6 7 >a &&
+ git add a &&
+ test_tick &&
+ git commit -m B &&
+
+ git checkout B^0 &&
+ git merge -s ours -m D1 C^0 &&
+ git tag D1 &&
+
+ git checkout B^0 &&
+ test_must_fail git merge C^0 &&
+ if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+ then
+ git rm -rf a/ &&
+ git rm a~HEAD
+ else
+ git clean -fd &&
+ git rm -rf a/ &&
+ git rm a
+ fi &&
+ git cat-file -p B:a >a2 &&
+ git add a2 &&
+ git commit -m D2 &&
+ git tag D2 &&
+
+ git checkout C^0 &&
+ git merge -s ours -m E1 B^0 &&
+ git tag E1 &&
+
+ git checkout C^0 &&
+ git merge -s ours -m E2 B^0 &&
+ test_write_lines a b c d e f g h >a/file &&
+ git add a/file &&
+ git commit --amend -C HEAD &&
+ git tag E2 &&
+
+ git checkout C^0 &&
+ test_must_fail git merge B^0 &&
+ if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+ then
+ git rm a~B^0
+ else
+ git clean -fd
+ fi &&
+ git rm -rf a/ &&
+ test_write_lines 1 2 3 4 5 6 7 8 >a &&
+ git add a &&
+ git commit -m E3 &&
+ git tag E3 &&
+
+ git checkout C^0 &&
+ test_must_fail git merge B^0 &&
+ if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+ then
+ git rm -rf a/ &&
+ git rm a~B^0
+ else
+ git clean -fd &&
+ git rm -rf a/ &&
+ git rm a
+ fi &&
+ test_write_lines 1 2 3 4 5 6 7 8 >a2 &&
+ git add a2 &&
+ git commit -m E4 &&
+ git tag E4
+ )
+'
+
+test_expect_success 'merge of D1 & E1 fails but has appropriate contents' '
+ test_when_finished "git -C directory-file reset --hard" &&
+ test_when_finished "git -C directory-file clean -fdqx" &&
+ (
+ cd directory-file &&
+
+ git checkout D1^0 &&
+
+ test_must_fail git merge -s recursive E1^0 &&
+
+ if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+ then
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ A:ignore-me B:a D1:a &&
+ git rev-parse >actual \
+ :0:ignore-me :1:a :2:a &&
+ test_cmp expect actual
+ else
+ git ls-files -s >out &&
+ test_line_count = 2 out &&
+ git ls-files -u >out &&
+ test_line_count = 1 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ A:ignore-me B:a &&
+ git rev-parse >actual \
+ :0:ignore-me :2:a &&
+ test_cmp expect actual
+ fi
+ )
+'
+
+test_expect_success 'merge of E1 & D1 fails but has appropriate contents' '
+ test_when_finished "git -C directory-file reset --hard" &&
+ test_when_finished "git -C directory-file clean -fdqx" &&
+ (
+ cd directory-file &&
+
+ git checkout E1^0 &&
+
+ test_must_fail git merge -s recursive D1^0 &&
+
+ if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+ then
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ A:ignore-me B:a D1:a &&
+ git rev-parse >actual \
+ :0:ignore-me :1:a :3:a &&
+ test_cmp expect actual
+ else
+ git ls-files -s >out &&
+ test_line_count = 2 out &&
+ git ls-files -u >out &&
+ test_line_count = 1 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ A:ignore-me B:a &&
+ git rev-parse >actual \
+ :0:ignore-me :3:a &&
+ test_cmp expect actual
+ fi
+ )
+'
+
+test_expect_success 'merge of D1 & E2 fails but has appropriate contents' '
+ test_when_finished "git -C directory-file reset --hard" &&
+ test_when_finished "git -C directory-file clean -fdqx" &&
+ (
+ cd directory-file &&
+
+ git checkout D1^0 &&
+
+ test_must_fail git merge -s recursive E2^0 &&
+
+ if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+ then
+ git ls-files -s >out &&
+ test_line_count = 5 out &&
+ git ls-files -u >out &&
+ test_line_count = 4 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ B:a D1:a E2:a/file C:a/file A:ignore-me &&
+ git rev-parse >actual \
+ :1:a~HEAD :2:a~HEAD :3:a/file :1:a/file :0:ignore-me
+ else
+ git ls-files -s >out &&
+ test_line_count = 4 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 2 out &&
+
+ git rev-parse >expect \
+ B:a E2:a/file C:a/file A:ignore-me &&
+ git rev-parse >actual \
+ :2:a :3:a/file :1:a/file :0:ignore-me
+ fi &&
+ test_cmp expect actual &&
+
+ test_path_is_file a~HEAD
+ )
+'
+
+test_expect_success 'merge of E2 & D1 fails but has appropriate contents' '
+ test_when_finished "git -C directory-file reset --hard" &&
+ test_when_finished "git -C directory-file clean -fdqx" &&
+ (
+ cd directory-file &&
+
+ git checkout E2^0 &&
+
+ test_must_fail git merge -s recursive D1^0 &&
+
+ if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+ then
+ git ls-files -s >out &&
+ test_line_count = 5 out &&
+ git ls-files -u >out &&
+ test_line_count = 4 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ B:a D1:a E2:a/file C:a/file A:ignore-me &&
+ git rev-parse >actual \
+ :1:a~D1^0 :3:a~D1^0 :2:a/file :1:a/file :0:ignore-me
+ else
+ git ls-files -s >out &&
+ test_line_count = 4 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 2 out &&
+
+ git rev-parse >expect \
+ B:a E2:a/file C:a/file A:ignore-me &&
+ git rev-parse >actual \
+ :3:a :2:a/file :1:a/file :0:ignore-me
+ fi &&
+ test_cmp expect actual &&
+
+ test_path_is_file a~D1^0
+ )
+'
+
+test_expect_success 'merge of D1 & E3 succeeds' '
+ test_when_finished "git -C directory-file reset --hard" &&
+ test_when_finished "git -C directory-file clean -fdqx" &&
+ (
+ cd directory-file &&
+
+ git checkout D1^0 &&
+
+ git merge -s recursive E3^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 2 out &&
+ git ls-files -u >out &&
+ test_line_count = 0 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ A:ignore-me E3:a &&
+ git rev-parse >actual \
+ :0:ignore-me :0:a &&
+ test_cmp expect actual
+ )
+'
+
+test_expect_merge_algorithm failure success 'merge of D1 & E4 puts merge of a and a2 in both a and a2' '
+ test_when_finished "git -C directory-file reset --hard" &&
+ test_when_finished "git -C directory-file clean -fdqx" &&
+ (
+ cd directory-file &&
+
+ git checkout D1^0 &&
+
+ test_must_fail git merge -s recursive E4^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 4 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ A:ignore-me B:a E4:a2 E4:a2 &&
+ git rev-parse >actual \
+ :0:ignore-me :1:a~Temporary\ merge\ branch\ 2 :2:a :3:a2 &&
+ test_cmp expect actual
+ )
+'
+
+test_expect_failure 'merge of D2 & E4 merges a2s & reports conflict for a/file' '
+ test_when_finished "git -C directory-file reset --hard" &&
+ test_when_finished "git -C directory-file clean -fdqx" &&
+ (
+ cd directory-file &&
+
+ git checkout D2^0 &&
+
+ test_must_fail git merge -s recursive E4^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 1 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ A:ignore-me E4:a2 D2:a/file &&
+ git rev-parse >actual \
+ :0:ignore-me :0:a2 :2:a/file &&
+ test_cmp expect actual
+ )
+'
+
+#
+# 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 init rename-squared-squared &&
+ (
+ cd rename-squared-squared &&
+
+ 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' '
+ (
+ cd rename-squared-squared &&
+
+ git checkout D^0 &&
+
+ git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 1 out &&
+ git ls-files -u >out &&
+ test_line_count = 0 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ 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-source + modify/modify' '
+ git init rename-rename-add-source &&
+ (
+ cd rename-rename-add-source &&
+
+ 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' '
+ (
+ cd rename-rename-add-source &&
+
+ git checkout D^0 &&
+
+ git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 0 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ printf "1\n2\n3\n4\n5\n6\n7\n8\n" >correct &&
+ git rev-parse >expect \
+ A:a A:a \
+ correct &&
+ git rev-parse >actual \
+ :0:b :0:c &&
+ git hash-object >>actual \
+ a &&
+ test_cmp expect actual
+ )
+'
+
+#
+# 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 init rename-rename-add-dest &&
+ (
+ cd rename-rename-add-dest &&
+
+ >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' '
+ (
+ cd rename-rename-add-dest &&
+
+ git checkout D^0 &&
+
+ git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 2 out &&
+ git ls-files -u >out &&
+ test_line_count = 0 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ git rev-parse >expect \
+ A:a E:c &&
+ git rev-parse >actual \
+ :0:a :0:c &&
+ test_cmp expect actual
+ )
+'
+
+#
+# criss-cross with modify/modify on a symlink:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: simple simlink fickle->lagoon
+# Commit B: redirect fickle->disneyland
+# Commit C: redirect fickle->home
+# Commit D: merge B&C, resolving in favor of B
+# Commit E: merge B&C, resolving in favor of C
+#
+# This is an obvious modify/modify conflict for the symlink 'fickle'. Can
+# git detect it?
+
+test_expect_success 'setup symlink modify/modify' '
+ git init symlink-modify-modify &&
+ (
+ cd symlink-modify-modify &&
+
+ test_ln_s_add lagoon fickle &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ git rm fickle &&
+ test_ln_s_add disneyland fickle &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ git rm fickle &&
+ test_ln_s_add home fickle &&
+ git add fickle &&
+ git commit -m C &&
+
+ git checkout -q B^0 &&
+ git merge -s ours -m D C^0 &&
+ git tag D &&
+
+ git checkout -q C^0 &&
+ git merge -s ours -m E B^0 &&
+ git tag E
+ )
+'
+
+test_expect_merge_algorithm failure success 'check symlink modify/modify' '
+ (
+ cd symlink-modify-modify &&
+
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out
+ )
+'
+
+#
+# criss-cross with add/add of a symlink:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: No symlink or path exists yet
+# Commit B: set up symlink: fickle->disneyland
+# Commit C: set up symlink: fickle->home
+# Commit D: merge B&C, resolving in favor of B
+# Commit E: merge B&C, resolving in favor of C
+#
+# This is an obvious add/add conflict for the symlink 'fickle'. Can
+# git detect it?
+
+test_expect_success 'setup symlink add/add' '
+ git init symlink-add-add &&
+ (
+ cd symlink-add-add &&
+
+ touch ignoreme &&
+ git add ignoreme &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ test_ln_s_add disneyland fickle &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ test_ln_s_add home fickle &&
+ git add fickle &&
+ git commit -m C &&
+
+ git checkout -q B^0 &&
+ git merge -s ours -m D C^0 &&
+ git tag D &&
+
+ git checkout -q C^0 &&
+ git merge -s ours -m E B^0 &&
+ git tag E
+ )
+'
+
+test_expect_merge_algorithm failure success 'check symlink add/add' '
+ (
+ cd symlink-add-add &&
+
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out
+ )
+'
+
+#
+# criss-cross with modify/modify on a submodule:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: simple submodule repo
+# Commit B: update repo
+# Commit C: update repo differently
+# Commit D: merge B&C, resolving in favor of B
+# Commit E: merge B&C, resolving in favor of C
+#
+# This is an obvious modify/modify conflict for the submodule 'repo'. Can
+# git detect it?
+
+test_expect_success 'setup submodule modify/modify' '
+ git init submodule-modify-modify &&
+ (
+ cd submodule-modify-modify &&
+
+ git init submod &&
+ (
+ cd submod &&
+ touch file-A &&
+ git add file-A &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ touch file-B &&
+ git add file-B &&
+ git commit -m B &&
+ git tag B &&
+
+ git checkout -b C A &&
+ touch file-C &&
+ git add file-C &&
+ git commit -m C &&
+ git tag C
+ ) &&
+
+ git -C submod reset --hard A &&
+ git add submod &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ git -C submod reset --hard B &&
+ git add submod &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ git -C submod reset --hard C &&
+ git add submod &&
+ git commit -m C &&
+
+ git checkout -q B^0 &&
+ git merge -s ours -m D C^0 &&
+ git tag D &&
+
+ git checkout -q C^0 &&
+ git merge -s ours -m E B^0 &&
+ git tag E
+ )
+'
+
+test_expect_merge_algorithm failure success 'check submodule modify/modify' '
+ (
+ cd submodule-modify-modify &&
+
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out
+ )
+'
+
+#
+# criss-cross with add/add on a submodule:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: nothing of note
+# Commit B: introduce submodule repo
+# Commit C: introduce submodule repo at different commit
+# Commit D: merge B&C, resolving in favor of B
+# Commit E: merge B&C, resolving in favor of C
+#
+# This is an obvious add/add conflict for the submodule 'repo'. Can
+# git detect it?
+
+test_expect_success 'setup submodule add/add' '
+ git init submodule-add-add &&
+ (
+ cd submodule-add-add &&
+
+ git init submod &&
+ (
+ cd submod &&
+ touch file-A &&
+ git add file-A &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ touch file-B &&
+ git add file-B &&
+ git commit -m B &&
+ git tag B &&
+
+ git checkout -b C A &&
+ touch file-C &&
+ git add file-C &&
+ git commit -m C &&
+ git tag C
+ ) &&
+
+ touch irrelevant-file &&
+ git add irrelevant-file &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ git -C submod reset --hard B &&
+ git add submod &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ git -C submod reset --hard C &&
+ git add submod &&
+ git commit -m C &&
+
+ git checkout -q B^0 &&
+ git merge -s ours -m D C^0 &&
+ git tag D &&
+
+ git checkout -q C^0 &&
+ git merge -s ours -m E B^0 &&
+ git tag E
+ )
+'
+
+test_expect_merge_algorithm failure success 'check submodule add/add' '
+ (
+ cd submodule-add-add &&
+
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out
+ )
+'
+
+#
+# criss-cross with conflicting entry types:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: nothing of note
+# Commit B: introduce submodule 'path'
+# Commit C: introduce symlink 'path'
+# Commit D: merge B&C, resolving in favor of B
+# Commit E: merge B&C, resolving in favor of C
+#
+# This is an obvious add/add conflict for 'path'. Can git detect it?
+
+test_expect_success 'setup conflicting entry types (submodule vs symlink)' '
+ git init submodule-symlink-add-add &&
+ (
+ cd submodule-symlink-add-add &&
+
+ git init path &&
+ (
+ cd path &&
+ touch file-B &&
+ git add file-B &&
+ git commit -m B &&
+ git tag B
+ ) &&
+
+ touch irrelevant-file &&
+ git add irrelevant-file &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ git -C path reset --hard B &&
+ git add path &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ rm -rf path/ &&
+ test_ln_s_add irrelevant-file path &&
+ git commit -m C &&
+
+ git checkout -q B^0 &&
+ git merge -s ours -m D C^0 &&
+ git tag D &&
+
+ git checkout -q C^0 &&
+ git merge -s ours -m E B^0 &&
+ git tag E
+ )
+'
+
+test_expect_merge_algorithm failure success 'check conflicting entry types (submodule vs symlink)' '
+ (
+ cd submodule-symlink-add-add &&
+
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out
+ )
+'
+
+#
+# criss-cross with regular files that have conflicting modes:
+#
+# B D
+# o---o
+# / \ / \
+# A o X ? F
+# \ / \ /
+# o---o
+# C E
+#
+# Commit A: nothing of note
+# Commit B: introduce file source_me.bash, not executable
+# Commit C: introduce file source_me.bash, executable
+# Commit D: merge B&C, resolving in favor of B
+# Commit E: merge B&C, resolving in favor of C
+#
+# This is an obvious add/add mode conflict. Can git detect it?
+
+test_expect_success 'setup conflicting modes for regular file' '
+ git init regular-file-mode-conflict &&
+ (
+ cd regular-file-mode-conflict &&
+
+ touch irrelevant-file &&
+ git add irrelevant-file &&
+ git commit -m A &&
+ git tag A &&
+
+ git checkout -b B A &&
+ echo "command_to_run" >source_me.bash &&
+ git add source_me.bash &&
+ git commit -m B &&
+
+ git checkout -b C A &&
+ echo "command_to_run" >source_me.bash &&
+ git add source_me.bash &&
+ test_chmod +x source_me.bash &&
+ git commit -m C &&
+
+ git checkout -q B^0 &&
+ git merge -s ours -m D C^0 &&
+ git tag D &&
+
+ git checkout -q C^0 &&
+ git merge -s ours -m E B^0 &&
+ git tag E
+ )
+'
+
+test_expect_failure 'check conflicting modes for regular file' '
+ (
+ cd regular-file-mode-conflict &&
+
+ git checkout D^0 &&
+
+ test_must_fail git merge -s recursive E^0 &&
+
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+ git ls-files -o >out &&
+ test_line_count = 1 out
+ )
+'
+
+# Setup:
+# L1---L2
+# / \ / \
+# main X ?
+# \ / \ /
+# R1---R2
+#
+# Where:
+# main has two files, named 'b' and 'a'
+# branches L1 and R1 both modify each of the two files in conflicting ways
+#
+# L2 is a merge of R1 into L1; more on it later.
+# R2 is a merge of L1 into R1; more on it later.
+#
+# X is an auto-generated merge-base used when merging L2 and R2.
+# since X is a merge of L1 and R1, it has conflicting versions of each file
+#
+# More about L2 and R2:
+# - both resolve the conflicts in 'b' and 'a' differently
+# - L2 renames 'b' to 'm'
+# - R2 renames 'a' to 'm'
+#
+# In the end, in file 'm' we have four different conflicting files (from
+# two versions of 'b' and two of 'a'). In addition, if
+# merge.conflictstyle is diff3, then the base version also has
+# conflict markers of its own, leading to a total of three levels of
+# conflict markers. This is a pretty weird corner case, but we just want
+# to ensure that we handle it as well as practical.
+
+test_expect_success 'setup nested conflicts' '
+ git init nested_conflicts &&
+ (
+ cd nested_conflicts &&
+
+ # Create some related files now
+ printf "Random base content line %d\n" $(test_seq 1 10) >initial &&
+
+ cp initial b_L1 &&
+ cp initial b_R1 &&
+ cp initial b_L2 &&
+ cp initial b_R2 &&
+ cp initial a_L1 &&
+ cp initial a_R1 &&
+ cp initial a_L2 &&
+ cp initial a_R2 &&
+
+ test_write_lines b b_L1 >>b_L1 &&
+ test_write_lines b b_R1 >>b_R1 &&
+ test_write_lines b b_L2 >>b_L2 &&
+ test_write_lines b b_R2 >>b_R2 &&
+ test_write_lines a a_L1 >>a_L1 &&
+ test_write_lines a a_R1 >>a_R1 &&
+ test_write_lines a a_L2 >>a_L2 &&
+ test_write_lines a a_R2 >>a_R2 &&
+
+ # Setup original commit (or merge-base), consisting of
+ # files named "b" and "a"
+ cp initial b &&
+ cp initial a &&
+ echo b >>b &&
+ echo a >>a &&
+ git add b a &&
+ test_tick && git commit -m initial &&
+
+ git branch L &&
+ git branch R &&
+
+ # Handle the left side
+ git checkout L &&
+ mv -f b_L1 b &&
+ mv -f a_L1 a &&
+ git add b a &&
+ test_tick && git commit -m "version L1 of files" &&
+ git tag L1 &&
+
+ # Handle the right side
+ git checkout R &&
+ mv -f b_R1 b &&
+ mv -f a_R1 a &&
+ git add b a &&
+ test_tick && git commit -m "version R1 of files" &&
+ git tag R1 &&
+
+ # Create first merge on left side
+ git checkout L &&
+ test_must_fail git merge R1 &&
+ mv -f b_L2 b &&
+ mv -f a_L2 a &&
+ git add b a &&
+ git mv b m &&
+ test_tick && git commit -m "left merge, rename b->m" &&
+ git tag L2 &&
+
+ # Create first merge on right side
+ git checkout R &&
+ test_must_fail git merge L1 &&
+ mv -f b_R2 b &&
+ mv -f a_R2 a &&
+ git add b a &&
+ git mv a m &&
+ test_tick && git commit -m "right merge, rename a->m" &&
+ git tag R2
+ )
+'
+
+test_expect_success 'check nested conflicts' '
+ (
+ cd nested_conflicts &&
+
+ git clean -f &&
+ MAIN=$(git rev-parse --short main) &&
+ git checkout L2^0 &&
+
+ # Merge must fail; there is a conflict
+ test_must_fail git -c merge.conflictstyle=diff3 merge -s recursive R2^0 &&
+
+ # Make sure the index has the right number of entries
+ git ls-files -s >out &&
+ test_line_count = 2 out &&
+ git ls-files -u >out &&
+ test_line_count = 2 out &&
+ # Ensure we have the correct number of untracked files
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ # Create a and b from virtual merge base X
+ git cat-file -p main:a >base &&
+ git cat-file -p L1:a >ours &&
+ git cat-file -p R1:a >theirs &&
+ test_must_fail git merge-file --diff3 \
+ -L "Temporary merge branch 1" \
+ -L "$MAIN" \
+ -L "Temporary merge branch 2" \
+ ours \
+ base \
+ theirs &&
+ sed -e "s/^\([<|=>]\)/\1\1/" ours >vmb_a &&
+
+ git cat-file -p main:b >base &&
+ git cat-file -p L1:b >ours &&
+ git cat-file -p R1:b >theirs &&
+ test_must_fail git merge-file --diff3 \
+ -L "Temporary merge branch 1" \
+ -L "$MAIN" \
+ -L "Temporary merge branch 2" \
+ ours \
+ base \
+ theirs &&
+ sed -e "s/^\([<|=>]\)/\1\1/" ours >vmb_b &&
+
+ # Compare :2:m to expected values
+ git cat-file -p L2:m >ours &&
+ git cat-file -p R2:b >theirs &&
+ test_must_fail git merge-file --diff3 \
+ -L "HEAD:m" \
+ -L "merged common ancestors:b" \
+ -L "R2^0:b" \
+ ours \
+ vmb_b \
+ theirs &&
+ sed -e "s/^\([<|=>]\)/\1\1/" ours >m_stage_2 &&
+ git cat-file -p :2:m >actual &&
+ test_cmp m_stage_2 actual &&
+
+ # Compare :3:m to expected values
+ git cat-file -p L2:a >ours &&
+ git cat-file -p R2:m >theirs &&
+ test_must_fail git merge-file --diff3 \
+ -L "HEAD:a" \
+ -L "merged common ancestors:a" \
+ -L "R2^0:m" \
+ ours \
+ vmb_a \
+ theirs &&
+ sed -e "s/^\([<|=>]\)/\1\1/" ours >m_stage_3 &&
+ git cat-file -p :3:m >actual &&
+ test_cmp m_stage_3 actual &&
+
+ # Compare m to expected contents
+ >empty &&
+ cp m_stage_2 expected_final_m &&
+ test_must_fail git merge-file --diff3 \
+ -L "HEAD" \
+ -L "merged common ancestors" \
+ -L "R2^0" \
+ expected_final_m \
+ empty \
+ m_stage_3 &&
+ test_cmp expected_final_m m
+ )
+'
+
+# Setup:
+# L1---L2---L3
+# / \ / \ / \
+# main X1 X2 ?
+# \ / \ / \ /
+# R1---R2---R3
+#
+# Where:
+# main has one file named 'content'
+# branches L1 and R1 both modify each of the two files in conflicting ways
+#
+# L<n> (n>1) is a merge of R<n-1> into L<n-1>
+# R<n> (n>1) is a merge of L<n-1> into R<n-1>
+# L<n> and R<n> resolve the conflicts differently.
+#
+# X<n> is an auto-generated merge-base used when merging L<n+1> and R<n+1>.
+# By construction, X1 has conflict markers due to conflicting versions.
+# X2, due to using merge.conflictstyle=3, has nested conflict markers.
+#
+# So, merging R3 into L3 using merge.conflictstyle=3 should show the
+# nested conflict markers from X2 in the base version -- that means we
+# have three levels of conflict markers. Can we distinguish all three?
+
+test_expect_success 'setup virtual merge base with nested conflicts' '
+ git init virtual_merge_base_has_nested_conflicts &&
+ (
+ cd virtual_merge_base_has_nested_conflicts &&
+
+ # Create some related files now
+ printf "Random base content line %d\n" $(test_seq 1 10) >content &&
+
+ # Setup original commit
+ git add content &&
+ test_tick && git commit -m initial &&
+
+ git branch L &&
+ git branch R &&
+
+ # Create L1
+ git checkout L &&
+ echo left >>content &&
+ git add content &&
+ test_tick && git commit -m "version L1 of content" &&
+ git tag L1 &&
+
+ # Create R1
+ git checkout R &&
+ echo right >>content &&
+ git add content &&
+ test_tick && git commit -m "version R1 of content" &&
+ git tag R1 &&
+
+ # Create L2
+ git checkout L &&
+ test_must_fail git -c merge.conflictstyle=diff3 merge R1 &&
+ git checkout L1 content &&
+ test_tick && git commit -m "version L2 of content" &&
+ git tag L2 &&
+
+ # Create R2
+ git checkout R &&
+ test_must_fail git -c merge.conflictstyle=diff3 merge L1 &&
+ git checkout R1 content &&
+ test_tick && git commit -m "version R2 of content" &&
+ git tag R2 &&
+
+ # Create L3
+ git checkout L &&
+ test_must_fail git -c merge.conflictstyle=diff3 merge R2 &&
+ git checkout L1 content &&
+ test_tick && git commit -m "version L3 of content" &&
+ git tag L3 &&
+
+ # Create R3
+ git checkout R &&
+ test_must_fail git -c merge.conflictstyle=diff3 merge L2 &&
+ git checkout R1 content &&
+ test_tick && git commit -m "version R3 of content" &&
+ git tag R3
+ )
+'
+
+test_expect_success 'check virtual merge base with nested conflicts' '
+ (
+ cd virtual_merge_base_has_nested_conflicts &&
+
+ MAIN=$(git rev-parse --short main) &&
+ git checkout L3^0 &&
+
+ # Merge must fail; there is a conflict
+ test_must_fail git -c merge.conflictstyle=diff3 merge -s recursive R3^0 &&
+
+ # Make sure the index has the right number of entries
+ git ls-files -s >out &&
+ test_line_count = 3 out &&
+ git ls-files -u >out &&
+ test_line_count = 3 out &&
+ # Ensure we have the correct number of untracked files
+ git ls-files -o >out &&
+ test_line_count = 1 out &&
+
+ # Compare :[23]:content to expected values
+ git rev-parse L1:content R1:content >expect &&
+ git rev-parse :2:content :3:content >actual &&
+ test_cmp expect actual &&
+
+ # Imitate X1 merge base, except without long enough conflict
+ # markers because a subsequent sed will modify them. Put
+ # result into vmb.
+ git cat-file -p main:content >base &&
+ git cat-file -p L:content >left &&
+ git cat-file -p R:content >right &&
+ cp left merged-once &&
+ test_must_fail git merge-file --diff3 \
+ -L "Temporary merge branch 1" \
+ -L "$MAIN" \
+ -L "Temporary merge branch 2" \
+ merged-once \
+ base \
+ right &&
+ sed -e "s/^\([<|=>]\)/\1\1\1/" merged-once >vmb &&
+
+ # Imitate X2 merge base, overwriting vmb. Note that we
+ # extend both sets of conflict markers to make them longer
+ # with the sed command.
+ cp left merged-twice &&
+ test_must_fail git merge-file --diff3 \
+ -L "Temporary merge branch 1" \
+ -L "merged common ancestors" \
+ -L "Temporary merge branch 2" \
+ merged-twice \
+ vmb \
+ right &&
+ sed -e "s/^\([<|=>]\)/\1\1\1/" merged-twice >vmb &&
+
+ # Compare :1:content to expected value
+ git cat-file -p :1:content >actual &&
+ test_cmp vmb actual &&
+
+ # Determine expected content in final outer merge, compare to
+ # what the merge generated.
+ cp -f left expect &&
+ test_must_fail git merge-file --diff3 \
+ -L "HEAD" -L "merged common ancestors" -L "R3^0" \
+ expect vmb right &&
+ test_cmp expect content
+ )
+'
+
+test_done