[Ide] Check for null filename prior to obtaining GetLastWriteTimeUtc()

New, non-saved, files could have a null filename if the user cancelled the SaveAs operation, ie. the file is still unsaved.

1 files changed, 3 insertions, 1 deletions

diff --git a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Gui/Document.cs b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Gui/Document.cs
index 98b9bedc31..069845ada8 100644
--- a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Gui/Document.cs
+++ b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Gui/Document.cs
@@ -381,7 +381,9 @@ namespace MonoDevelop.Ide.Gui
 				if (doc != null && doc.ParsedFile != null) {
 					string fileName = Window.ViewContent.ContentName;
 					try {
-						doc.ParsedFile.LastWriteTime = File.GetLastWriteTimeUtc (fileName);
+						// filename could be null if the user cancelled SaveAs and this is a new & unsaved file
+						if (fileName != null)
+							doc.ParsedFile.LastWriteTime = File.GetLastWriteTimeUtc (fileName);
 					} catch (Exception e) {
 						doc.ParsedFile.LastWriteTime = DateTime.UtcNow;
 						LoggingService.LogWarning ("Exception while getting the write time from " + fileName, e);