comparison mercurial/templater.py @ 24280:6c55e37ba5f2

templater: allow piping generator-type function output to filters

Template functions use "yield"s assuming that the result will be combined
into a string, which means both "f -> str" and "f -> generator" should behave
in the same way.

Before this patch, piping generator function resulted in a cryptic error.
We had to insert "|stringify" in this case.

  $ hg log --template '{if(author, author)|user}\n'
  abort: template filter 'userfilter' is not compatible with keyword
  '[(<function runsymbol at 0x7f5af2e8d8c0>, 'author'),
    (<function runsymbol at 0x7f5af2e8d8c0>, 'author')]'

24279:7cf9a9e0cf89

    filt = getfilter(exp[2], context)
    return (runfilter, (func, data, filt))

def runfilter(context, mapping, data):
    func, data, filt = data
    try:
        return filt(func(context, mapping, data))
    except (ValueError, AttributeError, TypeError):
        if isinstance(data, tuple):
            dt = data[1]
        else:
            dt = data

24280:6c55e37ba5f2

    filt = getfilter(exp[2], context)
    return (runfilter, (func, data, filt))

def runfilter(context, mapping, data):
    func, data, filt = data
    # func() may return string, generator of strings or arbitrary object such
    # as date tuple, but filter does not want generator.
    thing = func(context, mapping, data)
    if isinstance(thing, types.GeneratorType):
        thing = stringify(thing)
    try:
        return filt(thing)
    except (ValueError, AttributeError, TypeError):
        if isinstance(data, tuple):
            dt = data[1]
        else:
            dt = data