def from_json(self, json: Map) -> Maybe[Project]:
''' Try to instantiate a Project from the given json object.
Convert the **type** key to **tpe** and its value to
Maybe.
Make sure **root** is a directory, fall back to resolution
by **tpe/name**.
Reinsert the root dir into the json dict, filter out all keys
that aren't contained in Project's fields.
Try to instantiate.
'''
root = json.get('root')\
.map(mkpath)\
.or_else(
json.get_all('type', 'name')
.flat_smap(self.resolver.type_name))
valid_fields = root\
.map(lambda a: json ** Map(root=a, tpe=json.get('type')))\
.map(lambda a: a.at(*Project._pclass_fields))
return Maybe.from_call(lambda: valid_fields.ssmap(Project)) | Empty()
def main_dir(self) -> Maybe[Path]:
return Maybe.from_call(Path.cwd, exc=IOError)
def setup(self):
self.cwd = Maybe.from_call(Path.cwd, exc=IOError)
super().setup()
def sub_path(base: Path, path: Path):
check = lambda: path.relative_to(str(base))
return Maybe.from_call(check, exc=ValueError)\
.map(_.parts)\
.map(List.wrap)
def ref(self, name):
return Maybe.from_call(lambda: self.repo.refs[name.encode()],
exc=KeyError)
