nvda

928cf029 - Fix exception during textInfos.moveToCodepointOffset when some characters correspond to 0 pythonic characters (#16447)

Fix exception during textInfos.moveToCodepointOffset when some characters correspond to 0 pythonic characters (#16447) Partially closes #16406. Summary of the issue: When trying to navigate by style an exception is thrown: RuntimeError: Unable to find desired offset in TextInfo. Description of user facing changes N/A Description of development approach Investigation showed that in Outlook with word UIA enabled, sometimes there are characters that translate into 0 codepoint characters. To illustrate this further: >>> p=focus.treeInterceptor.makeTextInfo('caret') >>> p.expand('paragraph') >>> p.text 'View in browser' >>> p.collapse(end=True) >>> p.move('character', -1, 'start') -1 >>> p.text '' >>> len(p.text) 0 E.g. we move a collapsed text info start by -1 character, and the resulting textInfo still appears to be empty- at least its Python text is empty. I anticipated this to happen somewhere, but didn't encounter a single example when I was implementing moveToCodepointOffset function, so I missed one edge case. Now fixing this edge case. Also adding unit tests.