templatefilters: handle TypeError by count() Prepares for removing the weird exception catcher from runfilter().

keyword: declare input type of date filters as date Dropped redundant dateutil.parsedate(), which is now handled by the templater.

templatefilters: declare input type as date where appropriate I'm not sure if the templateutil.date type can be a thing. Currently it's just a constant.

templater: attach hint to input-type error of runfilter() Tests will be added by the next patch.

templatefuncs: use evaldate() where seems appropriate This means date("today") is allowed. Also fixes evaldate() to forcibly use the custom error message if specified.

templater: factor out function that parses argument as date tuple

templatefilters: declare input type as bytes where appropriate Some test outputs changed since input is now coerced to a byte string. I think that's okay. Maybe {date} should have some readable representation?

templatefilters: allow declaration of input data type Currently filters take an unwrapped value, which should have no hybrid magic but actually it does because stringify() relies on it. The 'intype' allows us to pre-process the magic by .e.g. evalstring() keeping filter functions as simple as they are now. stringify() is ported as an example. More follow.

hgweb: use registrar to declare "websub" template filter Prepares for adding 'intype' attribute.

procutil: redirect ui.fout to stderr while stdio is protected The new behavior seems slightly nicer as we can at least read the output. And this is similar to what the sshserver is doing, so we can probably reuse protectstdio() instead of the weird hook.redirect(True) hack.