flagutil: introduce a flagprocessorsmixin class
To avoid code duplication, we will provide a simple "ready to use" mixin that
carry the appropriate logic. First we use it in standard revlog, we'll remove
code duplication in later changesets.
Differential Revision: https://phab.mercurial-scm.org/D6796
--- a/mercurial/revlog.py Fri Sep 06 23:26:30 2019 -0700
+++ b/mercurial/revlog.py Thu Aug 08 01:12:48 2019 +0200
@@ -261,7 +261,7 @@
p = versionformat_pack(version) + p[4:]
return p
-class revlog(object):
+class revlog(flagutil.flagprocessorsmixin):
"""
the underlying revision storage object
@@ -1715,69 +1715,6 @@
"""
return storageutil.hashrevisionsha1(text, p1, p2)
- def _processflags(self, text, flags, operation, raw=False):
- """Inspect revision data flags and applies transforms defined by
- registered flag processors.
-
- ``text`` - the revision data to process
- ``flags`` - the revision flags
- ``operation`` - the operation being performed (read or write)
- ``raw`` - an optional argument describing if the raw transform should be
- applied.
-
- This method processes the flags in the order (or reverse order if
- ``operation`` is 'write') defined by REVIDX_FLAGS_ORDER, applying the
- flag processors registered for present flags. The order of flags defined
- in REVIDX_FLAGS_ORDER needs to be stable to allow non-commutativity.
-
- Returns a 2-tuple of ``(text, validatehash)`` where ``text`` is the
- processed text and ``validatehash`` is a bool indicating whether the
- returned text should be checked for hash integrity.
-
- Note: If the ``raw`` argument is set, it has precedence over the
- operation and will only update the value of ``validatehash``.
- """
- # fast path: no flag processors will run
- if flags == 0:
- return text, True
- if not operation in ('read', 'write'):
- raise error.ProgrammingError(_("invalid '%s' operation") %
- operation)
- # Check all flags are known.
- if flags & ~flagutil.REVIDX_KNOWN_FLAGS:
- raise error.RevlogError(_("incompatible revision flag '%#x'") %
- (flags & ~flagutil.REVIDX_KNOWN_FLAGS))
- validatehash = True
- # Depending on the operation (read or write), the order might be
- # reversed due to non-commutative transforms.
- orderedflags = REVIDX_FLAGS_ORDER
- if operation == 'write':
- orderedflags = reversed(orderedflags)
-
- for flag in orderedflags:
- # If a flagprocessor has been registered for a known flag, apply the
- # related operation transform and update result tuple.
- if flag & flags:
- vhash = True
-
- if flag not in self._flagprocessors:
- message = _("missing processor for flag '%#x'") % (flag)
- raise error.RevlogError(message)
-
- processor = self._flagprocessors[flag]
- if processor is not None:
- readtransform, writetransform, rawtransform = processor
-
- if raw:
- vhash = rawtransform(self, text)
- elif operation == 'read':
- text, vhash = readtransform(self, text)
- else: # write operation
- text, vhash = writetransform(self, text)
- validatehash = validatehash and vhash
-
- return text, validatehash
-
def checkhash(self, text, node, p1=None, p2=None, rev=None):
"""Check node hash integrity.
--- a/mercurial/revlogutils/flagutil.py Fri Sep 06 23:26:30 2019 -0700
+++ b/mercurial/revlogutils/flagutil.py Thu Aug 08 01:12:48 2019 +0200
@@ -78,3 +78,74 @@
msg = _("cannot register multiple processors on flag '%#x'.") % (flag)
raise error.Abort(msg)
flagprocessors[flag] = processor
+
+class flagprocessorsmixin(object):
+ """basic mixin to support revlog flag processing
+
+ Make sure the `_flagprocessors` attribute is set at ``__init__`` time.
+
+ See the documentation of the ``_processflags`` method for details.
+ """
+
+ def _processflags(self, text, flags, operation, raw=False):
+ """Inspect revision data flags and applies transforms defined by
+ registered flag processors.
+
+ ``text`` - the revision data to process
+ ``flags`` - the revision flags
+ ``operation`` - the operation being performed (read or write)
+ ``raw`` - an optional argument describing if the raw transform should be
+ applied.
+
+ This method processes the flags in the order (or reverse order if
+ ``operation`` is 'write') defined by REVIDX_FLAGS_ORDER, applying the
+ flag processors registered for present flags. The order of flags defined
+ in REVIDX_FLAGS_ORDER needs to be stable to allow non-commutativity.
+
+ Returns a 2-tuple of ``(text, validatehash)`` where ``text`` is the
+ processed text and ``validatehash`` is a bool indicating whether the
+ returned text should be checked for hash integrity.
+
+ Note: If the ``raw`` argument is set, it has precedence over the
+ operation and will only update the value of ``validatehash``.
+ """
+ # fast path: no flag processors will run
+ if flags == 0:
+ return text, True
+ if not operation in ('read', 'write'):
+ raise error.ProgrammingError(_("invalid '%s' operation") %
+ operation)
+ # Check all flags are known.
+ if flags & ~REVIDX_KNOWN_FLAGS:
+ raise error.RevlogError(_("incompatible revision flag '%#x'") %
+ (flags & ~REVIDX_KNOWN_FLAGS))
+ validatehash = True
+ # Depending on the operation (read or write), the order might be
+ # reversed due to non-commutative transforms.
+ orderedflags = REVIDX_FLAGS_ORDER
+ if operation == 'write':
+ orderedflags = reversed(orderedflags)
+
+ for flag in orderedflags:
+ # If a flagprocessor has been registered for a known flag, apply the
+ # related operation transform and update result tuple.
+ if flag & flags:
+ vhash = True
+
+ if flag not in self._flagprocessors:
+ message = _("missing processor for flag '%#x'") % (flag)
+ raise error.RevlogError(message)
+
+ processor = self._flagprocessors[flag]
+ if processor is not None:
+ readtransform, writetransform, rawtransform = processor
+
+ if raw:
+ vhash = rawtransform(self, text)
+ elif operation == 'read':
+ text, vhash = readtransform(self, text)
+ else: # write operation
+ text, vhash = writetransform(self, text)
+ validatehash = validatehash and vhash
+
+ return text, validatehash