Move the isOffscreen logic from nvaccess#9735 to a function in UIAUti…

…ls and disable the console bounds checking code when oldRange is also offscreen.

source/NVDAObjects/UIA/winConsoleUIA.py

@@ -13,6 +13,7 @@
 import UIAHandler
 
 from scriptHandler import script
+from UIAUtils import isTextRangeOffscreen
 from winVersion import isWin10
 from . import UIATextInfo
 from ..behaviors import Terminal
@@ -50,8 +51,6 @@ def move(self, unit, direction, endPoint=None):
 			visiRanges = self.obj.UIATextPattern.GetVisibleRanges()
 			visiLength = visiRanges.length
 			if visiLength > 0:
-				firstVisiRange = visiRanges.GetElement(0)
-				lastVisiRange = visiRanges.GetElement(visiLength - 1)
 				oldRange = self._rangeObj.clone()
 		if unit == textInfos.UNIT_WORD and direction != 0:
 			# UIA doesn't implement word movement, so we need to do it manually.
@@ -108,13 +107,11 @@ def move(self, unit, direction, endPoint=None):
 		else:  # moving by a unit other than word
 			res = super(consoleUIATextInfo, self).move(unit, direction,
 														endPoint)
-		if oldRange and (
-			self._rangeObj.CompareEndPoints(
-				UIAHandler.TextPatternRangeEndpoint_Start, firstVisiRange,
-				UIAHandler.TextPatternRangeEndpoint_Start) < 0
-			or self._rangeObj.CompareEndPoints(
-				UIAHandler.TextPatternRangeEndpoint_Start, lastVisiRange,
-				UIAHandler.TextPatternRangeEndpoint_End) >= 0):
+		if (
+			oldRange
+			and isTextRangeOffscreen(self._rangeObj, visiRanges)
+			and not isTextRangeOffscreen(oldRange, visiRanges)
+		):
 			self._rangeObj = oldRange
 			return 0
 		return res

source/UIAUtils.py

@@ -172,6 +172,24 @@ def getChildrenWithCacheFromUIATextRange(textRange,cacheRequest):
 	c=CacheableUIAElementArray(c)
 	return c
 
+def isTextRangeOffscreen(range, visiRanges):
+	"""Given a UIA text range and a visible ranges array (returned from obj.UIATextPattern.GetVisibleRanges), determines if the given range is not within the visible ranges."""
+	visiLength = visiRanges.length
+	if visiLength > 0:
+		firstVisiRange = visiRanges.GetElement(0)
+		lastVisiRange = visiRanges.GetElement(visiLength - 1)
+		return range.CompareEndPoints(
+			UIAHandler.TextPatternRangeEndpoint_Start, firstVisiRange,
+			UIAHandler.TextPatternRangeEndpoint_Start
+		) < 0 or range.CompareEndPoints(
+			UIAHandler.TextPatternRangeEndpoint_Start, lastVisiRange,
+			UIAHandler.TextPatternRangeEndpoint_End) >= 0
+	else:
+		# Visible ranges not available, so fail gracefully.
+		log.warning("UIA visible ranges not available.")
+		return True
+
+
 class UIATextRangeAttributeValueFetcher(object):
 
 	def __init__(self,textRange):