The invert() method assumes that all subtypes are invertible. However,
the OT type invert() method is optional, so not all types will
have it implemented (rich-text is a notable example).
This change checks for presence of the invert() function, and throws
a more descriptive error if it's not present.
The
invert()method assumes that all subtypes are invertible. However, the OT typeinvert()method is optional, so not all types will have it implemented (rich-textis a notable example).This change checks for presence of the
invert()function, and throws a more descriptive error if it's not present.