From 49b8133a9ece199a17db8bb2545202c6eac67485 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Tue, 22 Oct 2019 21:22:50 +0000 Subject: [PATCH] merge-recursive: fix merging a subdirectory into the root directory We allow renaming all entries in e.g. a directory named z/ into a directory named y/ to be detected as a z/ -> y/ rename, so that if the other side of history adds any files to the directory z/ in the mean time, we can provide the hint that they should be moved to y/. There is no reason to not allow 'y/' to be the root directory, but the code did not handle that case correctly. Add a testcase and the necessary special checks to support this case. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- merge-recursive.c | 52 ++++++++++++- t/t6043-merge-rename-directories.sh | 114 ++++++++++++++++++++++++++++ 2 files changed, 163 insertions(+), 3 deletions(-) diff --git a/merge-recursive.c b/merge-recursive.c index f80e48f623..ec60715368 100644 --- a/merge-recursive.c +++ b/merge-recursive.c @@ -1931,6 +1931,16 @@ static char *apply_dir_rename(struct dir_rename_entry *entry, return NULL; oldlen = strlen(entry->dir); + if (entry->new_dir.len == 0) + /* + * If someone renamed/merged a subdirectory into the root + * directory (e.g. 'some/subdir' -> ''), then we want to + * avoid returning + * '' + '/filename' + * as the rename; we need to make old_path + oldlen advance + * past the '/' character. + */ + oldlen++; newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1; strbuf_grow(&new_path, newlen); strbuf_addbuf(&new_path, &entry->new_dir); @@ -1963,8 +1973,26 @@ static void get_renamed_dir_portion(const char *old_path, const char *new_path, */ end_of_old = strrchr(old_path, '/'); end_of_new = strrchr(new_path, '/'); - if (end_of_old == NULL || end_of_new == NULL) - return; /* We haven't modified *old_dir or *new_dir yet. */ + + /* + * If end_of_old is NULL, old_path wasn't in a directory, so there + * could not be a directory rename (our rule elsewhere that a + * directory which still exists is not considered to have been + * renamed means the root directory can never be renamed -- because + * the root directory always exists). + */ + if (end_of_old == NULL) + return; /* Note: *old_dir and *new_dir are still NULL */ + + /* + * If new_path contains no directory (end_of_new is NULL), then we + * have a rename of old_path's directory to the root directory. + */ + if (end_of_new == NULL) { + *old_dir = xstrndup(old_path, end_of_old - old_path); + *new_dir = xstrdup(""); + return; + } /* Find the first non-matching character traversing backwards */ while (*--end_of_new == *--end_of_old && @@ -1978,7 +2006,25 @@ static void get_renamed_dir_portion(const char *old_path, const char *new_path, */ if (end_of_old == old_path && end_of_new == new_path && *end_of_old == *end_of_new) - return; /* We haven't modified *old_dir or *new_dir yet. */ + return; /* Note: *old_dir and *new_dir are still NULL */ + + /* + * If end_of_new got back to the beginning of its string, and + * end_of_old got back to the beginning of some subdirectory, then + * we have a rename/merge of a subdirectory into the root, which + * needs slightly special handling. + * + * Note: There is no need to consider the opposite case, with a + * rename/merge of the root directory into some subdirectory + * because as noted above the root directory always exists so it + * cannot be considered to be renamed. + */ + if (end_of_new == new_path && + end_of_old != old_path && end_of_old[-1] == '/') { + *old_dir = xstrndup(old_path, --end_of_old - old_path); + *new_dir = xstrdup(""); + return; + } /* * We've found the first non-matching character in the directory diff --git a/t/t6043-merge-rename-directories.sh b/t/t6043-merge-rename-directories.sh index c966147d5d..32cdd1f493 100755 --- a/t/t6043-merge-rename-directories.sh +++ b/t/t6043-merge-rename-directories.sh @@ -4051,6 +4051,120 @@ test_expect_success '12c-check: Moving one directory hierarchy into another w/ c ) ' +# Testcase 12d, Rename/merge of subdirectory into the root +# Commit O: a/b/subdir/foo +# Commit A: subdir/foo +# Commit B: a/b/subdir/foo, a/b/bar +# Expected: subdir/foo, bar + +test_expect_success '12d-setup: Rename/merge subdir into the root, variant 1' ' + test_create_repo 12d && + ( + cd 12d && + + mkdir -p a/b/subdir && + test_commit a/b/subdir/foo && + + git branch O && + git branch A && + git branch B && + + git checkout A && + mkdir subdir && + git mv a/b/subdir/foo.t subdir/foo.t && + test_tick && + git commit -m "A" && + + git checkout B && + test_commit a/b/bar + ) +' + +test_expect_success '12d-check: Rename/merge subdir into the root, variant 1' ' + ( + cd 12d && + + git checkout A^0 && + + git -c merge.directoryRenames=true merge -s recursive B^0 && + + git ls-files -s >out && + test_line_count = 2 out && + + git rev-parse >actual \ + HEAD:subdir/foo.t HEAD:bar.t && + git rev-parse >expect \ + O:a/b/subdir/foo.t B:a/b/bar.t && + test_cmp expect actual && + + git hash-object bar.t >actual && + git rev-parse B:a/b/bar.t >expect && + test_cmp expect actual && + + test_must_fail git rev-parse HEAD:a/b/subdir/foo.t && + test_must_fail git rev-parse HEAD:a/b/bar.t && + test_path_is_missing a/ && + test_path_is_file bar.t + ) +' + +# Testcase 12e, Rename/merge of subdirectory into the root +# Commit O: a/b/foo +# Commit A: foo +# Commit B: a/b/foo, a/b/bar +# Expected: foo, bar + +test_expect_success '12e-setup: Rename/merge subdir into the root, variant 2' ' + test_create_repo 12e && + ( + cd 12e && + + mkdir -p a/b && + test_commit a/b/foo && + + git branch O && + git branch A && + git branch B && + + git checkout A && + mkdir subdir && + git mv a/b/foo.t foo.t && + test_tick && + git commit -m "A" && + + git checkout B && + test_commit a/b/bar + ) +' + +test_expect_success '12e-check: Rename/merge subdir into the root, variant 2' ' + ( + cd 12e && + + git checkout A^0 && + + git -c merge.directoryRenames=true merge -s recursive B^0 && + + git ls-files -s >out && + test_line_count = 2 out && + + git rev-parse >actual \ + HEAD:foo.t HEAD:bar.t && + git rev-parse >expect \ + O:a/b/foo.t B:a/b/bar.t && + test_cmp expect actual && + + git hash-object bar.t >actual && + git rev-parse B:a/b/bar.t >expect && + test_cmp expect actual && + + test_must_fail git rev-parse HEAD:a/b/foo.t && + test_must_fail git rev-parse HEAD:a/b/bar.t && + test_path_is_missing a/ && + test_path_is_file bar.t + ) +' + ########################################################################### # SECTION 13: Checking informational and conflict messages # -- 2.39.2