diff --git a/packages/gis/lua/Layer.lua b/packages/gis/lua/Layer.lua
index d60407a5..1e624b0d 100644
--- a/packages/gis/lua/Layer.lua
+++ b/packages/gis/lua/Layer.lua
@@ -1429,11 +1429,15 @@ metaTableLayer_ = {
 function Layer(data)
 	verifyNamedTable(data)
 	mandatoryTableArgument(data, "name", "string")
-	if type(data.project) == "string" then
+
+	local pType = type(data.project)
+
+	if pType == "string" then
 		data.project = File(data.project)
+		pType = "File"
 	end
 
-	if type(data.project) == "File" then
+	if pType == "File" then
 		if not data.project:exists() then
 			customError("Project file '"..data.project.."' does not exist.")
 		end
@@ -1441,6 +1445,8 @@ function Layer(data)
 		data.project = Project{
 			file = data.project
 		}
+	elseif pType ~= "Project" then
+		mandatoryTableArgument(data, "project", "Project")
 	end
 
 	if data.file and type(data.file) == "string" then
diff --git a/packages/gis/lua/TerraLib.lua b/packages/gis/lua/TerraLib.lua
index 3b3223cc..ff496b20 100644
--- a/packages/gis/lua/TerraLib.lua
+++ b/packages/gis/lua/TerraLib.lua
@@ -592,7 +592,7 @@ local function createCellSpaceLayer(inputLayer, name, dSetName, resolution, conn
 												inputLayer:getExtent(), inputLayer:getSRID(), cLType)
 	end
 
-	if errorMsg ~= "" then
+	if errorMsg and errorMsg ~= "" then
 		if type == "POSTGIS" then
 			customError(getPgErrorMessage({layer = inputLayer:getTitle()}, errorMsg))
 		end
diff --git a/packages/gis/tests/functional/alternative/Layer.lua b/packages/gis/tests/functional/alternative/Layer.lua
index c063b26c..b425efaf 100644
--- a/packages/gis/tests/functional/alternative/Layer.lua
+++ b/packages/gis/tests/functional/alternative/Layer.lua
@@ -38,6 +38,12 @@ return{
 
 		unitTest:assertError(projNotExists, "Project file '"..File("myproj.tview").."' does not exist.")
 
+		local noProj = function()
+			Layer{file = "myfile.shp", name = "name"}
+		end
+
+		unitTest:assertError(noProj, mandatoryArgumentMsg("project"))
+
 		local projFile = File("proj_celllayer.tview")
 
 		projFile:deleteIfExists()