We were previously processing entries in mapping files (when
`--mappings-are-raw` is not given) with
`.decode('unicode_escape').encode('utf8')` to replace backslash escape
sequences in bytestrings with the utf-8 encoded characters they
represent. However, it turns out that `.decode
('unicode_escape')` assumes latin-1 encoding if it encounters non-ascii
bytes: https://bugs.python.org/issue21331. So this gave incorrect
results if non-ascii utf8 data was present in the mapping.
To fix this, we now add an extra layer of `.decode('utf8').encode
('unicode-escape')` in order to convert any non-ascii characters into
their backslash escape sequences. Then the subsequent
`.decode('unicode_escape')` only encounters ascii characters and gives
correct results.
hg-fast-export.sanitize_name expects branch name to be a bytes
object. Command line parser gives out str objects. Convert
possible str object to bytes in hg2git.set_default_branch().
Mercurial internally stores (most) filepaths using forward slashes, and
returns them as such from its Python API, even on Windows.
So the splitting up of filepaths with `os.path.sep` was incorrect,
resulting in `.git` files (those within a subdirectory, anyway)
not being ignored on Windows as intended. Splitting on `b'/'` regardless
of OS fixes this.
On Python 3, `b'%s' % None` fails with a TypeError. In verify_heads,
an error message prints the sha1 of a git commit, but that sha1
can be None.
This commit instead prints `b'<None>'` if sha1 is None.
When checking that python has the mercurial package in hg-fast-export.sh,
use the same import statement that is used in hg-fast-export.py.
hg-fast-export.py imports revsymbol from mercurial.scmutil,
which was introduced in mercurial 4.6, but Ubuntu 18.04 only has
mercurial 4.5.3 using python2, so an incompatible python version may be
chosen without this change.
In Python 3, `sys.stderr.write()` requires unicode strings, and all
output on standard streams is UTF8 encoded. Therefore in the port to
Python 3, we `.decode()`d all strings that are used in `%` formatting of
strings to be printed to stderr.
However, in Python 2, `sys.stderr` accepts either bytestrings or unicode
strings, and:
- `%s` formatting of a bytestring with a unicode string, i.e `"%s" %
u"foo"` results in a unicode string.
- Writing a unicode string to stderr/stdout uses that stream's encoding
- When the output of the process is being piped somewhere other than a
terminal (as it is when called with pipes and shell redirection from
hg-fast-export.sh), that encoding is None, which implies ASCII.
- This raises UnicodeEncodeError if the unicode strings passed to
`stderr.write()` have non-ascii characters.
We cannot fix this problem simply by encoding UTF8 again before writing
to stderr on Python 2. This is because the *decoding* of filenames with
the UTF8 codec may fail - filenames may not even be valid UTF8 desite
this being the declared filesystem encoding.
We could `fsdecode()` filenames on Python 3, which would use the
`surrogateescape` error handler, but stderr does not use this error
handler for output, meaning we would just have to encode again (with the
same error handler) anyway. And Python 2 lacks the `surrogateescape`
error handler in any case - we would need to reimplement it just to do a
round-trip decode and encode for no reason.
This commit leaves filenames and other repository data as bytestrings,
and simply writes them to `sys.stderr.buffer` on Python 3 or
`sys.stderr` on Python 2 as-is, after `%` formatting with bytestring
literals. This avoids encoding issues of filenames altogether.
Other writing to stderr that does not involve repository data has been
left with "native" strings, i.e.
`sys.stderr.write("a string literal %s" % a_command_line_arg)`. These
will still fail on Python 3 if the user passes a non-UTF filename as a
command line argument or similar. This is acceptable IMHO - although
`hg-fast-export` may encounter invalid UTF8 in mercurial repositories,
it is not too much to impose that the user name their branch mapping
files etc with valid UTF8!
Port hg-fast-import to Python 2/3 polyglot code.
Since mercurial accepts and returns bytestrings for all repository data,
the approach I've taken here is to use bytestrings throughout the
hg-fast-import code. All strings pertaining to repository data are
bytestrings. This means the code is using the same string datatype for
this data on Python 3 as it did (and still does) on Python 2.
Repository data coming from subprocess calls to git, or read from files,
is also left as the bytestrings either returned from
subprocess.check_output or as read from the file in 'rb' mode.
Regexes and string literals that are used with repository data have
all had a b'' prefix added.
When repository data is used in error/warning messages, it is decoded
with the UTF8 codec for printing.
With this patch, hg-fast-export.py writes binary output to
sys.stdout.buffer on Python 3 - on Python 2 this doesn't exist and it
still uses sys.stdout.
The only strings that are left as "native" strings and not coerced to
bytestrings are filepaths passed in on the command line, and dictionary
keys for internal data structures used by hg-fast-import.py, that do
not originate in repository data.
Mapping files are read in 'rb' mode, and thus bytestrings are read from
them. When an encoding is given, their contents are decoded with that
encoding, but then immediately encoded again with UTF8 and they are
returned as the resulting bytestrings
Other necessary changes were:
- indexing byestrings with a single index returns an integer on Python.
These indexing operations have been replaced with a one-element
slice: x[0] -> x[0:1] or x[-1] -> [-1:] so at to return a bytestring.
- raw_hash.encode('hex_codec') replaced with binascii.hexlify(raw_hash)
- str(integer) -> b'%d' % integer
- 'string_escape' codec replaced with 'unicode_escape' (which was
backported to python 2.7). Strings decoded with this codec were then
immediately re-encoded with UTF8.
- Calls to map() intended to execute their contents immediately were
unwrapped or converted to list comprehensions, since map() is an
iterator and does not execute until iterated over.
hg-fast-export.sh has been modified to not require Python 2. Instead, if
PYTHON has not been defined, it checks python2, python, then python3,
and uses the first one that exists and can import the mercurial module.
Status has always been a tuple, but since 5.3, commit:
https://www.mercurial-scm.org/repo/hg/rev/c5548b0b6847, it is an object.
Therefore the __getitem__ of the tuple isn't available anymore.
This fix is compatible with mercurial>=4.6, as the old status tuple
still has the same properties.
- Allow skipping writing the branch name if the branch is 'master'.
- Allow writing the branch name on the same line as the first line of
the commit message separated by a colon, instead of it having its own
line.
This reverts commit 0c5617bf8d.
The changes turned out to require bash. Traditionally we have tried to
stay compatible with plain old sh, so this is a revert.
Closes#195.
Document the default behavior of renaming the `default` hg branch to `master`
on git, and how to override from the command line when this causes problems.
See also: #182
Mercurial supports not only submodules which are Mercurial
repositories, but also Git and Subversion repositories. This
patch adds support for submodules which are Git repositories to
hg-fast-export.
As submodules which are Git repositories won't need a mapping
file we trigger the submodule update only on the occurence of the
`.hgsubstate` file and push the check for a valid
`submodule_mappings` to `refresh_gitmodules(ctx)`
Obsolete changesets are, for example, create by the Evolve
extension. This patch switches to an unfiltered repository (the
filtered one throws on an attempt to access obsolete revisions) and
then filters out the obsolete revisions when it comes across them.
Fixes#173
When version v171002 introduced a new mapping file format for branches
and authors, that change never made it to the remapping of tags
although the README documents it.
Fixes#172.
Make it possible to completely disable the name sanitizer by the
--no-auto-sanitize flag. Previously the sanitizer was run on user
remapped names. As the sanitizer rewrites perfectly legal git
names (such as __.*) this is probably not what the user wants.
Closes#155.
