> Ben: Could you rerun all your special testcases to make sure things > are good with this patch too? It'd be much appreciated. Many thanks for the super fast turnaround Elijah and Szeder! I can confirm with 2.22.0-rc3 plus your patch this failing testcase now passes, and indeed our entire Git test suite passes. Best Regards, Ben Humphreys On Tue, Jun 4, 2019 at 5:26 PM Elijah Newren <newren@xxxxxxxxx> wrote: > > On Mon, Jun 3, 2019 at 7:30 PM SZEDER Gábor <szeder.dev@xxxxxxxxx> wrote: > > > > On Tue, Jun 04, 2019 at 11:32:24AM +1000, Ben Humphreys wrote: > > > Hi folks, > > > > > > I’m one of the Bitbucket Server developers and I just wanted to let > > > you know of one of our test cases that is now failing on the 2.22.0 > > > release candidates (tested rc2 and rc3). I’m still looking into it, > > > but figure the release is probably imminent so worth reporting sooner > > > than later. > > > > > > The problem seems to be related to some recent changes in > > > merge-recursive.c. I’ve made available our test dataset and the > > > following steps will reproduce the problem: > > > > > > $ git --version > > > git version 2.22.0.rc3 > > > > > > $ git clone https://bitbucket.org/ben_humphreys/merge-dataset.git > > > $ cd merge-dataset > > > $ git checkout branch_that_has_rename_add_triggering_content_conflict_trgt > > > $ git merge origin/branch_that_has_rename_add_triggering_content_conflict_src > > > Assertion failed: (a->path && b->path), function merge_3way, file > > > merge-recursive.c, line 1044. > > > Abort trap: 6 > > > > > > The assertion is failing because b->path is null: > > > > > > (lldb) print a->path > > > (char *const) $2 = 0x00007f8e177025f8 "count.txt" > > > (lldb) print b->path > > > (char *const) $3 = 0x0000000000000000 <no value available> > > > > merge_3way() is called from merge_mode_and_contents(), which in turn > > is called from handle_rename_add(), which was modified in 8daec1df03 > > (merge-recursive: switch from (oid,mode) pairs to a diff_filespec, > > 2019-04-05) like this: > > > > > diff --git a/merge-recursive.c b/merge-recursive.c > > > index ada1c19ed2..1d2c9e1772 100644 > > > --- a/merge-recursive.c > > > +++ b/merge-recursive.c > > > > > > @@ -1654,7 +1625,6 @@ static int handle_rename_add(struct merge_options *opt, > > > /* a was renamed to c, and a separate c was added. */ > > > struct diff_filespec *a = ci->ren1->pair->one; > > > struct diff_filespec *c = ci->ren1->pair->two; > > > - struct diff_filespec tmp; > > > char *path = c->path; > > > char *prev_path_desc; > > > struct merge_file_info mfi; > > > @@ -1669,23 +1639,21 @@ static int handle_rename_add(struct merge_options *opt, > > > a->path, c->path, rename_branch, > > > c->path, add_branch); > > > > > > - filespec_from_entry(&tmp, ci->ren1->src_entry, other_stage); > > > - tmp.path = a->path; > > > > Note that 'tmp.path' used to be set ... > > > > > - > > > prev_path_desc = xstrfmt("version of %s from %s", path, a->path); > > > - if (merge_mode_and_contents(opt, a, c, &tmp, > > > > ... and that this 'tmp' used to become 'b' in > > merge_mode_and_contents() and then in merge_3way(). > > > > > + if (merge_mode_and_contents(opt, a, c, > > > + &ci->ren1->src_entry->stages[other_stage], > > > prev_path_desc, > > > opt->branch1, opt->branch2, > > > 1 + opt->call_depth * 2, &mfi)) > > > return -1; > > > free(prev_path_desc); > > > > > > This one-liner patch below the issue, the merge fails with conflicts > > as expected, but, honestly, I have no idea what I am doing :) At > > least the test suite still passes, but that might not mean all that > > much since it missed this issue in the first place... > > > > diff --git a/merge-recursive.c b/merge-recursive.c > > index a7bcfcbeb4..d2e380b7ed 100644 > > --- a/merge-recursive.c > > +++ b/merge-recursive.c > > @@ -1660,6 +1660,7 @@ static int handle_rename_add(struct merge_options *opt, > > c->path, add_branch); > > > > prev_path_desc = xstrfmt("version of %s from %s", path, a->path); > > + ci->ren1->src_entry->stages[other_stage].path = a->path; > > if (merge_mode_and_contents(opt, a, c, > > &ci->ren1->src_entry->stages[other_stage], > > prev_path_desc, > > > > > > This analysis and patch are correct; I somehow deleted the setting of the > path here in what should have been a straightforward conversion. > > I've tried to look through every other callsite to merge_3way to see > if any others fail to set the paths; there's a dozen or two of them. > I think this was the only one that was missed, but honestly I'm > exhausted right now and not sure I'm thinking straight. So I'll > recheck tomorrow and do a bunch more testing. > > Of course, this wasn't the only bug; it also showed we had a glaring > whole in our test coverage -- there's a dearth of tests for rename/add > conflicts, and in particular none involving content merges for the > rename side. So, I created a patch which adds some tests for that > (which triggered the assertion error). I pulled SZEDER's fix into the > same patch and added a commit message explaining the issue, using a > Based-on-patch-by tag for the fix. SZEDER: if you'd like to see this > in a different format (maybe I add tests which show the error and then > in a separate patch authored by you we introduce your fix?), just let > me know. > > Since we're at -rc3 already, even if it is a trivial patch, I'm going to > try to re-analyze it all tomorrow to make sure I didn't miss anything and > see if I can find more tests to throw at it. > > Ben: Could you rerun all your special testcases to make sure things > are good with this patch too? It'd be much appreciated. > > Thanks Ben for reporting and SZEDER for jumping on and analyzing and > cc'ing me. > > Sorry for the headache folks, > Elijah > > > -- 8< -- > Subject: [PATCH] merge-recursive: restore accidentally dropped setting of path > > In commit 8daec1df03de ("merge-recursive: switch from (oid,mode) pairs > to a diff_filespec", 2019-04-05), we actually switched from > (oid,mode,path) triplets to a diff_filespec -- but most callsites in the > patch only needed to worry about oid and mode so the commit message > focused on that. The oversight in the commit message apparently spilled > over to the code as will; one of the dozen or so callsites accidentally > dropped the setting of the path in the conversion. Restore the path > setting in that location. > > Also, this pointed out that our testsuite was lacking a good rename/add > test, at least one that involved the need for merge content with the > rename. Add such a test, and since rename/add vs. add/rename could > possibly be important, redo the merge the opposite direction to make > sure we don't have issues with the direction of the merge. These > testcases failed before restoring the setting of path, but with the > paths appropriately set the testcases both pass. > > Reported-by: Ben Humphreys <behumphreys@xxxxxxxxxxxxx> > Based-on-patch-by: SZEDER Gábor <szeder.dev@xxxxxxxxx> > Signed-off-by: Elijah Newren <newren@xxxxxxxxx> > --- > merge-recursive.c | 1 + > t/t6042-merge-rename-corner-cases.sh | 118 +++++++++++++++++++++++++++ > 2 files changed, 119 insertions(+) > > diff --git a/merge-recursive.c b/merge-recursive.c > index a7bcfcbeb4..d2e380b7ed 100644 > --- a/merge-recursive.c > +++ b/merge-recursive.c > @@ -1660,6 +1660,7 @@ static int handle_rename_add(struct merge_options *opt, > c->path, add_branch); > > prev_path_desc = xstrfmt("version of %s from %s", path, a->path); > + ci->ren1->src_entry->stages[other_stage].path = a->path; > if (merge_mode_and_contents(opt, a, c, > &ci->ren1->src_entry->stages[other_stage], > prev_path_desc, > diff --git a/t/t6042-merge-rename-corner-cases.sh b/t/t6042-merge-rename-corner-cases.sh > index 09dfa8bd92..0793f64099 100755 > --- a/t/t6042-merge-rename-corner-cases.sh > +++ b/t/t6042-merge-rename-corner-cases.sh > @@ -411,6 +411,124 @@ test_expect_success 'disappearing dir in rename/directory conflict handled' ' > ) > ' > > +# Test for basic rename/add-dest conflict, with rename needing content merge: > +# Commit O: a > +# Commit A: rename a->b, modifying b too > +# Commit B: modify a, add different b > + > +test_expect_success 'setup rename-with-content-merge vs. add' ' > + test_create_repo rename-with-content-merge-and-add && > + ( > + cd rename-with-content-merge-and-add && > + > + test_seq 1 5 >a && > + git add a && > + git commit -m O && > + git tag O && > + > + git checkout -b A O && > + git mv a b && > + test_seq 0 5 >b && > + git add b && > + git commit -m A && > + > + git checkout -b B O && > + echo 6 >>a && > + echo hello world >b && > + git add a b && > + git commit -m B > + ) > +' > + > +test_expect_success 'handle rename-with-content-merge vs. add' ' > + ( > + cd rename-with-content-merge-and-add && > + > + git checkout A^0 && > + > + test_must_fail git merge -s recursive B^0 >out && > + test_i18ngrep "CONFLICT (rename/add)" out && > + > + git ls-files -s >out && > + test_line_count = 2 out && > + git ls-files -u >out && > + test_line_count = 2 out && > + git ls-files -u b >out && > + test_line_count = 2 out && > + git ls-files -o >out && > + test_line_count = 1 out && > + > + test_path_is_missing a && > + test_path_is_file b && > + > + test_seq 0 6 >tmp && > + git hash-object tmp >expect && > + git rev-parse B:b >>expect && > + git rev-parse >actual \ > + :2:b :3:b && > + test_cmp expect actual && > + > + # Test that the two-way merge in b is as expected > + git cat-file -p :2:b >>ours && > + git cat-file -p :3:b >>theirs && > + >empty && > + test_must_fail git merge-file \ > + -L "HEAD" \ > + -L "" \ > + -L "B^0" \ > + ours empty theirs && > + git hash-object b >actual && > + git hash-object ours >expect && > + test_cmp expect actual > + ) > +' > + > +test_expect_success 'handle rename-with-content-merge vs. add, merge other way' ' > + ( > + cd rename-with-content-merge-and-add && > + > + git reset --hard && > + git clean -fdx && > + > + git checkout B^0 && > + > + test_must_fail git merge -s recursive A^0 >out && > + test_i18ngrep "CONFLICT (rename/add)" out && > + > + git ls-files -s >out && > + test_line_count = 2 out && > + git ls-files -u >out && > + test_line_count = 2 out && > + git ls-files -u b >out && > + test_line_count = 2 out && > + git ls-files -o >out && > + test_line_count = 1 out && > + > + test_path_is_missing a && > + test_path_is_file b && > + > + test_seq 0 6 >tmp && > + git rev-parse B:b >expect && > + git hash-object tmp >>expect && > + git rev-parse >actual \ > + :2:b :3:b && > + test_cmp expect actual && > + > + # Test that the two-way merge in b is as expected > + git cat-file -p :2:b >>ours && > + git cat-file -p :3:b >>theirs && > + >empty && > + test_must_fail git merge-file \ > + -L "HEAD" \ > + -L "" \ > + -L "A^0" \ > + ours empty theirs && > + git hash-object b >actual && > + git hash-object ours >expect && > + test_cmp expect actual > + ) > +' > + > # Test for all kinds of things that can go wrong with rename/rename (2to1): > # Commit A: new files: a & b > # Commit B: rename a->c, modify b > -- > 2.22.0.rc3.1.g617c1f72bf >
