git: fix up dirstate use of index

This was super-broken before, and somehow none of the existing
attempts to use this code tripped on the defects here. Sigh.

Differential Revision: https://phab.mercurial-scm.org/D8996

hgext/git/dirstate.py

@@ -1,311 +1,320 b''
 from __future__ import absolute_import
 
 import contextlib
 import errno
 import os
 
 from mercurial import (
     error,
     extensions,
     match as matchmod,
     node as nodemod,
     pycompat,
     scmutil,
     util,
 )
 from mercurial.interfaces import (
     dirstate as intdirstate,
     util as interfaceutil,
 )
 
 from . import gitutil
 
 pygit2 = gitutil.get_pygit2()
 
 
 def readpatternfile(orig, filepath, warn, sourceinfo=False):
     if not (b'info/exclude' in filepath or filepath.endswith(b'.gitignore')):
         return orig(filepath, warn, sourceinfo=False)
     result = []
     warnings = []
     with open(filepath, b'rb') as fp:
         for l in fp:
             l = l.strip()
             if not l or l.startswith(b'#'):
                 continue
             if l.startswith(b'!'):
                 warnings.append(b'unsupported ignore pattern %s' % l)
                 continue
             if l.startswith(b'/'):
                 result.append(b'rootglob:' + l[1:])
             else:
                 result.append(b'relglob:' + l)
     return result, warnings
 
 
 extensions.wrapfunction(matchmod, b'readpatternfile', readpatternfile)
 
 
 _STATUS_MAP = {}
 if pygit2:
     _STATUS_MAP = {
         pygit2.GIT_STATUS_CONFLICTED: b'm',
         pygit2.GIT_STATUS_CURRENT: b'n',
         pygit2.GIT_STATUS_IGNORED: b'?',
         pygit2.GIT_STATUS_INDEX_DELETED: b'r',
         pygit2.GIT_STATUS_INDEX_MODIFIED: b'n',
         pygit2.GIT_STATUS_INDEX_NEW: b'a',
         pygit2.GIT_STATUS_INDEX_RENAMED: b'a',
         pygit2.GIT_STATUS_INDEX_TYPECHANGE: b'n',
         pygit2.GIT_STATUS_WT_DELETED: b'r',
         pygit2.GIT_STATUS_WT_MODIFIED: b'n',
         pygit2.GIT_STATUS_WT_NEW: b'?',
         pygit2.GIT_STATUS_WT_RENAMED: b'a',
         pygit2.GIT_STATUS_WT_TYPECHANGE: b'n',
         pygit2.GIT_STATUS_WT_UNREADABLE: b'?',
         pygit2.GIT_STATUS_INDEX_MODIFIED | pygit2.GIT_STATUS_WT_MODIFIED: 'm',
     }
 
 
 @interfaceutil.implementer(intdirstate.idirstate)
 class gitdirstate(object):
     def __init__(self, ui, root, gitrepo):
         self._ui = ui
         self._root = os.path.dirname(root)
         self.git = gitrepo
         self._plchangecallbacks = {}
 
     def p1(self):
         try:
             return self.git.head.peel().id.raw
         except pygit2.GitError:
             # Typically happens when peeling HEAD fails, as in an
             # empty repository.
             return nodemod.nullid
 
     def p2(self):
         # TODO: MERGE_HEAD? something like that, right?
         return nodemod.nullid
 
     def setparents(self, p1, p2=nodemod.nullid):
         assert p2 == nodemod.nullid, b'TODO merging support'
         self.git.head.set_target(gitutil.togitnode(p1))
 
     @util.propertycache
     def identity(self):
         return util.filestat.frompath(
             os.path.join(self._root, b'.git', b'index')
         )
 
     def branch(self):
         return b'default'
 
     def parents(self):
         # TODO how on earth do we find p2 if a merge is in flight?
         return self.p1(), nodemod.nullid
 
     def __iter__(self):
         return (pycompat.fsencode(f.path) for f in self.git.index)
 
     def items(self):
         for ie in self.git.index:
             yield ie.path, None  # value should be a dirstatetuple
 
     # py2,3 compat forward
     iteritems = items
 
     def __getitem__(self, filename):
         try:
             gs = self.git.status_file(filename)
         except KeyError:
             return b'?'
         return _STATUS_MAP[gs]
 
     def __contains__(self, filename):
         try:
             gs = self.git.status_file(filename)
             return _STATUS_MAP[gs] != b'?'
         except KeyError:
             return False
 
     def status(self, match, subrepos, ignored, clean, unknown):
         # TODO handling of clean files - can we get that from git.status()?
         modified, added, removed, deleted, unknown, ignored, clean = (
             [],
             [],
             [],
             [],
             [],
             [],
             [],
         )
         gstatus = self.git.status()
         for path, status in gstatus.items():
             path = pycompat.fsencode(path)
             if status == pygit2.GIT_STATUS_IGNORED:
                 if path.endswith(b'/'):
                     continue
                 ignored.append(path)
             elif status in (
                 pygit2.GIT_STATUS_WT_MODIFIED,
                 pygit2.GIT_STATUS_INDEX_MODIFIED,
                 pygit2.GIT_STATUS_WT_MODIFIED
                 | pygit2.GIT_STATUS_INDEX_MODIFIED,
             ):
                 modified.append(path)
             elif status == pygit2.GIT_STATUS_INDEX_NEW:
                 added.append(path)
             elif status == pygit2.GIT_STATUS_WT_NEW:
                 unknown.append(path)
             elif status == pygit2.GIT_STATUS_WT_DELETED:
                 deleted.append(path)
             elif status == pygit2.GIT_STATUS_INDEX_DELETED:
                 removed.append(path)
             else:
                 raise error.Abort(
                     b'unhandled case: status for %r is %r' % (path, status)
                 )
 
         # TODO are we really always sure of status here?
         return (
             False,
             scmutil.status(
                 modified, added, removed, deleted, unknown, ignored, clean
             ),
         )
 
     def flagfunc(self, buildfallback):
         # TODO we can do better
         return buildfallback()
 
     def getcwd(self):
         # TODO is this a good way to do this?
         return os.path.dirname(
             os.path.dirname(pycompat.fsencode(self.git.path))
         )
 
     def normalize(self, path):
         normed = util.normcase(path)
         assert normed == path, b"TODO handling of case folding: %s != %s" % (
             normed,
             path,
         )
         return path
 
     @property
     def _checklink(self):
         return util.checklink(os.path.dirname(pycompat.fsencode(self.git.path)))
 
     def copies(self):
         # TODO support copies?
         return {}
 
     # # TODO what the heck is this
     _filecache = set()
 
     def pendingparentchange(self):
         # TODO: we need to implement the context manager bits and
         # correctly stage/revert index edits.
         return False
 
     def write(self, tr):
         # TODO: call parent change callbacks
 
         if tr:
 
             def writeinner(category):
                 self.git.index.write()
 
             tr.addpending(b'gitdirstate', writeinner)
         else:
             self.git.index.write()
 
     def pathto(self, f, cwd=None):
         if cwd is None:
             cwd = self.getcwd()
         # TODO core dirstate does something about slashes here
         assert isinstance(f, bytes)
         r = util.pathto(self._root, cwd, f)
         return r
 
     def matches(self, match):
         for x in self.git.index:
             p = pycompat.fsencode(x.path)
             if match(p):
                 yield p
 
     def normal(self, f, parentfiledata=None):
         """Mark a file normal and clean."""
         # TODO: for now we just let libgit2 re-stat the file. We can
         # clearly do better.
 
     def normallookup(self, f):
         """Mark a file normal, but possibly dirty."""
         # TODO: for now we just let libgit2 re-stat the file. We can
         # clearly do better.
 
     def walk(self, match, subrepos, unknown, ignored, full=True):
         # TODO: we need to use .status() and not iterate the index,
         # because the index doesn't force a re-walk and so `hg add` of
         # a new file without an intervening call to status will
         # silently do nothing.
         r = {}
         cwd = self.getcwd()
         for path, status in self.git.status().items():
             if path.startswith('.hg/'):
                 continue
             path = pycompat.fsencode(path)
             if not match(path):
                 continue
             # TODO construct the stat info from the status object?
             try:
                 s = os.stat(os.path.join(cwd, path))
             except OSError as e:
                 if e.errno != errno.ENOENT:
                     raise
                 continue
             r[path] = s
         return r
 
     def savebackup(self, tr, backupname):
         # TODO: figure out a strategy for saving index backups.
         pass
 
     def restorebackup(self, tr, backupname):
         # TODO: figure out a strategy for saving index backups.
         pass
 
     def add(self, f):
-        self.git.index.add(pycompat.fsdecode(f))
+        index = self.git.index
+        index.read()
+        index.add(pycompat.fsdecode(f))
+        index.write()
 
     def drop(self, f):
-        self.git.index.remove(pycompat.fsdecode(f))
+        index = self.git.index
+        index.read()
+        index.remove(pycompat.fsdecode(f))
+        index.write()
 
     def remove(self, f):
-        self.git.index.remove(pycompat.fsdecode(f))
+        index = self.git.index
+        index.read()
+        index.remove(pycompat.fsdecode(f))
+        index.write()
 
     def copied(self, path):
         # TODO: track copies?
         return None
 
     def prefetch_parents(self):
         # TODO
         pass
 
     @contextlib.contextmanager
     def parentchange(self):
         # TODO: track this maybe?
         yield
 
     def addparentchangecallback(self, category, callback):
         # TODO: should this be added to the dirstate interface?
         self._plchangecallbacks[category] = callback
 
     def clearbackup(self, tr, backupname):
         # TODO
         pass
 
     def setbranch(self, branch):
         raise error.Abort(
             b'git repos do not support branches. try using bookmarks'
         )