In Kindle app trying to move to next paragraph via textInfo works incorrectly

[mltony]

Steps to reproduce:

1. Open Kindle app. Open a book that contains some graphics in the beginning. A good example is The Tiger in the Smoke - currently it needs to be purchased for $1.99.
2. Put the cursor at the very beginning and in NVDA python console:

   def startOffset(info):
       preTextInfo = info.copy()
       preTextInfo.expand(textInfos.UNIT_STORY)
       infoCollapsed = info.copy()
       infoCollapsed.collapse()
       preTextInfo.setEndPoint(infoCollapsed, "endToEnd")
       preText = preTextInfo.text
       return len(preText)
   
   >>> t=focus.treeInterceptor.makeTextInfo('caret')
   >>> startOffset(t)
   0
   >>> t.text
   ''
   >>> t.expand('paragraph')
   >>> t.collapse(True)
   >>> startOffset(t)
   1
   >>> t.expand('paragraph')
   >>> t.collapse(True)
   >>> startOffset(t)
   0
   >>> t.expand('paragraph')
   >>> t.collapse(True)
   >>> startOffset(t)
   0
   

Actual behavior:

TextInfo stays repeatedly at the very beginning of the document (startOffset(info) == 0) instead of moving one paragraph forward each time.

Expected behavior:

TextInfo should move forward.

NVDA logs, crash dumps and other attachments:

>>> type(t)
<class 'abc.ReviewCursorManager_RootProxyTextInfo'>

System configuration

NVDA installed/portable/running from source:

Running from source

NVDA version:

master

Windows version:

Windows 11

Name and version of other software in use when reproducing the issue:

Kindle appModule.productVersion: '2.3.5.70840'

Other information about your system:

Other questions

Does the issue still occur after restarting your computer?

yes

Have you tried any other versions of NVDA? If so, please report their behaviors.

No

If NVDA add-ons are disabled, is your problem still occurring?

Yes

Does the issue still occur after you run the COM Registration Fixing Tool in NVDA's tools menu?

N/A

[mltony]

More problems with Kindle textInfo: even textInfo.compareEndPoints() appears to return wrong result:

>>> t=focus.treeInterceptor.makeTextInfo('caret')
>>> t.expand('paragraph')
>>> focus.treeInterceptor._moveToNextParagraph(t, 'next')
True
>>> startOffset(t)
1
>>> tt = t.copy()
>>> tt.collapse(True)
>>> tt.expand('paragraph')
>>> startOffset(tt)
0
>>> tt.compareEndPoints(t, 'startToStart')
1

Basically it says that start point of tt goes after start point of t, but when I query offsets via provided startOffset() function I get the opposite ordering of textInfos.

[mltony]

Also textInfo.move() is broken as well:

>>> t=focus.treeInterceptor.makeTextInfo('caret')
>>> t.move('paragraph', 1)
0
>>> t.move('paragraph', 10)
10
>>> startOffset(t)
0

[seanbudd]

Does this issue effect the user in any way, or is this just an issue in the python console?
Can you add steps to reproduce on how this would affect a user?

[mltony]

This affects fancy quickNav commands - style navigation, vertical navigation, text navigation. I already disabled them in Kindle precisely due to this issue. So currently I don't know another way to repro this for the end user.