Defining optional checks?

[madig]

Sometimes, we might want to define a check that is only useful to some families and should not run by default. How to do this elegantly?

[graphicore]

there's a conditions keyword argument for the @check decorator which let's you define conditions under which to skip a check execution. Or, again, the check_skip_filter of a spec, depending on your use case.

There are examples of conditions usage in many specs. E.g. in hmtx.py:

@check(
  id = 'com.google.fonts/check/050',
  conditions = ['not missing_whitespace_chars']
)

or in googlefonts.py:

@check(
  id = 'com.google.fonts/check/095',
  conditions=['font_metadata', 'style']
)

[madig]

Hm. I was thinking of enabling tests for specific families without hardcoding their names into the specification object. Or making the test not run unless explicitly included with -c or something similar.

[davelab6]

If they are specific families, how do you want to specify them? :)

[graphicore]

"without hardcoding their names into the specification object."

You can use expected_values in your spec. These can

• a) have default values
• b) be overridden by other specs using "force=True", thus you can define an empty whitelist and another spec can override it, there are real world examples of this.
• c) can be set (just like fonts) in the constructor of CheckRunner

You'd combine this with the mentioned conditons kw-arg.

[justvanrossum]

Coming across this issue while looking for an answer to the original question (at least how I read it). As a fontbakery newbie, the answers given here unfortunately don't help me much.

What would help my situation would be two things:

• Checks that are not run by default
• A way to include those checks from the command-line, say with a argument called --include-checkid, which (unlike --checkid) does not turn everything else off.

Is there currently a way to do such a thing?