From da0ed94488262cb0cdd958c9aafe5ec2f055304d Mon Sep 17 00:00:00 2001
From: James Allen <james@sharelatex.com>
Date: Tue, 8 Apr 2014 10:51:22 +0100
Subject: [PATCH] Make inconsistency check more reliable and less likely to
 trigger a false positive

---
 .../web/public/coffee/editor/Document.coffee  | 19 +++++++++++++++----
 .../coffee/ide/SavingAreaManager.coffee       |  4 +++-
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/services/web/public/coffee/editor/Document.coffee b/services/web/public/coffee/editor/Document.coffee
index 62987c07e5..b477d41422 100644
--- a/services/web/public/coffee/editor/Document.coffee
+++ b/services/web/public/coffee/editor/Document.coffee
@@ -20,6 +20,7 @@ define [
 			@joined = false
 			@wantToBeJoined = false
 			@_checkConsistency = _.bind(@_checkConsistency, @)
+			@inconsistentCount = 0
 			@_bindToEditorEvents()
 			@_bindToSocketEvents()
 
@@ -34,10 +35,20 @@ define [
 			editorDoc?.off "change", @_checkConsistency
 
 		_checkConsistency: () ->
-			editorValue = @ace?.getValue()
-			sharejsValue = @doc?.getSnapshot()
-			if editorValue != sharejsValue
-				@_onError "error", new Error("Editor text does not match server text")
+			# We've been seeing a lot of errors when I think there shouldn't be
+			# any, which may be related to this check happening before the change is
+			# applied. If we use a timeout, hopefully we can reduce this.
+			setTimeout () =>
+				editorValue = @ace?.getValue()
+				sharejsValue = @doc?.getSnapshot()
+				if editorValue != sharejsValue
+					@inconsistentCount++
+				else
+					@inconsistentCount = 0
+
+				if @inconsistentCount >= 3
+					@_onError new Error("Editor text does not match server text")
+			, 0
 
 		getSnapshot: () ->
 			@doc?.getSnapshot()
diff --git a/services/web/public/coffee/ide/SavingAreaManager.coffee b/services/web/public/coffee/ide/SavingAreaManager.coffee
index 9006eced0a..285995a3ef 100644
--- a/services/web/public/coffee/ide/SavingAreaManager.coffee
+++ b/services/web/public/coffee/ide/SavingAreaManager.coffee
@@ -13,7 +13,9 @@ define [
 				@warnAboutUnsavedChanges()
 
 		pollSavedStatus: () ->
-			saved = @ide.editor.document.pollSavedStatus()
+			doc = @ide.editor.document
+			return if !doc?
+			saved = doc.pollSavedStatus()
 			if saved
 				@unsavedSeconds = 0
 			else