Add advanced setting to allow UIA in chromium based browsers

source/NVDAObjects/UIA/__init__.py

@@ -647,21 +647,41 @@ def _getTextWithFieldsForUIARange(self,rootElement,textRange,formatConfig,includ
 					if debug:
 						log.debug("NULL childRange. Skipping")
 					continue
-				clippedStart=clippedEnd=False
-				if index==lastChildIndex and childRange.CompareEndpoints(UIAHandler.TextPatternRangeEndpoint_Start,textRange,UIAHandler.TextPatternRangeEndpoint_End)>=0:
+				clippedStart = False
+				clippedEnd = False
+				if childRange.CompareEndpoints(
+					UIAHandler.TextPatternRangeEndpoint_End,
+					textRange,
+					UIAHandler.TextPatternRangeEndpoint_Start
+				) <= 0:
+					if debug:
+						log.debug("Child completely before textRange. Skipping")
+					continue
+				if childRange.CompareEndpoints(
+					UIAHandler.TextPatternRangeEndpoint_Start,
+					textRange,
+					UIAHandler.TextPatternRangeEndpoint_End
+				) >= 0:
 					if debug:
 						log.debug("Child at or past end of textRange. Breaking")
 					break
-				if index==lastChildIndex:
-					lastChildEndDelta=childRange.CompareEndpoints(UIAHandler.TextPatternRangeEndpoint_End,textRange,UIAHandler.TextPatternRangeEndpoint_End)
-					if lastChildEndDelta>0:
-						if debug:
-							log.debug(
-								"textRange ended part way through the child. "
-								"Crop end of childRange to fit"
-							)
-						childRange.MoveEndpointByRange(UIAHandler.TextPatternRangeEndpoint_End,textRange,UIAHandler.TextPatternRangeEndpoint_End)
-						clippedEnd=True
+				lastChildEndDelta = childRange.CompareEndpoints(
+					UIAHandler.TextPatternRangeEndpoint_End,
+					textRange,
+					UIAHandler.TextPatternRangeEndpoint_End
+				)
+				if lastChildEndDelta > 0:
+					if debug:
+						log.debug(
+							"textRange ended part way through the child. "
+							"Crop end of childRange to fit"
+						)
+					childRange.MoveEndpointByRange(
+						UIAHandler.TextPatternRangeEndpoint_End,
+						textRange,
+						UIAHandler.TextPatternRangeEndpoint_End
+					)
+					clippedEnd = True
 				childStartDelta=childRange.CompareEndpoints(UIAHandler.TextPatternRangeEndpoint_Start,tempRange,UIAHandler.TextPatternRangeEndpoint_End)
 				if childStartDelta>0:
 					# plain text before this child
@@ -893,7 +913,24 @@ def findOverlayClasses(self,clsList):
 				clsList.append(edge.EdgeList)
 			else:
 				clsList.append(edge.EdgeNode)
-		elif self.role == controlTypes.ROLE_DOCUMENT and UIAAutomationId == "Microsoft.Windows.PDF.DocumentView":
+		elif self.windowClassName == "Chrome_RenderWidgetHostHWND":
+			from . import chromium
+			from . import web
+			if (
+				self.UIATextPattern
+				and self.role == controlTypes.ROLE_DOCUMENT
+				and self.parent
+				and self.parent.role == controlTypes.ROLE_PANE
+			):
+				clsList.append(chromium.ChromiumUIADocument)
+			else:
+				if self.role == controlTypes.ROLE_LIST:
+					clsList.append(web.List)
+				clsList.append(chromium.ChromiumUIA)
+		elif (
+			self.role == controlTypes.ROLE_DOCUMENT
+			and self.UIAElement.cachedAutomationId == "Microsoft.Windows.PDF.DocumentView"
+		):
 			# PDFs
 			from . import edge
 			clsList.append(edge.EdgeHTMLRoot)

source/NVDAObjects/UIA/chromium.py

@@ -0,0 +1,62 @@
+# A part of NonVisual Desktop Access (NVDA)
+# This file is covered by the GNU General Public License.
+# See the file COPYING for more details.
+# Copyright (C) 2020 NV Access limited, Leonard de Ruijter
+
+import UIAHandler
+from . import web
+import controlTypes
+
+
+class ChromiumUIATextInfo(web.UIAWebTextInfo):
+
+	def _getFormatFieldAtRange(self, textRange, formatConfig, ignoreMixedValues=False):
+		formatField = super()._getFormatFieldAtRange(textRange, formatConfig, ignoreMixedValues=ignoreMixedValues)
+		# Headings are also exposed in the element tree,
+		# And therefore exposing in a formatField is redundant and causes duplicate reporting.
+		# So remove heading-level from the formatField if it exists.
+		try:
+			del formatField.field['heading-level']
+		except KeyError:
+			pass
+		return formatField
+
+	def _getControlFieldForObject(self, obj, isEmbedded=False, startOfNode=False, endOfNode=False):
+		field = super()._getControlFieldForObject(
+			obj,
+			isEmbedded=isEmbedded,
+			startOfNode=startOfNode,
+			endOfNode=endOfNode
+		)
+		# use the value of comboboxes as content.
+		if obj.role == controlTypes.ROLE_COMBOBOX:
+			field['content'] = obj.value
+		# Layout tables do not have the UIA table pattern
+		if field['role'] == controlTypes.ROLE_TABLE:
+			if not obj._getUIACacheablePropertyValue(UIAHandler.UIA_IsTablePatternAvailablePropertyId):
+				field['table-layout'] = True
+		# Currently no way to tell if author has explicitly set name.
+		# Therefore always report the name if the control is not of a type that
+		# by definition uses its name for content.
+		# this may cause some duplicate speaking,
+		# But that is currently better than nothing at all.
+		if not field.get('nameIsContent') and field.get('name'):
+			field['alwaysReportName'] = True
+		return field
+
+
+class ChromiumUIA(web.UIAWeb):
+	_TextInfo = ChromiumUIATextInfo
+
+
+class ChromiumUIATreeInterceptor(web.UIAWebTreeInterceptor):
+
+	def _get_documentConstantIdentifier(self):
+		return self.rootNVDAObject.parent._getUIACacheablePropertyValue(UIAHandler.UIA_AutomationIdPropertyId)
+
+
+class ChromiumUIADocument(ChromiumUIA):
+	treeInterceptorClass = ChromiumUIATreeInterceptor
+
+	def _get_shouldCreateTreeInterceptor(self):
+		return self.role == controlTypes.ROLE_DOCUMENT