Fix null-reference exception in TextAreaAutomationPeer - that was randomly occuring in the application.

sloutsky · sloutsky · commit 09f7dec79b2a · 2020-06-06T13:49:20.000+03:00
diff --git a/ICSharpCode.AvalonEdit/Editing/TextAreaAutomationPeer.cs b/ICSharpCode.AvalonEdit/Editing/TextAreaAutomationPeer.cs
@@ -114,8 +114,11 @@ public override object GetPattern(PatternInterface patternInterface)
 				return this;
 			if (patternInterface == PatternInterface.Scroll) {
 				TextEditor editor = TextArea.GetService(typeof(TextEditor)) as TextEditor;
-				if (editor != null)
-					return FromElement(editor).GetPattern(patternInterface);
+				if (editor != null) {
+					var fromElement = FromElement(editor);
+					if (fromElement != null)
+						fromElement.GetPattern(patternInterface);
+				}
 			}
 			return base.GetPattern(patternInterface);
 		}

Original file line number	Diff line number	Diff line change
`@@ -114,8 +114,11 @@ public override object GetPattern(PatternInterface patternInterface)`
`114`	`114`	`return this;`
`115`	`115`	`if (patternInterface == PatternInterface.Scroll) {`
`116`	`116`	`TextEditor editor = TextArea.GetService(typeof(TextEditor)) as TextEditor;`
`117`		`- if (editor != null)`
`118`		`- return FromElement(editor).GetPattern(patternInterface);`
	`117`	`+ if (editor != null) {`
	`118`	`+ var fromElement = FromElement(editor);`
	`119`	`+ if (fromElement != null)`
	`120`	`+ fromElement.GetPattern(patternInterface);`
	`121`	`+ }`
`119`	`122`	`}`
`120`	`123`	`return base.GetPattern(patternInterface);`
`121`	`124`	`}`