Fix sorting with custom comparator, and add unit tests to regress

src/test/res/sort.lua

@@ -0,0 +1,27 @@
+-- concat
+print( '-- sort tests' )
+local function tryall(cmp)
+	local function try(t)
+		print( table.concat(t,'-') )
+		if pcall( table.sort, t, cmp ) then
+			print( table.concat(t,'-') )
+		else
+			print( 'sort failed' )
+		end
+	end
+	try{ 2, 4, 6, 8, 1, 3, 5, 7 }
+	try{ 333, 222, 111 }
+	try{ "www", "xxx", "yyy", "aaa", "bbb", "ccc" }
+	try{ 21, 23, "25", 27, 22, "24", 26, 28 }
+end
+local function comparator(a,b)
+	return tonumber(a)<tonumber(b) 
+end
+tryall()
+tryall(comparator)
+
+
+
+
+
+