Visual diff stacktraces on Windows with 4.4-rc
Both Diff to Parent and Diff to Local are affected. I'm using BeyondCompare3, and I'm guessing it is related to registering merge-tools config. I can't reproduce this with core Mercurial, so I thought I'd start here.
#!python
** Mercurial version (4.4-rc+3-cab34bda259e). TortoiseHg version (4.3.1+151-35d16dcb03fe)
** Command: --nofork workbench
** CWD: C:\Users\Matt\Desktop
** Encoding: cp1252
** Extensions loaded: eol, rebase, convert, graphlog, patchbomb, extdiff, strip, mq, evolve
** Python version: 2.7.13 (v2.7.13:a06454b1afa1, Dec 17 2016, 20:53:40) [MSC v.1500 64 bit (AMD64)]
** Windows version: sys.getwindowsversion(major=6, minor=1, build=7601, platform=2, service_pack='Service Pack 1')
** Processor architecture: x64
** Qt-5.9.1 PyQt-5.9 QScintilla-2.10.1
Traceback (most recent call last):
File "tortoisehg\hgqt\repowidget.pyo", line 1683, in visualDiffToLocal
File "tortoisehg\hgqt\visdiff.pyo", line 249, in visualdiff
File "tortoisehg\util\hglib.pyo", line 400, in difftools
File "tortoisehg\util\hglib.pyo", line 350, in mergetools
File "mercurial\filemerge.pyo", line 110, in _findtool
File "mercurial\filemerge.pyo", line 119, in findexternaltool
TypeError: cannot concatenate 'str' and 'NoneType' objects