#!/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' ' test_create_repo basic-rename && ( cd basic-rename && 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' ' ( 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' ' test_create_repo rename-modify && ( cd rename-modify && 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 && 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' ' test_create_repo 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' ' test_create_repo 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' ' test_create_repo 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' ' test_create_repo 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' ' test_create_repo 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' ' test_create_repo 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' ' test_create_repo 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' ' test_create_repo 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' ' test_create_repo submodule-modify-modify && ( cd submodule-modify-modify && test_create_repo 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' ' test_create_repo submodule-add-add && ( cd submodule-add-add && test_create_repo 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)' ' test_create_repo submodule-symlink-add-add && ( cd submodule-symlink-add-add && test_create_repo 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' ' test_create_repo 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' ' test_create_repo nested_conflicts && ( cd nested_conflicts && # Create some related files now for i in $(test_seq 1 10) do echo Random base content line $i done >initial && cp initial b_L1 && cp initial b_R1 && cp initial b_L2 && cp initial b_R2 && cp initial a_L1 && cp initial a_R1 && cp initial a_L2 && cp initial a_R2 && test_write_lines b b_L1 >>b_L1 && test_write_lines b b_R1 >>b_R1 && test_write_lines b b_L2 >>b_L2 && test_write_lines b b_R2 >>b_R2 && test_write_lines a a_L1 >>a_L1 && test_write_lines a a_R1 >>a_R1 && test_write_lines a a_L2 >>a_L2 && test_write_lines a a_R2 >>a_R2 && # Setup original commit (or merge-base), consisting of # files named "b" and "a" cp initial b && cp initial a && echo b >>b && echo a >>a && git add b a && test_tick && git commit -m initial && git branch L && git branch R && # Handle the left side git checkout L && mv -f b_L1 b && mv -f a_L1 a && git add b a && test_tick && git commit -m "version L1 of files" && git tag L1 && # Handle the right side git checkout R && mv -f b_R1 b && mv -f a_R1 a && git add b a && test_tick && git commit -m "version R1 of files" && git tag R1 && # Create first merge on left side git checkout L && test_must_fail git merge R1 && mv -f b_L2 b && mv -f a_L2 a && git add b a && git mv b m && test_tick && git commit -m "left merge, rename b->m" && git tag L2 && # Create first merge on right side git checkout R && test_must_fail git merge L1 && mv -f b_R2 b && mv -f a_R2 a && git add b a && git mv a m && test_tick && git commit -m "right merge, rename a->m" && git tag R2 ) ' test_expect_success 'check nested conflicts' ' ( cd nested_conflicts && git clean -f && MAIN=$(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' ' test_create_repo virtual_merge_base_has_nested_conflicts && ( cd virtual_merge_base_has_nested_conflicts && # Create some related files now for i in $(test_seq 1 10) do echo Random base content line $i done >content && # Setup original commit git add content && test_tick && git commit -m initial && git branch L && git branch R && # Create L1 git checkout L && echo left >>content && git add content && test_tick && git commit -m "version L1 of content" && git tag L1 && # Create R1 git checkout R && echo right >>content && git add content && test_tick && git commit -m "version R1 of content" && git tag R1 && # Create L2 git checkout L && test_must_fail git -c merge.conflictstyle=diff3 merge R1 && git checkout L1 content && test_tick && git commit -m "version L2 of content" && git tag L2 && # Create R2 git checkout R && test_must_fail git -c merge.conflictstyle=diff3 merge L1 && git checkout R1 content && test_tick && git commit -m "version R2 of content" && git tag R2 && # Create L3 git checkout L && test_must_fail git -c merge.conflictstyle=diff3 merge R2 && git checkout L1 content && test_tick && git commit -m "version L3 of content" && git tag L3 && # Create R3 git checkout R && test_must_fail git -c merge.conflictstyle=diff3 merge L2 && git checkout R1 content && test_tick && git commit -m "version R3 of content" && git tag R3 ) ' test_expect_success 'check virtual merge base with nested conflicts' ' ( cd virtual_merge_base_has_nested_conflicts && MAIN=$(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