Refactor lua helper script to separate file

And write a few tests for it

processor/luahelper-test.lua

@@ -0,0 +1,94 @@
+-- Load the helper script
+dofile("luahelper.lua")
+
+-- Test helper function
+local function assert(condition, message)
+	if not condition then error("ASSERTION FAILED: " .. (message or "unknown error")) end
+end
+
+local function test(name, fn)
+	local ok, err = pcall(fn)
+	if ok then
+		print("PASS: " .. name)
+	else
+		print("FAIL: " .. name .. " - " .. tostring(err))
+	end
+end
+
+-- Test fromCSV basic parsing
+test("fromCSV basic", function()
+	local csv = "a,b,c\n1,2,3\n4,5,6"
+	local rows = fromCSV(csv)
+	assert(#rows == 3, "Should have 3 rows")
+	assert(rows[1][1] == "a", "First row first field should be 'a'")
+	assert(rows[2][2] == "2", "Second row second field should be '2'")
+end)
+
+-- Test fromCSV with headers
+test("fromCSV with headers", function()
+	local csv = "foo,bar,baz\n1,2,3\n4,5,6"
+	local rows = fromCSV(csv, ",", true)
+	assert(#rows == 2, "Should have 2 data rows")
+	assert(rows[1][1] == "1", "First row first field should be '1'")
+	assert(rows[1].foo == "1", "First row foo should be '1'")
+	assert(rows[1].bar == "2", "First row bar should be '2'")
+	assert(rows[1].baz == "3", "First row baz should be '3'")
+end)
+
+-- Test fromCSV with custom delimiter
+test("fromCSV with tab delimiter", function()
+	local csv = "a\tb\tc\n1\t2\t3"
+	local rows = fromCSV(csv, "\t")
+	assert(#rows == 2, "Should have 2 rows")
+	assert(rows[1][1] == "a", "First row first field should be 'a'")
+	assert(rows[2][2] == "2", "Second row second field should be '2'")
+end)
+
+-- Test fromCSV with quoted fields
+test("fromCSV with quoted fields", function()
+	local csv = '"hello,world","test"\n"foo","bar"'
+	local rows = fromCSV(csv)
+	assert(#rows == 2, "Should have 2 rows")
+	assert(rows[1][1] == "hello,world", "Quoted field with comma should be preserved")
+	assert(rows[1][2] == "test", "Second field should be 'test'")
+end)
+
+-- Test toCSV basic
+test("toCSV basic", function()
+	local rows = { { "a", "b", "c" }, { "1", "2", "3" } }
+	local csv = toCSV(rows)
+	assert(csv == "a,b,c\n1,2,3", "CSV output should match expected")
+end)
+
+-- Test toCSV with custom delimiter
+test("toCSV with tab delimiter", function()
+	local rows = { { "a", "b", "c" }, { "1", "2", "3" } }
+	local csv = toCSV(rows, "\t")
+	assert(csv == "a\tb\tc\n1\t2\t3", "TSV output should match expected")
+end)
+
+-- Test toCSV with fields needing quoting
+test("toCSV with quoted fields", function()
+	local rows = { { "hello,world", "test" }, { "foo", "bar" } }
+	local csv = toCSV(rows)
+	assert(csv == '"hello,world",test\nfoo,bar', "Fields with commas should be quoted")
+end)
+
+-- Test round trip
+test("fromCSV toCSV round trip", function()
+	local original = "a,b,c\n1,2,3\n4,5,6"
+	local rows = fromCSV(original)
+	local csv = toCSV(rows)
+	assert(csv == original, "Round trip should preserve original")
+end)
+
+-- Test round trip with headers
+test("fromCSV toCSV round trip with headers", function()
+	local original = "foo,bar,baz\n1,2,3\n4,5,6"
+	local rows = fromCSV(original, ",", true)
+	local csv = toCSV(rows)
+	local expected = "1,2,3\n4,5,6"
+	assert(csv == expected, "Round trip with headers should preserve data rows")
+end)
+
+print("\nAll tests completed!")