dirstate: add test for exceptions during updates Adds a test that checks if the working copy parent and the working copy are in a good state if an exception happens between the time the working copy parent is set and the time the actual updates are recorded in the dirstate.

dirstate: wrap setparent calls with begin/endparentchange (issue4353) This wraps all the locations of dirstate.setparent with the appropriate begin/endparentchange calls. This will prevent exceptions during those calls from causing incoherent dirstates (issue4353).

dirstate: add begin/endparentchange to dirstate It's possible for the dirstate to become incoherent (issue4353) if there is an exception in the middle of the dirstate parent and entries being written (like if the user ctrl+c's). This change adds begin/endparentchange which a future patch will require to be set before changing the dirstate parent. This will allow us to prevent writing the dirstate in the event of an exception while changing the parent.

parsers: avoid signed/unsigned comparison mismatch Based on warning from Microsoft Visual C++ 2008.

parsers: use correct type for file offset Now using Py_ssize_t instead of long to denote offset in file whose length is already measured using Py_ssize_t. Length and offset are now consistent. Based on warning from Microsoft Visual C++ 2008.

parsers: ensure correct return type for inline_scan The returned data type for inline_scan should be Py_ssize_t rather than long. Based on warning from Microsoft Visual C++ 2008.

parsers: fix typing issue when constructing Python integer object The passed variable is a Py_ssize_t, not a long, and consequently should use PyInt_FromSsize_t rather than PyInt-FromLong. Fixed based on warning from Microsoft Visual C++ 2008.

parsers: use bitmask type consistently in find_gca_candidates Normalized type usage in find_gca_candidates triggered by warning from Microsoft Visual C++ 2008.

revert: drop `lexist` check in the backup logic We are no longer trying to backup files that do not exist on disk. This check can be safely dropped.

revert: distinguish between deleted file and locally modified Locally modified needs a backup while a deleted file cannot be backed up because there is no file to backup.