py3: fix bytes/unicode issues in convert/darcs

- don't check for a binary symbol in globals(), which meant it always thought
  the module wasn't available
- don't pass bytes to stdlib methods
- return bytes in getchanges where Mercurial expects to see them

hgext/convert/darcs.py

@@ -1,222 +1,223 b''
 # darcs.py - darcs support for the convert extension
 #
 #  Copyright 2007-2009 Olivia Mackall <[e-mail]> and others
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 import os
 import re
 import shutil
 from xml.etree.ElementTree import (
     ElementTree,
     XMLParser,
 )
 
 from mercurial.i18n import _
 from mercurial import (
     error,
     pycompat,
     util,
 )
 from mercurial.utils import dateutil
 from . import common
 
 NoRepo = common.NoRepo
 
 
 class darcs_source(common.converter_source, common.commandline):
     def __init__(self, ui, repotype, path, revs=None):
         common.converter_source.__init__(self, ui, repotype, path, revs=revs)
         common.commandline.__init__(self, ui, b'darcs')
 
         # check for _darcs, ElementTree so that we can easily skip
         # test-convert-darcs if ElementTree is not around
         if not os.path.exists(os.path.join(path, b'_darcs')):
             raise NoRepo(_(b"%s does not look like a darcs repository") % path)
 
         common.checktool(b'darcs')
         version = self.run0(b'--version').splitlines()[0].strip()
         if version < b'2.1':
             raise error.Abort(
                 _(b'darcs version 2.1 or newer needed (found %r)') % version
             )
 
-        if b"ElementTree" not in globals():
+        if "ElementTree" not in globals():
             raise error.Abort(_(b"Python ElementTree module is not available"))
 
         self.path = os.path.realpath(path)
 
         self.lastrev = None
         self.changes = {}
         self.parents = {}
         self.tags = {}
 
         # Check darcs repository format
         format = self.format()
         if format:
             if format in (b'darcs-1.0', b'hashed'):
                 raise NoRepo(
                     _(
                         b"%s repository format is unsupported, "
                         b"please upgrade"
                     )
                     % format
                 )
         else:
             self.ui.warn(_(b'failed to detect repository format!'))
 
     def before(self):
         self.tmppath = pycompat.mkdtemp(
             prefix=b'convert-' + os.path.basename(self.path) + b'-'
         )
         output, status = self.run(b'init', repodir=self.tmppath)
         self.checkexit(status)
 
         tree = self.xml(
             b'changes', xml_output=True, summary=True, repodir=self.path
         )
         tagname = None
         child = None
-        for elt in tree.findall(b'patch'):
-            node = elt.get(b'hash')
-            name = elt.findtext(b'name', b'')
+        for elt in tree.findall('patch'):
+            node = self.recode(elt.get('hash'))
+            name = self.recode(elt.findtext('name', ''))
             if name.startswith(b'TAG '):
                 tagname = name[4:].strip()
             elif tagname is not None:
                 self.tags[tagname] = node
                 tagname = None
             self.changes[node] = elt
             self.parents[child] = [node]
             child = node
         self.parents[child] = []
 
     def after(self):
         self.ui.debug(b'cleaning up %s\n' % self.tmppath)
         shutil.rmtree(self.tmppath, ignore_errors=True)
 
     def recode(self, s, encoding=None):
         if isinstance(s, str):
             # XMLParser returns unicode objects for anything it can't
             # encode into ASCII. We convert them back to str to get
             # recode's normal conversion behavior.
             s = s.encode('latin-1')
         return super(darcs_source, self).recode(s, encoding)
 
     def xml(self, cmd, **kwargs):
         # NOTE: darcs is currently encoding agnostic and will print
         # patch metadata byte-for-byte, even in the XML changelog.
         etree = ElementTree()
         # While we are decoding the XML as latin-1 to be as liberal as
         # possible, etree will still raise an exception if any
         # non-printable characters are in the XML changelog.
-        parser = XMLParser(encoding=b'latin-1')
+        parser = XMLParser(encoding='latin-1')
         p = self._run(cmd, **kwargs)
         etree.parse(p.stdout, parser=parser)
         p.wait()
         self.checkexit(p.returncode)
         return etree.getroot()
 
     def format(self):
         output, status = self.run(b'show', b'repo', repodir=self.path)
         self.checkexit(status)
-        m = re.search(r'^\s*Format:\s*(.*)$', output, re.MULTILINE)
+        m = re.search(br'^\s*Format:\s*(.*)$', output, re.MULTILINE)
         if not m:
             return None
         return b','.join(sorted(f.strip() for f in m.group(1).split(b',')))
 
     def manifest(self):
         man = []
         output, status = self.run(
             b'show', b'files', no_directories=True, repodir=self.tmppath
         )
         self.checkexit(status)
         for line in output.split(b'\n'):
             path = line[2:]
             if path:
                 man.append(path)
         return man
 
     def getheads(self):
         return self.parents[None]
 
     def getcommit(self, rev):
         elt = self.changes[rev]
         dateformat = b'%a %b %d %H:%M:%S %Z %Y'
-        date = dateutil.strdate(elt.get(b'local_date'), dateformat)
-        desc = elt.findtext(b'name') + b'\n' + elt.findtext(b'comment', b'')
+        date = dateutil.strdate(elt.get('local_date'), dateformat)
+        desc = elt.findtext('name') + '\n' + elt.findtext('comment', '')
         # etree can return unicode objects for name, comment, and author,
         # so recode() is used to ensure str objects are emitted.
         newdateformat = b'%Y-%m-%d %H:%M:%S %1%2'
         return common.commit(
-            author=self.recode(elt.get(b'author')),
+            author=self.recode(elt.get('author')),
             date=dateutil.datestr(date, newdateformat),
             desc=self.recode(desc).strip(),
             parents=self.parents[rev],
         )
 
     def pull(self, rev):
         output, status = self.run(
             b'pull',
             self.path,
             all=True,
-            match=b'hash %s' % rev,
+            match=b'hash %s' % self.recode(rev),
             no_test=True,
             no_posthook=True,
             external_merge=b'/bin/false',
             repodir=self.tmppath,
         )
         if status:
             if output.find(b'We have conflicts in') == -1:
                 self.checkexit(status, output)
             output, status = self.run(b'revert', all=True, repodir=self.tmppath)
             self.checkexit(status, output)
 
     def getchanges(self, rev, full):
         if full:
             raise error.Abort(_(b"convert from darcs does not support --full"))
         copies = {}
         changes = []
         man = None
-        for elt in self.changes[rev].find(b'summary').getchildren():
-            if elt.tag in (b'add_directory', b'remove_directory'):
+        for elt in self.changes[rev].find('summary').getchildren():
+            if elt.tag in ('add_directory', 'remove_directory'):
                 continue
-            if elt.tag == b'move':
+            if elt.tag == 'move':
                 if man is None:
                     man = self.manifest()
-                source, dest = elt.get(b'from'), elt.get(b'to')
+                source = self.recode(elt.get('from'))
+                dest = self.recode(elt.get('to'))
                 if source in man:
                     # File move
                     changes.append((source, rev))
                     changes.append((dest, rev))
                     copies[dest] = source
                 else:
                     # Directory move, deduce file moves from manifest
                     source = source + b'/'
                     for f in man:
                         if not f.startswith(source):
                             continue
                         fdest = dest + b'/' + f[len(source) :]
                         changes.append((f, rev))
                         changes.append((fdest, rev))
                         copies[fdest] = f
             else:
-                changes.append((elt.text.strip(), rev))
+                changes.append((self.recode(elt.text.strip()), rev))
         self.pull(rev)
         self.lastrev = rev
         return sorted(changes), copies, set()
 
     def getfile(self, name, rev):
         if rev != self.lastrev:
             raise error.Abort(_(b'internal calling inconsistency'))
         path = os.path.join(self.tmppath, name)
         try:
             data = util.readfile(path)
             mode = os.lstat(path).st_mode
         except FileNotFoundError:
             return None, None
         mode = (mode & 0o111) and b'x' or b''
         return data, mode
 
     def gettags(self):
         return self.tags