tests: use 'f' in test-merge-criss-cross.t to prepare for recursive dumping Prepare for adding a test case with files in a directory.

util: make sortdict.keys() return a copy dict.keys() is documented to return a copy, so it's surprising that sortdict.keys() did not. I noticed this because we have an extension that calls readlocaltags(). That method tries to remove any tags that point to non-existent revisions (most likely stripped). However, since it's unintentionally working on the instance it's modifying, it sometimes fails to remove tags when there are multiple bad tags in a row. This was not caught because localrepo.tags() does an additional layer of filtering. sortdict is also used in other places, but I have not checked whether its keys() and/or __delitem__() methods are used there.

test-highlight: add normalization rule for Pygments 2.2 The test failed on Debian sid because of new class="vm".

tests: account for different newline behavior between Solaris and GNU grep GNU grep, when emitting a matching line that doesn't have a terminating newline, will add an extra newline. Solaris grep passes the original line through without the newline. This causes differences in test output when looking at the last line of the output of get-with-headers.py, which doesn't usually emit (and certainly doesn't guarantee) a terminating newline. Both grep implementations succeed in matching the requested pattern, though, so rely on specifying the full pattern on grep's commandline instead of expecting it in the output, and send the output to /dev/null.