From: Tao Klerks <tao@xxxxxxxxxx> Perforce has a file type "utf8" which represents a text file with explicit BOM. utf8-encoded files *without* BOM are stored as regular file type "text". The "utf8" file type behaves like text in all but one important way: it is stored, internally, without the leading 3 BOM bytes. git-p4 has historically imported utf8-with-BOM files (files stored, in Perforce, as type "utf8") the same way as regular text files - losing the BOM in the process. Under most circumstances this issue has little functional impact, as most systems consider the BOM to be optional and redundant, but this *is* a correctness failure, and can have lead to practical issues for example when BOMs are explicitly included in test files, for example in a file encoding test suite. Fix the handling of utf8-with-BOM files when importing changes from p4 to git, and introduce a test that checks it is working correctly. Signed-off-by: Tao Klerks <tao@xxxxxxxxxx> --- git-p4: preserve utf8 BOM when importing from p4 to git I manually tested these changes with python2 and python3 - I don't know whether there is a more rigorous approach possible than changing the system default python and rerunning the "t98xx" tests, but that did work (and initially highlighted an issue, now fixed). Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1203%2FTaoK%2Fgit-p4-utf8-bom-v1 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1203/TaoK/git-p4-utf8-bom-v1 Pull-Request: https://github.com/gitgitgadget/git/pull/1203 git-p4.py | 10 ++++++++++ t/t9802-git-p4-filetype.sh | 34 ++++++++++++++++++++++++++++++++++ 2 files changed, 44 insertions(+) diff --git a/git-p4.py b/git-p4.py index a9b1f904410..6d932e7ed76 100755 --- a/git-p4.py +++ b/git-p4.py @@ -2885,6 +2885,16 @@ class P4Sync(Command, P4UserMap): print("\nIgnoring apple filetype file %s" % file['depotFile']) return + if type_base == "utf8": + # The type utf8 explicitly means utf8 *with BOM*. These are + # streamed just like regular text files, however, without + # the BOM in the stream. + # Therefore, to accurately import these files into git, we + # need to explicitly re-add the BOM before writing. + # 'contents' is a set of bytes in this case, so create the + # BOM prefix as a b'' literal. + contents = [b'\xef\xbb\xbf' + contents[0]] + contents[1:] + # Note that we do not try to de-mangle keywords on utf16 files, # even though in theory somebody may want that. regexp = p4_keywords_regexp_for_type(type_base, type_mods) diff --git a/t/t9802-git-p4-filetype.sh b/t/t9802-git-p4-filetype.sh index 19073c6e9f8..2a6ee2a4678 100755 --- a/t/t9802-git-p4-filetype.sh +++ b/t/t9802-git-p4-filetype.sh @@ -333,4 +333,38 @@ test_expect_success SYMLINKS 'empty symlink target' ' ) ' +test_expect_success SYMLINKS 'utf-8 with and without BOM in text file' ' + ( + cd "$cli" && + + # some utf8 content + echo some tǣxt >utf8-nobom-test && + + # same utf8 content as before but with bom + echo some tǣxt | sed '\''s/^/\xef\xbb\xbf/'\'' >utf8-bom-test && + + # bom only + dd bs=1 count=3 if=utf8-bom-test of=utf8-bom-empty-test && + + p4 add utf8-nobom-test utf8-bom-test utf8-bom-empty-test && + p4 submit -d "add utf8 test files" + ) && + test_when_finished cleanup_git && + + git p4 clone --dest="$git" //depot@all && + ( + cd "$git" && + git checkout refs/remotes/p4/master && + + echo some tǣxt >utf8-nobom-check && + test_cmp utf8-nobom-check utf8-nobom-test && + + echo some tǣxt | sed '\''s/^/\xef\xbb\xbf/'\'' >utf8-bom-check && + test_cmp utf8-bom-check utf8-bom-test && + + dd bs=1 count=3 if=utf8-bom-check of=utf8-bom-empty-check && + test_cmp utf8-bom-empty-check utf8-bom-empty-test + ) +' + test_done base-commit: 4b6846d9dcd391164b72bd70e8a0c0e09776afe3 -- gitgitgadget