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| -rwxr-xr-x | t/t6043-merge-rename-directories.sh | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/t/t6043-merge-rename-directories.sh b/t/t6043-merge-rename-directories.sh index 6db1439675..e211e8ca31 100755 --- a/t/t6043-merge-rename-directories.sh +++ b/t/t6043-merge-rename-directories.sh @@ -1912,4 +1912,408 @@ test_expect_failure '7e-check: transitive rename in rename/delete AND dirs in th ) ' +########################################################################### +# SECTION 8: Suboptimal merges +# +# As alluded to in the last section, the ruleset we have built up for +# detecting directory renames unfortunately has some special cases where it +# results in slightly suboptimal or non-intuitive behavior. This section +# explores these cases. +# +# To be fair, we already had non-intuitive or suboptimal behavior for most +# of these cases in git before introducing implicit directory rename +# detection, but it'd be nice if there was a modified ruleset out there +# that handled these cases a bit better. +########################################################################### + +# Testcase 8a, Dual-directory rename, one into the others' way +# Commit O. x/{a,b}, y/{c,d} +# Commit A. x/{a,b,e}, y/{c,d,f} +# Commit B. y/{a,b}, z/{c,d} +# +# Possible Resolutions: +# w/o dir-rename detection: y/{a,b,f}, z/{c,d}, x/e +# Currently expected: y/{a,b,e,f}, z/{c,d} +# Optimal: y/{a,b,e}, z/{c,d,f} +# +# Note: Both x and y got renamed and it'd be nice to detect both, and we do +# better with directory rename detection than git did without, but the +# simple rule from section 5 prevents me from handling this as optimally as +# we potentially could. + +test_expect_success '8a-setup: Dual-directory rename, one into the others way' ' + test_create_repo 8a && + ( + cd 8a && + + mkdir x && + mkdir y && + echo a >x/a && + echo b >x/b && + echo c >y/c && + echo d >y/d && + git add x y && + test_tick && + git commit -m "O" && + + git branch O && + git branch A && + git branch B && + + git checkout A && + echo e >x/e && + echo f >y/f && + git add x/e y/f && + test_tick && + git commit -m "A" && + + git checkout B && + git mv y z && + git mv x y && + test_tick && + git commit -m "B" + ) +' + +test_expect_failure '8a-check: Dual-directory rename, one into the others way' ' + ( + cd 8a && + + git checkout A^0 && + + git merge -s recursive B^0 && + + git ls-files -s >out && + test_line_count = 6 out && + git ls-files -u >out && + test_line_count = 0 out && + git ls-files -o >out && + test_line_count = 1 out && + + git rev-parse >actual \ + HEAD:y/a HEAD:y/b HEAD:y/e HEAD:y/f HEAD:z/c HEAD:z/d && + git rev-parse >expect \ + O:x/a O:x/b A:x/e A:y/f O:y/c O:y/d && + test_cmp expect actual + ) +' + +# Testcase 8b, Dual-directory rename, one into the others' way, with conflicting filenames +# Commit O. x/{a_1,b_1}, y/{a_2,b_2} +# Commit A. x/{a_1,b_1,e_1}, y/{a_2,b_2,e_2} +# Commit B. y/{a_1,b_1}, z/{a_2,b_2} +# +# w/o dir-rename detection: y/{a_1,b_1,e_2}, z/{a_2,b_2}, x/e_1 +# Currently expected: <same> +# Scary: y/{a_1,b_1}, z/{a_2,b_2}, CONFLICT(add/add, e_1 vs. e_2) +# Optimal: y/{a_1,b_1,e_1}, z/{a_2,b_2,e_2} +# +# Note: Very similar to 8a, except instead of 'e' and 'f' in directories x and +# y, both are named 'e'. Without directory rename detection, neither file +# moves directories. Implement directory rename detection suboptimally, and +# you get an add/add conflict, but both files were added in commit A, so this +# is an add/add conflict where one side of history added both files -- +# something we can't represent in the index. Obviously, we'd prefer the last +# resolution, but our previous rules are too coarse to allow it. Using both +# the rules from section 4 and section 5 save us from the Scary resolution, +# making us fall back to pre-directory-rename-detection behavior for both +# e_1 and e_2. + +test_expect_success '8b-setup: Dual-directory rename, one into the others way, with conflicting filenames' ' + test_create_repo 8b && + ( + cd 8b && + + mkdir x && + mkdir y && + echo a1 >x/a && + echo b1 >x/b && + echo a2 >y/a && + echo b2 >y/b && + git add x y && + test_tick && + git commit -m "O" && + + git branch O && + git branch A && + git branch B && + + git checkout A && + echo e1 >x/e && + echo e2 >y/e && + git add x/e y/e && + test_tick && + git commit -m "A" && + + git checkout B && + git mv y z && + git mv x y && + test_tick && + git commit -m "B" + ) +' + +test_expect_success '8b-check: Dual-directory rename, one into the others way, with conflicting filenames' ' + ( + cd 8b && + + git checkout A^0 && + + git merge -s recursive B^0 && + + git ls-files -s >out && + test_line_count = 6 out && + git ls-files -u >out && + test_line_count = 0 out && + git ls-files -o >out && + test_line_count = 1 out && + + git rev-parse >actual \ + HEAD:y/a HEAD:y/b HEAD:z/a HEAD:z/b HEAD:x/e HEAD:y/e && + git rev-parse >expect \ + O:x/a O:x/b O:y/a O:y/b A:x/e A:y/e && + test_cmp expect actual + ) +' + +# Testcase 8c, rename+modify/delete +# (Related to testcases 5b and 8d) +# Commit O: z/{b,c,d} +# Commit A: y/{b,c} +# Commit B: z/{b,c,d_modified,e} +# Expected: y/{b,c,e}, CONFLICT(rename+modify/delete: x/d -> y/d or deleted) +# +# Note: This testcase doesn't present any concerns for me...until you +# compare it with testcases 5b and 8d. See notes in 8d for more +# details. + +test_expect_success '8c-setup: rename+modify/delete' ' + test_create_repo 8c && + ( + cd 8c && + + mkdir z && + echo b >z/b && + echo c >z/c && + test_seq 1 10 >z/d && + git add z && + test_tick && + git commit -m "O" && + + git branch O && + git branch A && + git branch B && + + git checkout A && + git rm z/d && + git mv z y && + test_tick && + git commit -m "A" && + + git checkout B && + echo 11 >z/d && + test_chmod +x z/d && + echo e >z/e && + git add z/d z/e && + test_tick && + git commit -m "B" + ) +' + +test_expect_failure '8c-check: rename+modify/delete' ' + ( + cd 8c && + + git checkout A^0 && + + test_must_fail git merge -s recursive B^0 >out && + test_i18ngrep "CONFLICT (rename/delete).* z/d.*y/d" out && + + git ls-files -s >out && + test_line_count = 4 out && + git ls-files -u >out && + test_line_count = 1 out && + git ls-files -o >out && + test_line_count = 1 out && + + git rev-parse >actual \ + :0:y/b :0:y/c :0:y/e :3:y/d && + git rev-parse >expect \ + O:z/b O:z/c B:z/e B:z/d && + test_cmp expect actual && + + test_must_fail git rev-parse :1:y/d && + test_must_fail git rev-parse :2:y/d && + git ls-files -s y/d | grep ^100755 && + test_path_is_file y/d + ) +' + +# Testcase 8d, rename/delete...or not? +# (Related to testcase 5b; these may appear slightly inconsistent to users; +# Also related to testcases 7d and 7e) +# Commit O: z/{b,c,d} +# Commit A: y/{b,c} +# Commit B: z/{b,c,d,e} +# Expected: y/{b,c,e} +# +# Note: It would also be somewhat reasonable to resolve this as +# y/{b,c,e}, CONFLICT(rename/delete: x/d -> y/d or deleted) +# The logic being that the only difference between this testcase and 8c +# is that there is no modification to d. That suggests that instead of a +# rename/modify vs. delete conflict, we should just have a rename/delete +# conflict, otherwise we are being inconsistent. +# +# However...as far as consistency goes, we didn't report a conflict for +# path d_1 in testcase 5b due to a different file being in the way. So, +# we seem to be forced to have cases where users can change things +# slightly and get what they may perceive as inconsistent results. It +# would be nice to avoid that, but I'm not sure I see how. +# +# In this case, I'm leaning towards: commit A was the one that deleted z/d +# and it did the rename of z to y, so the two "conflicts" (rename vs. +# delete) are both coming from commit A, which is illogical. Conflicts +# during merging are supposed to be about opposite sides doing things +# differently. + +test_expect_success '8d-setup: rename/delete...or not?' ' + test_create_repo 8d && + ( + cd 8d && + + mkdir z && + echo b >z/b && + echo c >z/c && + test_seq 1 10 >z/d && + git add z && + test_tick && + git commit -m "O" && + + git branch O && + git branch A && + git branch B && + + git checkout A && + git rm z/d && + git mv z y && + test_tick && + git commit -m "A" && + + git checkout B && + echo e >z/e && + git add z/e && + test_tick && + git commit -m "B" + ) +' + +test_expect_failure '8d-check: rename/delete...or not?' ' + ( + cd 8d && + + git checkout A^0 && + + git merge -s recursive B^0 && + + git ls-files -s >out && + test_line_count = 3 out && + + git rev-parse >actual \ + HEAD:y/b HEAD:y/c HEAD:y/e && + git rev-parse >expect \ + O:z/b O:z/c B:z/e && + test_cmp expect actual + ) +' + +# Testcase 8e, Both sides rename, one side adds to original directory +# Commit O: z/{b,c} +# Commit A: y/{b,c} +# Commit B: w/{b,c}, z/d +# +# Possible Resolutions: +# w/o dir-rename detection: z/d, CONFLICT(z/b -> y/b vs. w/b), +# CONFLICT(z/c -> y/c vs. w/c) +# Currently expected: y/d, CONFLICT(z/b -> y/b vs. w/b), +# CONFLICT(z/c -> y/c vs. w/c) +# Optimal: ?? +# +# Notes: In commit A, directory z got renamed to y. In commit B, directory z +# did NOT get renamed; the directory is still present; instead it is +# considered to have just renamed a subset of paths in directory z +# elsewhere. Therefore, the directory rename done in commit A to z/ +# applies to z/d and maps it to y/d. +# +# It's possible that users would get confused about this, but what +# should we do instead? Silently leaving at z/d seems just as bad or +# maybe even worse. Perhaps we could print a big warning about z/d +# and how we're moving to y/d in this case, but when I started thinking +# about the ramifications of doing that, I didn't know how to rule out +# that opening other weird edge and corner cases so I just punted. + +test_expect_success '8e-setup: Both sides rename, one side adds to original directory' ' + test_create_repo 8e && + ( + cd 8e && + + mkdir z && + echo b >z/b && + echo c >z/c && + git add z && + test_tick && + git commit -m "O" && + + git branch O && + git branch A && + git branch B && + + git checkout A && + git mv z y && + test_tick && + git commit -m "A" && + + git checkout B && + git mv z w && + mkdir z && + echo d >z/d && + git add z/d && + test_tick && + git commit -m "B" + ) +' + +test_expect_failure '8e-check: Both sides rename, one side adds to original directory' ' + ( + cd 8e && + + git checkout A^0 && + + test_must_fail git merge -s recursive B^0 >out 2>err && + test_i18ngrep CONFLICT.*rename/rename.*z/c.*y/c.*w/c out && + test_i18ngrep CONFLICT.*rename/rename.*z/b.*y/b.*w/b out && + + git ls-files -s >out && + test_line_count = 7 out && + git ls-files -u >out && + test_line_count = 6 out && + git ls-files -o >out && + test_line_count = 2 out && + + git rev-parse >actual \ + :1:z/b :2:y/b :3:w/b :1:z/c :2:y/c :3:w/c :0:y/d && + git rev-parse >expect \ + O:z/b O:z/b O:z/b O:z/c O:z/c O:z/c B:z/d && + test_cmp expect actual && + + git hash-object >actual \ + y/b w/b y/c w/c && + git rev-parse >expect \ + O:z/b O:z/b O:z/c O:z/c && + test_cmp expect actual && + + test_path_is_missing z/b && + test_path_is_missing z/c + ) +' + test_done |