Remove the error return value and instead just throw error

go.mod

@@ -12,7 +12,6 @@ require (
 )
 
 require (
-	github.com/BurntSushi/toml v1.5.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/hexops/valast v1.5.0 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
@@ -22,7 +21,6 @@ require (
 	github.com/mattn/go-sqlite3 v1.14.22 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/rogpeppe/go-internal v1.14.1 // indirect
-	github.com/spf13/cobra v1.10.1 // indirect
 	github.com/spf13/pflag v1.0.9 // indirect
 	github.com/tidwall/match v1.1.1 // indirect
 	github.com/tidwall/pretty v1.2.0 // indirect
@@ -35,7 +33,9 @@ require (
 )
 
 require (
+	github.com/BurntSushi/toml v1.5.0
 	github.com/google/go-cmp v0.6.0
+	github.com/spf13/cobra v1.10.1
 	github.com/tidwall/gjson v1.18.0
 	gorm.io/driver/sqlite v1.6.0
 )

isolate_test.go

@@ -85,7 +85,7 @@ END`
 
 	// Run the isolate commands
 	result, err := RunIsolateCommands(association, "test.txt", testContent, false)
-	if err != nil && err != NothingToDo {
+	if err != nil && err != ErrNothingToDo {
 		t.Fatalf("Failed to run isolate commands: %v", err)
 	}
 
@@ -163,7 +163,7 @@ END_SECTION2`
 
 	// Run the isolate commands
 	result, err := RunIsolateCommands(associations["test.txt"], "test.txt", testContent, false)
-	if err != nil && err != NothingToDo {
+	if err != nil && err != ErrNothingToDo {
 		t.Fatalf("Failed to run isolate commands: %v", err)
 	}
 
@@ -235,7 +235,7 @@ func TestIsolateCommandsWithJSONMode(t *testing.T) {
 
 	// Run the isolate commands
 	result, err := RunIsolateCommands(associations["test.json"], "test.json", testContent, false)
-	if err != nil && err != NothingToDo {
+	if err != nil && err != ErrNothingToDo {
 		t.Fatalf("Failed to run isolate commands: %v", err)
 	}
 
@@ -310,7 +310,7 @@ END_REGULAR`
 
 	// First run isolate commands
 	isolateResult, err := RunIsolateCommands(association, "test.txt", testContent, false)
-	if err != nil && err != NothingToDo {
+	if err != nil && err != ErrNothingToDo {
 		t.Fatalf("Failed to run isolate commands: %v", err)
 	}
 
@@ -321,7 +321,7 @@ END_REGULAR`
 	// Then run regular commands
 	commandLoggers := make(map[string]*logger.Logger)
 	finalResult, err := RunOtherCommands("test.txt", isolateResult, association, commandLoggers, false)
-	if err != nil && err != NothingToDo {
+	if err != nil && err != ErrNothingToDo {
 		t.Fatalf("Failed to run regular commands: %v", err)
 	}
 
@@ -364,12 +364,12 @@ irons_spellbooks:chain_lightning
 	// Second command: targets all SpellPowerMultiplier with multiplier *4
 	commands := []utils.ModifyCommand{
 		{
-			Name:    "healing",
+			Name: "healing",
 			Regexes: []string{
 				`irons_spellbooks:chain_creeper[\s\S]*?SpellPowerMultiplier = !num`,
 				`irons_spellbooks:chain_lightning[\s\S]*?SpellPowerMultiplier = !num`,
 			},
-			Lua:     `v1 * 4`,  // This should multiply by 4
+			Lua:     `v1 * 4`, // This should multiply by 4
 			Files:   []string{"irons_spellbooks-server.toml"},
 			Reset:   true,
 			Isolate: true,
@@ -377,7 +377,7 @@ irons_spellbooks:chain_lightning
 		{
 			Name:    "spellpower",
 			Regex:   `SpellPowerMultiplier = !num`,
-			Lua:     `v1 * 4`,  // This should multiply by 4 again
+			Lua:     `v1 * 4`, // This should multiply by 4 again
 			Files:   []string{"irons_spellbooks-server.toml"},
 			Reset:   true,
 			Isolate: true,
@@ -398,7 +398,7 @@ irons_spellbooks:chain_lightning
 
 	// Run the isolate commands
 	result, err := RunIsolateCommands(association, "irons_spellbooks-server.toml", testContent, false)
-	if err != nil && err != NothingToDo {
+	if err != nil && err != ErrNothingToDo {
 		t.Fatalf("Failed to run isolate commands: %v", err)
 	}
 
@@ -414,4 +414,4 @@ irons_spellbooks:chain_lightning
 
 	t.Logf("Original content:\n%s\n", testContent)
 	t.Logf("Result content:\n%s\n", result)
-}
+}

main.go

@@ -340,23 +340,23 @@ func runModifier(args []string, cmd *cobra.Command) {
 			isChanged := false
 			mainLogger.Debug("Running isolate commands for file %q", file)
 			fileDataStr, err = RunIsolateCommands(association, file, fileDataStr, jsonFlag)
-			if err != nil && err != NothingToDo {
+			if err != nil && err != ErrNothingToDo {
 				mainLogger.Error("Failed to run isolate commands for file %q: %v", file, err)
 				atomic.AddInt64(&stats.FailedFiles, 1)
 				return
 			}
-			if err != NothingToDo {
+			if err != ErrNothingToDo {
 				isChanged = true
 			}
 
 			mainLogger.Debug("Running other commands for file %q", file)
 			fileDataStr, err = RunOtherCommands(file, fileDataStr, association, commandLoggers, jsonFlag)
-			if err != nil && err != NothingToDo {
+			if err != nil && err != ErrNothingToDo {
 				mainLogger.Error("Failed to run other commands for file %q: %v", file, err)
 				atomic.AddInt64(&stats.FailedFiles, 1)
 				return
 			}
-			if err != NothingToDo {
+			if err != ErrNothingToDo {
 				isChanged = true
 			}
 
@@ -474,7 +474,7 @@ func CreateExampleConfig() {
 	createExampleConfigLogger.Info("Wrote example_cook.toml")
 }
 
-var NothingToDo = errors.New("nothing to do")
+var ErrNothingToDo = errors.New("nothing to do")
 
 func RunOtherCommands(file string, fileDataStr string, association utils.FileCommandAssociation, commandLoggers map[string]*logger.Logger, jsonFlag bool) (string, error) {
 	runOtherCommandsLogger := mainLogger.WithPrefix("RunOtherCommands").WithField("file", file)
@@ -565,7 +565,7 @@ func RunOtherCommands(file string, fileDataStr string, association utils.FileCom
 
 	if len(modifications) == 0 {
 		runOtherCommandsLogger.Warning("No modifications found for file")
-		return fileDataStr, NothingToDo
+		return fileDataStr, ErrNothingToDo
 	}
 	runOtherCommandsLogger.Debug("Executing %d modifications for file", len(modifications))
 
@@ -663,7 +663,7 @@ func RunIsolateCommands(association utils.FileCommandAssociation, file string, f
 	}
 	if !anythingDone {
 		runIsolateCommandsLogger.Debug("No isolate modifications were made for file")
-		return fileDataStr, NothingToDo
+		return fileDataStr, ErrNothingToDo
 	}
 	return currentFileData, nil
 }

processor/json.go

@@ -1,3 +1,5 @@
+// Package processor provides JSON processing and Lua script execution capabilities
+// for data transformation and manipulation.
 package processor
 
 import (
@@ -19,9 +21,9 @@ var jsonLogger = logger.Default.WithPrefix("processor/json")
 
 // ProcessJSON applies Lua processing to JSON content
 func ProcessJSON(content string, command utils.ModifyCommand, filename string) ([]utils.ReplaceCommand, error) {
-	processJsonLogger := jsonLogger.WithPrefix("ProcessJSON").WithField("commandName", command.Name).WithField("file", filename)
-	processJsonLogger.Debug("Starting JSON processing for file")
-	processJsonLogger.Trace("Initial file content length: %d", len(content))
+	processJSONLogger := jsonLogger.WithPrefix("ProcessJSON").WithField("commandName", command.Name).WithField("file", filename)
+	processJSONLogger.Debug("Starting JSON processing for file")
+	processJSONLogger.Trace("Initial file content length: %d", len(content))
 
 	var commands []utils.ReplaceCommand
 	startTime := time.Now()
@@ -30,15 +32,15 @@ func ProcessJSON(content string, command utils.ModifyCommand, filename string) (
 	var jsonData interface{}
 	err := json.Unmarshal([]byte(content), &jsonData)
 	if err != nil {
-		processJsonLogger.Error("Failed to parse JSON content: %v", err)
+		processJSONLogger.Error("Failed to parse JSON content: %v", err)
 		return commands, fmt.Errorf("failed to parse JSON: %v", err)
 	}
-	processJsonLogger.Debug("Successfully parsed JSON content")
+	processJSONLogger.Debug("Successfully parsed JSON content")
 
 	// Create Lua state
 	L, err := NewLuaState()
 	if err != nil {
-		processJsonLogger.Error("Error creating Lua state: %v", err)
+		processJSONLogger.Error("Error creating Lua state: %v", err)
 		return commands, fmt.Errorf("error creating Lua state: %v", err)
 	}
 	defer L.Close()
@@ -49,70 +51,58 @@ func ProcessJSON(content string, command utils.ModifyCommand, filename string) (
 	// Convert JSON data to Lua table
 	luaTable, err := ToLuaTable(L, jsonData)
 	if err != nil {
-		processJsonLogger.Error("Failed to convert JSON to Lua table: %v", err)
+		processJSONLogger.Error("Failed to convert JSON to Lua table: %v", err)
 		return commands, fmt.Errorf("failed to convert JSON to Lua table: %v", err)
 	}
 
 	// Set the JSON data as a global variable
 	L.SetGlobal("data", luaTable)
-	processJsonLogger.Debug("Set JSON data as Lua global 'data'")
+	processJSONLogger.Debug("Set JSON data as Lua global 'data'")
 
 	// Build and execute Lua script for JSON mode
 	luaExpr := BuildJSONLuaScript(command.Lua)
-	processJsonLogger.Debug("Built Lua script from expression: %q", command.Lua)
-	processJsonLogger.Trace("Full Lua script: %q", utils.LimitString(luaExpr, 200))
+	processJSONLogger.Debug("Built Lua script from expression: %q", command.Lua)
+	processJSONLogger.Trace("Full Lua script: %q", utils.LimitString(luaExpr, 200))
 
 	if err := L.DoString(luaExpr); err != nil {
-		processJsonLogger.Error("Lua script execution failed: %v\nScript: %s", err, utils.LimitString(luaExpr, 200))
+		processJSONLogger.Error("Lua script execution failed: %v\nScript: %s", err, utils.LimitString(luaExpr, 200))
 		return commands, fmt.Errorf("lua script execution failed: %v", err)
 	}
-	processJsonLogger.Debug("Lua script executed successfully")
+	processJSONLogger.Debug("Lua script executed successfully")
 
 	// Check if modification flag is set
 	modifiedVal := L.GetGlobal("modified")
 	if modifiedVal.Type() != lua.LTBool || !lua.LVAsBool(modifiedVal) {
-		processJsonLogger.Debug("Skipping - no modifications indicated by Lua script")
+		processJSONLogger.Debug("Skipping - no modifications indicated by Lua script")
 		return commands, nil
 	}
 
 	// Get the modified data from Lua
 	modifiedData := L.GetGlobal("data")
 	if modifiedData.Type() != lua.LTTable {
-		processJsonLogger.Error("Expected 'data' to be a table after Lua processing, got %s", modifiedData.Type().String())
+		processJSONLogger.Error("Expected 'data' to be a table after Lua processing, got %s", modifiedData.Type().String())
 		return commands, fmt.Errorf("expected 'data' to be a table after Lua processing")
 	}
 
 	// Convert back to Go interface
 	goData, err := FromLua(L, modifiedData)
 	if err != nil {
-		processJsonLogger.Error("Failed to convert Lua table back to Go: %v", err)
+		processJSONLogger.Error("Failed to convert Lua table back to Go: %v", err)
 		return commands, fmt.Errorf("failed to convert Lua table back to Go: %v", err)
 	}
 
-	processJsonLogger.Debug("About to call applyChanges with original data and modified data")
+	processJSONLogger.Debug("About to call applyChanges with original data and modified data")
 	commands, err = applyChanges(content, jsonData, goData)
 	if err != nil {
-		processJsonLogger.Error("Failed to apply surgical JSON changes: %v", err)
+		processJSONLogger.Error("Failed to apply surgical JSON changes: %v", err)
 		return commands, fmt.Errorf("failed to apply surgical JSON changes: %v", err)
 	}
 
-	processJsonLogger.Debug("Total JSON processing time: %v", time.Since(startTime))
-	processJsonLogger.Debug("Generated %d total modifications", len(commands))
+	processJSONLogger.Debug("Total JSON processing time: %v", time.Since(startTime))
+	processJSONLogger.Debug("Generated %d total modifications", len(commands))
 	return commands, nil
 }
 
-// applyJSONChanges compares original and modified data and applies changes surgically
-func applyJSONChanges(content string, originalData, modifiedData interface{}) ([]utils.ReplaceCommand, error) {
-	var commands []utils.ReplaceCommand
-
-	appliedCommands, err := applyChanges(content, originalData, modifiedData)
-	if err == nil && len(appliedCommands) > 0 {
-		return appliedCommands, nil
-	}
-
-	return commands, fmt.Errorf("failed to make any changes to the json")
-}
-
 // applyChanges attempts to make surgical changes while preserving exact formatting
 func applyChanges(content string, originalData, modifiedData interface{}) ([]utils.ReplaceCommand, error) {
 	var commands []utils.ReplaceCommand
@@ -199,12 +189,10 @@ func applyChanges(content string, originalData, modifiedData interface{}) ([]uti
 
 		// Convert the new value to JSON string
 		newValueStr := convertValueToJSONString(newValue)
-		
-		
+
 		// Insert the new field with pretty-printed formatting
 		// Format: ,"fieldName": { ... }
 		insertText := fmt.Sprintf(`,"%s": %s`, fieldName, newValueStr)
-		
 
 		commands = append(commands, utils.ReplaceCommand{
 			From: startPos,
@@ -437,8 +425,6 @@ func findDeepChanges(basePath string, original, modified interface{}) map[string
 						}
 						changes[currentPath] = nil // Mark for removal
 					}
-				} else {
-					// Elements added - more complex, skip for now
 				}
 			} else {
 				// Same length - check individual elements for value changes

processor/luahelper-test-regress.lua

@@ -0,0 +1,43 @@
+-- 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("regression test 001", function()
+	local csv =
+		[[Id	Enabled	ModuleId	DepartmentId	IsDepartment	PositionInGraph	Parents	Modifiers	UpgradePrice
+news_department	TRUE	navigation		TRUE	2 0		NewsAnalyticsDepartment + 1	communication_relay communication_relay
+nd_charge_bonus	TRUE	navigation	news_department	FALSE	1 0	news_department	NDSkillChargeBonus + 1	expert_disk expert_disk
+nd_cooldown_time_reduce	TRUE	navigation	news_department	FALSE	3 0	news_department	NDCooldownTimeReduce - 2	communication_relay communication_relay]]
+	local rows, err = fromCSV(csv, { delimiter = "\t", hasheader = true, hascomments = true })
+	if err then error("fromCSV error: " .. err) end
+	assert(#rows == 3, "Should have 3 rows")
+	assert(rows[1].Id == "news_department", "First row Id should be 'news_department'")
+	assert(rows[1].Enabled == "TRUE", "First row Enabled should be 'TRUE'")
+	assert(rows[1].ModuleId == "navigation", "First row ModuleId should be 'navigation'")
+	assert(rows[1].DepartmentId == "", "First row DepartmentId should be ''")
+	assert(rows[1].IsDepartment == "TRUE", "First row IsDepartment should be 'TRUE'")
+	assert(rows.Headers[1] == "Id", "First row Headers should be 'Id'")
+	assert(rows.Headers[2] == "Enabled", "First row Headers should be 'Enabled'")
+	assert(rows.Headers[3] == "ModuleId", "First row Headers should be 'ModuleId'")
+	assert(rows.Headers[4] == "DepartmentId", "First row Headers should be 'DepartmentId'")
+	assert(rows.Headers[5] == "IsDepartment", "First row Headers should be 'IsDepartment'")
+	assert(rows.Headers[6] == "PositionInGraph", "First row Headers should be 'PositionInGraph'")
+	assert(rows.Headers[7] == "Parents", "First row Headers should be 'Parents'")
+	assert(rows.Headers[8] == "Modifiers", "First row Headers should be 'Modifiers'")
+	assert(rows.Headers[9] == "UpgradePrice", "First row Headers should be 'UpgradePrice'")
+end)
+
+print("\nAll tests completed!")

processor/luahelper-test.lua

@@ -18,26 +18,23 @@ end
 -- Test fromCSV option validation
 test("fromCSV invalid option", function()
 	local csv = "a,b,c\n1,2,3"
-	local rows, err = fromCSV(csv, { invalidOption = true })
-	assert(rows ~= nil and #rows == 0, "Should return empty table on error")
-	assert(err ~= nil, "Should return error message")
-	assert(string.find(err, "unknown option"), "Error should mention unknown option")
+	local ok, errMsg = pcall(function() fromCSV(csv, { invalidOption = true }) end)
+	assert(ok == false, "Should raise error")
+	assert(string.find(errMsg, "unknown option"), "Error should mention unknown option")
 end)
 
--- Test toCSV error handling
+-- Test toCSV invalid delimiter
 test("toCSV invalid delimiter", function()
 	local rows = { { "a", "b", "c" } }
-	local csv, err = toCSV(rows, { delimiter = 123 })
+	local csv = toCSV(rows, { delimiter = 123 })
 	-- toCSV converts delimiter to string, so 123 becomes "123"
 	assert(csv == "a123b123c", "Should convert delimiter to string")
-	assert(err == nil, "Should not return error")
 end)
 
 -- Test fromCSV basic parsing
 test("fromCSV basic", function()
 	local csv = "a,b,c\n1,2,3\n4,5,6"
-	local rows, err = fromCSV(csv)
-	if err then error("fromCSV error: " .. err) end
+	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'")
@@ -46,8 +43,7 @@ end)
 -- Test fromCSV with headers
 test("fromCSV with headers", function()
 	local csv = "foo,bar,baz\n1,2,3\n4,5,6"
-	local rows, err = fromCSV(csv, { hasheader = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hasheader = 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'")
@@ -58,8 +54,7 @@ end)
 -- Test fromCSV with custom delimiter
 test("fromCSV with tab delimiter", function()
 	local csv = "a\tb\tc\n1\t2\t3"
-	local rows, err = fromCSV(csv, { delimiter = "\t" })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { delimiter = "\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'")
@@ -68,8 +63,7 @@ end)
 -- Test fromCSV with quoted fields
 test("fromCSV with quoted fields", function()
 	local csv = '"hello,world","test"\n"foo","bar"'
-	local rows, err = fromCSV(csv)
-	if err then error("fromCSV error: " .. err) end
+	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'")
@@ -78,44 +72,37 @@ end)
 -- Test toCSV basic
 test("toCSV basic", function()
 	local rows = { { "a", "b", "c" }, { "1", "2", "3" } }
-	local csv, err = toCSV(rows)
-	if err then error("toCSV error: " .. err) end
+	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, err = toCSV(rows, { delimiter = "\t" })
-	if err then error("toCSV error: " .. err) end
+	local csv = toCSV(rows, { delimiter = "\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, err = toCSV(rows)
-	if err then error("toCSV error: " .. err) end
+	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, err = fromCSV(original)
-	if err then error("fromCSV error: " .. err) end
-	local csv, err = toCSV(rows)
-	if err then error("toCSV error: " .. err) end
+	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, err = fromCSV(original, { hasheader = true })
-	if err then error("fromCSV error: " .. err) end
-	local csv, err = toCSV(rows)
-	if err then error("toCSV error: " .. err) end
+	local rows = fromCSV(original, { hasheader = 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)
@@ -123,8 +110,7 @@ end)
 -- Test fromCSV with comments
 test("fromCSV with comments", function()
 	local csv = "# This is a comment\nfoo,bar,baz\n1,2,3\n# Another comment\n4,5,6"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 3, "Should have 3 rows (comments filtered, header + 2 data rows)")
 	assert(rows[1][1] == "foo", "First row should be header row")
 	assert(rows[2][1] == "1", "Second row first field should be '1'")
@@ -134,8 +120,7 @@ end)
 -- Test fromCSV with comments and headers
 test("fromCSV with comments and headers", function()
 	local csv = "#mercenary_profiles\nId,Name,Value\n1,Test,100\n# End of data\n2,Test2,200"
-	local rows, err = fromCSV(csv, { hasheader = true, hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hasheader = true, hascomments = true })
 	assert(#rows == 2, "Should have 2 data rows")
 	assert(rows[1].Id == "1", "First row Id should be '1'")
 	assert(rows[1].Name == "Test", "First row Name should be 'Test'")
@@ -146,8 +131,7 @@ end)
 -- Test fromCSV with comments disabled
 test("fromCSV without comments", function()
 	local csv = "# This should not be filtered\nfoo,bar\n1,2"
-	local rows, err = fromCSV(csv, { hascomments = false })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = false })
 	assert(#rows == 3, "Should have 3 rows (including comment)")
 	assert(rows[1][1] == "# This should not be filtered", "Comment line should be preserved")
 end)
@@ -155,8 +139,7 @@ end)
 -- Test fromCSV with comment at start
 test("fromCSV comment at start", function()
 	local csv = "# Header comment\nId,Name\n1,Test"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 2, "Should have 2 rows (comment filtered)")
 	assert(rows[1][1] == "Id", "First row should be header")
 end)
@@ -164,8 +147,7 @@ end)
 -- Test fromCSV with comment with leading whitespace
 test("fromCSV comment with whitespace", function()
 	local csv = "  # Comment with spaces\nId,Name\n1,Test"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 2, "Should have 2 rows (comment with spaces filtered)")
 	assert(rows[1][1] == "Id", "First row should be header")
 end)
@@ -173,8 +155,7 @@ end)
 -- Test fromCSV with comment with tabs
 test("fromCSV comment with tabs", function()
 	local csv = "\t# Comment with tab\nId,Name\n1,Test"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 2, "Should have 2 rows (comment with tab filtered)")
 	assert(rows[1][1] == "Id", "First row should be header")
 end)
@@ -182,8 +163,7 @@ end)
 -- Test fromCSV with multiple consecutive comments
 test("fromCSV multiple consecutive comments", function()
 	local csv = "# First comment\n# Second comment\n# Third comment\nId,Name\n1,Test"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 2, "Should have 2 rows (all comments filtered)")
 	assert(rows[1][1] == "Id", "First row should be header")
 end)
@@ -191,8 +171,7 @@ end)
 -- Test fromCSV with comment in middle of data
 test("fromCSV comment in middle", function()
 	local csv = "Id,Name\n1,Test\n# Middle comment\n2,Test2"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 3, "Should have 3 rows (comment filtered)")
 	assert(rows[1][1] == "Id", "First row should be header")
 	assert(rows[2][1] == "1", "Second row should be first data")
@@ -202,8 +181,7 @@ end)
 -- Test fromCSV with comment at end
 test("fromCSV comment at end", function()
 	local csv = "Id,Name\n1,Test\n# End comment"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 2, "Should have 2 rows (end comment filtered)")
 	assert(rows[1][1] == "Id", "First row should be header")
 	assert(rows[2][1] == "1", "Second row should be data")
@@ -212,8 +190,7 @@ end)
 -- Test fromCSV with empty comment line
 test("fromCSV empty comment", function()
 	local csv = "#\nId,Name\n1,Test"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 2, "Should have 2 rows (empty comment filtered)")
 	assert(rows[1][1] == "Id", "First row should be header")
 end)
@@ -221,8 +198,7 @@ end)
 -- Test fromCSV with comment and headers
 test("fromCSV comment with headers enabled", function()
 	local csv = "#mercenary_profiles\nId,Name,Value\n1,Test,100\n2,Test2,200"
-	local rows, err = fromCSV(csv, { hasheader = true, hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hasheader = true, hascomments = true })
 	assert(#rows == 2, "Should have 2 data rows")
 	assert(rows[1].Id == "1", "First row Id should be '1'")
 	assert(rows[1].Name == "Test", "First row Name should be 'Test'")
@@ -232,8 +208,7 @@ end)
 -- Test fromCSV with comment and TSV delimiter
 test("fromCSV comment with tab delimiter", function()
 	local csv = "# Comment\nId\tName\n1\tTest"
-	local rows, err = fromCSV(csv, { delimiter = "\t", hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { delimiter = "\t", hascomments = true })
 	assert(#rows == 2, "Should have 2 rows")
 	assert(rows[1][1] == "Id", "First row should be header")
 	assert(rows[2][1] == "1", "Second row first field should be '1'")
@@ -242,8 +217,7 @@ end)
 -- Test fromCSV with comment and headers and TSV
 test("fromCSV comment with headers and TSV", function()
 	local csv = "#mercenary_profiles\nId\tName\tValue\n1\tTest\t100"
-	local rows, err = fromCSV(csv, { delimiter = "\t", hasheader = true, hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { delimiter = "\t", hasheader = true, hascomments = true })
 	assert(#rows == 1, "Should have 1 data row")
 	assert(rows[1].Id == "1", "Row Id should be '1'")
 	assert(rows[1].Name == "Test", "Row Name should be 'Test'")
@@ -253,8 +227,7 @@ end)
 -- Test fromCSV with data field starting with # (not a comment)
 test("fromCSV data field starting with hash", function()
 	local csv = "Id,Name\n1,#NotAComment\n2,Test"
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 3, "Should have 3 rows (data with # not filtered)")
 	assert(rows[1][1] == "Id", "First row should be header")
 	assert(rows[2][2] == "#NotAComment", "Second row should have #NotAComment as data")
@@ -263,8 +236,7 @@ end)
 -- Test fromCSV with quoted field starting with #
 test("fromCSV quoted field with hash", function()
 	local csv = 'Id,Name\n1,"#NotAComment"\n2,Test'
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 3, "Should have 3 rows (quoted # not filtered)")
 	assert(rows[2][2] == "#NotAComment", "Quoted field with # should be preserved")
 end)
@@ -272,8 +244,7 @@ end)
 -- Test fromCSV with comment after quoted field
 test("fromCSV comment after quoted field", function()
 	local csv = 'Id,Name\n1,"Test"\n# This is a comment\n2,Test2'
-	local rows, err = fromCSV(csv, { hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { hascomments = true })
 	assert(#rows == 3, "Should have 3 rows (comment filtered)")
 	assert(rows[2][2] == "Test", "Quoted field should be preserved")
 	assert(rows[3][1] == "2", "Third row should be second data row")
@@ -414,8 +385,7 @@ Id	ModifyStartCost	ModifyStep	ModifyLevelLimit	Health	ResistSheet	WoundSlots	Mel
 john_hawkwood_boss	20	0.1		140	blunt 0 pierce 0 lacer 0 fire 0 cold 0 poison 0 shock 0 beam 0	HumanHead HumanShoulder HumanArm HumanThigh HumanFeet HumanChest HumanBody HumanStomach HumanKnee	blunt 8 16 crit 1.60 critchance 0.05	0.5	0.5	0.03	0.5	1.2	0.3	8	2200	16	2	talent_the_man_who_sold_the_world	human_male	0	hair1	#633D08	player		Human
 francis_reid_daly	20	0.1		130	blunt 0 pierce 0 lacer 0 fire 0 cold 0 poison 0 shock 0 beam 0	HumanHead HumanShoulder HumanArm HumanThigh HumanFeet HumanChest HumanBody HumanStomach HumanKnee	blunt 7 14 crit 1.70 critchance 0.05	0.5	0.4	0.04	0.9	1	0.3	8	2000	10	1	talent_weapon_durability	human_male	0			player		Human
 ]]
-	local rows, err = fromCSV(teststr, { delimiter = "\t", hasheader = true, hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(teststr, { delimiter = "\t", hasheader = true, hascomments = true })
 	assert(#rows == 2, "Should have 2 data rows")
 
 	-- Test first row
@@ -440,8 +410,7 @@ end)
 
 test("fromCSV debug header assignment", function()
 	local csv = "Id	Name	Value\n1	Test	100\n2	Test2	200"
-	local rows, err = fromCSV(csv, { delimiter = "\t", hasheader = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { delimiter = "\t", hasheader = true })
 	assert(rows[1].Id == "1", "Id should be '1'")
 	assert(rows[1].Name == "Test", "Name should be 'Test'")
 	assert(rows[1].Value == "100", "Value should be '100'")
@@ -453,8 +422,7 @@ Id	ModifyStartCost	ModifyStep	ModifyLevelLimit	Health	ResistSheet	WoundSlots	Mel
 john_hawkwood_boss	20	0.1		140	blunt 0 pierce 0 lacer 0 fire 0 cold 0 poison 0 shock 0 beam 0	HumanHead HumanShoulder HumanArm HumanThigh HumanFeet HumanChest HumanBody HumanStomach HumanKnee	blunt 8 16 crit 1.60 critchance 0.05	0.5	0.5	0.03	0.5	1.2	0.3	8	2200	16	2	talent_the_man_who_sold_the_world	human_male	0	hair1	#633D08	player		Human
 francis_reid_daly	20	0.1		130	blunt 0 pierce 0 lacer 0 fire 0 cold 0 poison 0 shock 0 beam 0	HumanHead HumanShoulder HumanArm HumanThigh HumanFeet HumanChest HumanBody HumanStomach HumanKnee	blunt 7 14 crit 1.70 critchance 0.05	0.5	0.4	0.04	0.9	1	0.3	8	2000	10	1	talent_weapon_durability	human_male	0			player		Human
 ]]
-	local rows, err = fromCSV(csv, { delimiter = "\t", hasheader = true, hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(csv, { delimiter = "\t", hasheader = true, hascomments = true })
 	assert(#rows == 2, "Should have 2 data rows")
 
 	assert(rows[1].Id == "john_hawkwood_boss", "First row Id should be 'john_hawkwood_boss'")
@@ -491,17 +459,14 @@ phoenix_brigade	30	0.1	shielding_basic battle_physicist_basic reinforced_battery
 ]]
 
 	-- Parse with headers and comments
-	local rows, err = fromCSV(original, { delimiter = "\t", hasheader = true, hascomments = true })
-	if err then error("fromCSV error: " .. err) end
+	local rows = fromCSV(original, { delimiter = "\t", hasheader = true, hascomments = true })
 	assert(#rows > 0, "Should have parsed rows")
 
 	-- Convert back to CSV with headers
-	local csv, err = toCSV(rows, { delimiter = "\t", hasheader = true })
-	if err then error("toCSV error: " .. err) end
+	local csv = toCSV(rows, { delimiter = "\t", hasheader = true })
 
 	-- Parse again
-	local rows2, err = fromCSV(csv, { delimiter = "\t", hasheader = true, hascomments = false })
-	if err then error("fromCSV error: " .. err) end
+	local rows2 = fromCSV(csv, { delimiter = "\t", hasheader = true, hascomments = false })
 
 	-- Verify identical - same number of rows
 	assert(#rows2 == #rows, "Round trip should have same number of rows")
@@ -515,9 +480,55 @@ phoenix_brigade	30	0.1	shielding_basic battle_physicist_basic reinforced_battery
 	assert(rows2[1].Health == rows[1].Health, "Round trip first row Health should match")
 
 	-- Verify headers are preserved
-	assert(rows2[1].Headers ~= nil, "Round trip rows should have Headers field")
-	assert(#rows2[1].Headers == #rows[1].Headers, "Headers should have same number of elements")
-	assert(rows2[1].Headers[1] == rows[1].Headers[1], "First header should match")
+	assert(rows2.Headers ~= nil, "Round trip rows should have Headers field")
+	assert(#rows2.Headers == #rows.Headers, "Headers should have same number of elements")
+	assert(rows2.Headers[1] == rows.Headers[1], "First header should match")
+end)
+
+-- Test metatable: row[1] and row.foobar return same value
+test("metatable row[1] equals row.header", function()
+	local csv = "Id	Name	Value\n1	Test	100"
+	local rows = fromCSV(csv, { delimiter = "\t", hasheader = true })
+	assert(rows[1][1] == rows[1].Id, "row[1] should equal row.Id")
+	assert(rows[1][2] == rows[1].Name, "row[2] should equal row.Name")
+	assert(rows[1][3] == rows[1].Value, "row[3] should equal row.Value")
+	assert(rows[1].Id == "1", "row.Id should be '1'")
+	assert(rows[1][1] == "1", "row[1] should be '1'")
+end)
+
+-- Test metatable: setting via header name updates numeric index
+test("metatable set via header name", function()
+	local csv = "Id	Name	Value\n1	Test	100"
+	local rows = fromCSV(csv, { delimiter = "\t", hasheader = true })
+	rows[1].Id = "999"
+	assert(rows[1][1] == "999", "Setting row.Id should update row[1]")
+	assert(rows[1].Id == "999", "row.Id should be '999'")
+end)
+
+-- Test metatable: error on unknown header assignment
+test("metatable error on unknown header", function()
+	local csv = "Id	Name	Value\n1	Test	100"
+	local rows = fromCSV(csv, { delimiter = "\t", hasheader = true })
+	local ok, errMsg = pcall(function() rows[1].UnknownHeader = "test" end)
+	assert(ok == false, "Should error on unknown header")
+	assert(string.find(errMsg, "unknown header"), "Error should mention unknown header")
+end)
+
+-- Test metatable: numeric indices still work
+test("metatable numeric indices work", function()
+	local csv = "Id	Name	Value\n1	Test	100"
+	local rows = fromCSV(csv, { delimiter = "\t", hasheader = true })
+	rows[1][1] = "999"
+	assert(rows[1].Id == "999", "Setting row[1] should update row.Id")
+	assert(rows[1][1] == "999", "row[1] should be '999'")
+end)
+
+-- Test metatable: numeric keys work normally
+test("metatable numeric keys work", function()
+	local csv = "Id	Name	Value\n1	Test	100"
+	local rows = fromCSV(csv, { delimiter = "\t", hasheader = true })
+	rows[1][100] = "hundred"
+	assert(rows[1][100] == "hundred", "Numeric keys should work")
 end)
 
 print("\nAll tests completed!")

processor/luahelper.lua

@@ -58,12 +58,10 @@ parserDefaultOptions = { delimiter = ",", hasheader = false, hascomments = false
 
 --- Validates options against a set of valid option keys.
 --- @param options ParserOptions? The options table to validate
---- @return boolean #True if options are valid
---- @return string? #Error message if invalid, nil if valid
 function areOptionsValid(options)
-	if options == nil then return true, nil end
+	if options == nil then return end
 
-	if type(options) ~= "table" then return false, "options must be a table" end
+	if type(options) ~= "table" then error("options must be a table") end
 
 	-- Build valid options list from validOptions table
 	local validOptionsStr = ""
@@ -73,12 +71,11 @@ function areOptionsValid(options)
 
 	for k, _ in pairs(options) do
 		if parserDefaultOptions[k] == nil then
-			return false,
+			error(
 				"unknown option: " .. tostring(k) .. " (valid options: " .. validOptionsStr .. ")"
+			)
 		end
 	end
-
-	return true, nil
 end
 
 --- Parses CSV text into rows and fields using a minimal RFC 4180 state machine.
@@ -99,13 +96,11 @@ end
 --- @param csv string The CSV text to parse.
 --- @param options ParserOptions? Options for the parser
 --- @return table #A table (array) of rows; each row is a table with numeric indices and optionally header-named keys.
---- @return string? #Error message if parsing fails.
 function fromCSV(csv, options)
 	if options == nil then options = {} end
 
 	-- Validate options
-	local isValid, err = areOptionsValid(options)
-	if not isValid then return {}, err end
+	areOptionsValid(options)
 
 	local delimiter = options.delimiter or parserDefaultOptions.delimiter
 	local hasheader = options.hasheader or parserDefaultOptions.hasheader
@@ -209,24 +204,52 @@ function fromCSV(csv, options)
 
 	if hasheader and #allRows > 0 then
 		local headers = allRows[1]
+		local headerMap = {}
+		for j = 1, #headers do
+			if headers[j] ~= nil and headers[j] ~= "" then
+				local headerName = trim(headers[j])
+				headerMap[headerName] = j
+			end
+		end
+
+		local header_mt = {
+			headers = headerMap,
+			__index = function(t, key)
+				local mt = getmetatable(t)
+				if type(key) == "string" and mt.headers and mt.headers[key] then
+					return rawget(t, mt.headers[key])
+				end
+				return rawget(t, key)
+			end,
+			__newindex = function(t, key, value)
+				local mt = getmetatable(t)
+				if type(key) == "string" and mt.headers then
+					if mt.headers[key] then
+						rawset(t, mt.headers[key], value)
+					else
+						error("unknown header: " .. tostring(key))
+					end
+				else
+					rawset(t, key, value)
+				end
+			end,
+		}
+
 		local rows = {}
 		for ii = 2, #allRows do
 			local row = {}
 			local dataRow = allRows[ii]
 			for j = 1, #dataRow do
 				row[j] = dataRow[j]
-				if headers[j] ~= nil and headers[j] ~= "" then
-					local headerName = trim(headers[j])
-					row[headerName] = dataRow[j]
-				end
 			end
-			row.Headers = headers
+			setmetatable(row, header_mt)
 			table.insert(rows, row)
 		end
-		return rows, nil
+		rows.Headers = headers
+		return rows
 	end
 
-	return allRows, nil
+	return allRows
 end
 
 --- Converts a table of rows back to CSV text format (RFC 4180 compliant).
@@ -241,23 +264,21 @@ end
 ---
 --- @param rows table Array of rows, where each row is an array of field values.
 --- @param options ParserOptions? Options for the parser
---- @return string? #CSV-formatted text, error string?
---- @return string? #Error message if conversion fails.
+--- @return string #CSV-formatted text
 function toCSV(rows, options)
 	if options == nil then options = {} end
 
 	-- Validate options
-	local isValid, err = areOptionsValid(options)
-	if not isValid then return nil, err end
+	areOptionsValid(options)
 
 	local delimiter = options.delimiter or parserDefaultOptions.delimiter
 	local includeHeaders = options.hasheader or parserDefaultOptions.hasheader
 	local rowStrings = {}
 
 	-- Include headers row if requested and available
-	if includeHeaders and #rows > 0 and rows[1].Headers ~= nil then
+	if includeHeaders and #rows > 0 and rows.Headers ~= nil then
 		local headerStrings = {}
-		for _, header in ipairs(rows[1].Headers) do
+		for _, header in ipairs(rows.Headers) do
 			local headerStr = tostring(header)
 			local needsQuoting = false
 			if
@@ -304,7 +325,7 @@ function toCSV(rows, options)
 		table.insert(rowStrings, table.concat(fieldStrings, delimiter))
 	end
 
-	return table.concat(rowStrings, "\n"), nil
+	return table.concat(rowStrings, "\n")
 end
 
 -- String to number conversion helper

processor/processor.go

@@ -229,8 +229,8 @@ func BuildLuaScript(luaExpr string) string {
 
 // BuildJSONLuaScript prepares a Lua expression for JSON mode
 func BuildJSONLuaScript(luaExpr string) string {
-	buildJsonLuaScriptLogger := processorLogger.WithPrefix("BuildJSONLuaScript").WithField("inputLuaExpr", luaExpr)
-	buildJsonLuaScriptLogger.Debug("Building full Lua script for JSON mode from expression")
+	buildJSONLuaScriptLogger := processorLogger.WithPrefix("BuildJSONLuaScript").WithField("inputLuaExpr", luaExpr)
+	buildJSONLuaScriptLogger.Debug("Building full Lua script for JSON mode from expression")
 
 	// Perform $var substitutions from globalVariables
 	luaExpr = replaceVariables(luaExpr)
@@ -242,7 +242,7 @@ func BuildJSONLuaScript(luaExpr string) string {
 		local res = run()
 		modified = res == nil or res
 	`, luaExpr)
-	buildJsonLuaScriptLogger.Trace("Generated full JSON Lua script: %q", utils.LimitString(fullScript, 200))
+	buildJSONLuaScriptLogger.Trace("Generated full JSON Lua script: %q", utils.LimitString(fullScript, 200))
 
 	return fullScript
 }

processor/regex.go

@@ -22,9 +22,9 @@ type CaptureGroup struct {
 	Range   [2]int
 }
 
-// ProcessContent applies regex replacement with Lua processing
-// The filename here exists ONLY so we can pass it to the lua environment
-// It's not used for anything else
+// ProcessRegex applies regex replacement with Lua processing.
+// The filename here exists ONLY so we can pass it to the lua environment.
+// It's not used for anything else.
 func ProcessRegex(content string, command utils.ModifyCommand, filename string) ([]utils.ReplaceCommand, error) {
 	processRegexLogger := regexLogger.WithPrefix("ProcessRegex").WithField("commandName", command.Name).WithField("file", filename)
 	processRegexLogger.Debug("Starting regex processing for file")
@@ -216,9 +216,6 @@ func ProcessRegex(content string, command utils.ModifyCommand, filename string)
 		}
 
 		if replacement == "" {
-			// Apply the modifications to the original match
-			replacement = matchContent
-
 			// Count groups that were actually modified
 			modifiedGroupsCount := 0
 			for _, capture := range updatedCaptureGroups {

processor/regex_test.go

@@ -30,7 +30,7 @@ func normalizeWhitespace(s string) string {
 	return re.ReplaceAllString(strings.TrimSpace(s), " ")
 }
 
-func ApiAdaptor(content string, regex string, lua string) (string, int, int, error) {
+func APIAdaptor(content string, regex string, lua string) (string, int, int, error) {
 	command := utils.ModifyCommand{
 		Regex:    regex,
 		Lua:      lua,
@@ -79,7 +79,7 @@ func TestSimpleValueMultiplication(t *testing.T) {
     </item>
 </config>`
 
-	result, mods, matches, err := ApiAdaptor(content, `(?s)<value>(\d+)</value>`, "v1 = v1*1.5")
+	result, mods, matches, err := APIAdaptor(content, `(?s)<value>(\d+)</value>`, "v1 = v1*1.5")
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 1, matches, "Expected 1 match, got %d", matches)
@@ -100,7 +100,7 @@ func TestShorthandNotation(t *testing.T) {
     </item>
 </config>`
 
-	result, mods, matches, err := ApiAdaptor(content, `(?s)<value>(\d+)</value>`, "v1*1.5")
+	result, mods, matches, err := APIAdaptor(content, `(?s)<value>(\d+)</value>`, "v1*1.5")
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 1, matches, "Expected 1 match, got %d", matches)
@@ -121,7 +121,7 @@ func TestShorthandNotationFloats(t *testing.T) {
     </item>
 </config>`
 
-	result, mods, matches, err := ApiAdaptor(content, `(?s)<value>(\d+\.\d+)</value>`, "v1*1.5")
+	result, mods, matches, err := APIAdaptor(content, `(?s)<value>(\d+\.\d+)</value>`, "v1*1.5")
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 1, matches, "Expected 1 match, got %d", matches)
@@ -146,7 +146,7 @@ func TestArrayNotation(t *testing.T) {
     </prices>
 </config>`
 
-	result, mods, matches, err := ApiAdaptor(content, `(?s)<price>(\d+)</price>`, "v1*2")
+	result, mods, matches, err := APIAdaptor(content, `(?s)<price>(\d+)</price>`, "v1*2")
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 3, matches, "Expected 3 matches, got %d", matches)
@@ -167,7 +167,7 @@ func TestMultipleNumericMatches(t *testing.T) {
     <entry>400</entry>
 </data>`
 
-	result, mods, matches, err := ApiAdaptor(content, `<entry>(\d+)</entry>`, "v1*2")
+	result, mods, matches, err := APIAdaptor(content, `<entry>(\d+)</entry>`, "v1*2")
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 3, matches, "Expected 3 matches, got %d", matches)
@@ -186,7 +186,7 @@ func TestMultipleStringMatches(t *testing.T) {
     <name>Mary_modified</name>
 </data>`
 
-	result, mods, matches, err := ApiAdaptor(content, `<name>([A-Za-z]+)</name>`, `s1 = s1 .. "_modified"`)
+	result, mods, matches, err := APIAdaptor(content, `<name>([A-Za-z]+)</name>`, `s1 = s1 .. "_modified"`)
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 2, matches, "Expected 2 matches, got %d", matches)
@@ -205,7 +205,7 @@ func TestStringUpperCase(t *testing.T) {
     <user>MARY</user>
 </users>`
 
-	result, mods, matches, err := ApiAdaptor(content, `<user>([A-Za-z]+)</user>`, `s1 = string.upper(s1)`)
+	result, mods, matches, err := APIAdaptor(content, `<user>([A-Za-z]+)</user>`, `s1 = string.upper(s1)`)
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 2, matches, "Expected 2 matches, got %d", matches)
@@ -224,7 +224,7 @@ func TestStringConcatenation(t *testing.T) {
     <product>Banana_fruit</product>
 </products>`
 
-	result, mods, matches, err := ApiAdaptor(content, `<product>([A-Za-z]+)</product>`, `s1 = s1 .. "_fruit"`)
+	result, mods, matches, err := APIAdaptor(content, `<product>([A-Za-z]+)</product>`, `s1 = s1 .. "_fruit"`)
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 2, matches, "Expected 2 matches, got %d", matches)
@@ -254,7 +254,7 @@ func TestDecimalValues(t *testing.T) {
 	regex := regexp.MustCompile(`(?s)<value>([0-9.]+)</value>.*?<multiplier>([0-9.]+)</multiplier>`)
 	luaExpr := BuildLuaScript("v1 = v1 * v2")
 
-	result, _, _, err := ApiAdaptor(content, regex.String(), luaExpr)
+	result, _, _, err := APIAdaptor(content, regex.String(), luaExpr)
 	assert.NoError(t, err, "Error processing content: %v", err)
 
 	normalizedModified := normalizeWhitespace(result)
@@ -282,7 +282,7 @@ func TestLuaMathFunctions(t *testing.T) {
 	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>`)
 	luaExpr := BuildLuaScript("v1 = math.sqrt(v1)")
 
-	modifiedContent, _, _, err := ApiAdaptor(content, regex.String(), luaExpr)
+	modifiedContent, _, _, err := APIAdaptor(content, regex.String(), luaExpr)
 	assert.NoError(t, err, "Error processing content: %v", err)
 
 	normalizedModified := normalizeWhitespace(modifiedContent)
@@ -310,7 +310,7 @@ func TestDirectAssignment(t *testing.T) {
 	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>`)
 	luaExpr := BuildLuaScript("=0")
 
-	modifiedContent, _, _, err := ApiAdaptor(content, regex.String(), luaExpr)
+	modifiedContent, _, _, err := APIAdaptor(content, regex.String(), luaExpr)
 	assert.NoError(t, err, "Error processing content: %v", err)
 
 	normalizedModified := normalizeWhitespace(modifiedContent)
@@ -369,7 +369,7 @@ func TestStringAndNumericOperations(t *testing.T) {
 			luaExpr := BuildLuaScript(tt.luaExpression)
 
 			// Process with our function
-			result, modCount, _, err := ApiAdaptor(tt.input, pattern, luaExpr)
+			result, modCount, _, err := APIAdaptor(tt.input, pattern, luaExpr)
 			assert.NoError(t, err, "Process function failed: %v", err)
 
 			// Check results
@@ -430,7 +430,7 @@ func TestEdgeCases(t *testing.T) {
 			luaExpr := BuildLuaScript(tt.luaExpression)
 
 			// Process with our function
-			result, modCount, _, err := ApiAdaptor(tt.input, pattern, luaExpr)
+			result, modCount, _, err := APIAdaptor(tt.input, pattern, luaExpr)
 			assert.NoError(t, err, "Process function failed: %v", err)
 
 			// Check results
@@ -453,7 +453,7 @@ func TestNamedCaptureGroups(t *testing.T) {
     </item>
 </config>`
 
-	result, mods, matches, err := ApiAdaptor(content, `(?s)<value>(?<amount>\d+)</value>`, "amount = amount * 2")
+	result, mods, matches, err := APIAdaptor(content, `(?s)<value>(?<amount>\d+)</value>`, "amount = amount * 2")
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 1, matches, "Expected 1 match, got %d", matches)
@@ -474,7 +474,7 @@ func TestNamedCaptureGroupsNum(t *testing.T) {
     </item>
 </config>`
 
-	result, mods, matches, err := ApiAdaptor(content, `(?s)<value>(?<amount>!num)</value>`, "amount = amount * 2")
+	result, mods, matches, err := APIAdaptor(content, `(?s)<value>(?<amount>!num)</value>`, "amount = amount * 2")
 
 	assert.NoError(t, err, "Error processing content: %v", err)
 	assert.Equal(t, 1, matches, "Expected 1 match, got %d", matches)
@@ -495,7 +495,7 @@ func TestMultipleNamedCaptureGroups(t *testing.T) {
     <quantity>15</quantity>
 </product>`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`(?s)<name>(?<prodName>[^<]+)</name>.*?<price>(?<prodPrice>\d+\.\d+)</price>.*?<quantity>(?<prodQty>\d+)</quantity>`,
 		`prodName = string.upper(prodName)
 		 prodPrice = round(prodPrice + 8, 2)
@@ -518,7 +518,7 @@ func TestMixedIndexedAndNamedCaptures(t *testing.T) {
     <data>VALUE</data>
 </entry>`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`(?s)<id>(\d+)</id>.*?<data>(?<dataField>[^<]+)</data>`,
 		`v1 = v1 * 2
 		 dataField = string.upper(dataField)`)
@@ -550,7 +550,7 @@ func TestComplexNestedNamedCaptures(t *testing.T) {
 		</contact>
 	</person>`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`(?s)<details>.*?<name>(?<fullName>[^<]+)</name>.*?<age>(?<age>\d+)</age>`,
 		`fullName = string.upper(fullName) .. " (" .. age .. ")"`)
 
@@ -571,7 +571,7 @@ func TestNamedCaptureWithVariableReadback(t *testing.T) {
     <mana>300</mana>
 </stats>`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`(?s)<health>(?<hp>\d+)</health>.*?<mana>(?<mp>\d+)</mana>`,
 		`hp = hp * 1.5
 		 mp = mp * 1.5`)
@@ -587,7 +587,7 @@ func TestNamedCaptureWithSpecialCharsInName(t *testing.T) {
 
 	expected := `<data value="84" min="10" max="100" />`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<data value="(?<val_1>\d+)"`,
 		`val_1 = val_1 * 2`)
 
@@ -602,7 +602,7 @@ func TestEmptyNamedCapture(t *testing.T) {
 
 	expected := `<tag attr="default" />`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`attr="(?<value>.*?)"`,
 		`value = value == "" and "default" or value`)
 
@@ -617,7 +617,7 @@ func TestMultipleNamedCapturesInSameLine(t *testing.T) {
 
 	expected := `<rect x="20" y="40" width="200" height="100" />`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`x="(?<x>\d+)" y="(?<y>\d+)" width="(?<w>\d+)" height="(?<h>\d+)"`,
 		`x = x * 2
 		 y = y * 2
@@ -641,7 +641,7 @@ func TestConditionalNamedCapture(t *testing.T) {
 	<item status="inactive" count="10" />
 	`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<item status="(?<status>[^"]+)" count="(?<count>\d+)"`,
 		`count = status == "active" and count * 2 or count`)
 
@@ -662,7 +662,7 @@ func TestLuaFunctionsOnNamedCaptures(t *testing.T) {
 	<user name="JANE SMITH" role="admin" />
 	`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<user name="(?<name>[^"]+)" role="(?<role>[^"]+)"`,
 		`-- Capitalize first letters for regular users
 		 if role == "user" then
@@ -692,7 +692,7 @@ func TestNamedCaptureWithMath(t *testing.T) {
 	<item price="19.99" quantity="3" total="59.97" />
 	`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<item price="(?<price>\d+\.\d+)" quantity="(?<qty>\d+)"!any$`,
 		`-- Calculate and add total
 		 replacement = string.format('<item price="%s" quantity="%s" total="%.2f" />',
@@ -712,7 +712,7 @@ func TestNamedCaptureWithGlobals(t *testing.T) {
 
 	expected := `<temp unit="F">77</temp>`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<temp unit="(?<unit>[CF]?)">(?<value>\d+)</temp>`,
 		`if unit == "C" then
 		  value = value * 9/5 + 32
@@ -739,7 +739,7 @@ func TestMixedDynamicAndNamedCaptures(t *testing.T) {
 	<color rgb="0,255,0" name="GREEN" hex="#00FF00" />
 	`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<color rgb="(?<r>\d+),(?<g>\d+),(?<b>\d+)" name="(?<colorName>[^"]+)" />`,
 		`-- Uppercase the name
 		 colorName = string.upper(colorName)
@@ -765,7 +765,7 @@ func TestNamedCapturesWithMultipleReferences(t *testing.T) {
 
 	expected := `<text format="uppercase" length="11">HELLO WORLD</text>`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<text>(?<content>[^<]+)</text>`,
 		`local uppercaseContent = string.upper(content)
 		 local contentLength = string.len(content)
@@ -783,7 +783,7 @@ func TestNamedCaptureWithJsonData(t *testing.T) {
 
 	expected := `<data>{"name":"JOHN","age":30}</data>`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<data>(?<json>\{.*?\})</data>`,
 		`-- Parse JSON (simplified, assumes valid JSON)
 		 local name = json:match('"name":"([^"]+)"')
@@ -813,7 +813,7 @@ func TestNamedCaptureInXML(t *testing.T) {
 	</product>
 	`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`(?s)<price currency="(?<currency>[^"]+)">(?<price>\d+\.\d+)</price>.*?<stock>(?<stock>\d+)</stock>`,
 		`-- Add 20% to price if USD
 		 if currency == "USD" then
@@ -870,7 +870,7 @@ func TestComprehensiveNamedCaptures(t *testing.T) {
 	</products>
 	`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`(?s)<product sku="(?<sku>[^"]+)" status="(?<status>[^"]+)"[^>]*>\s*<name>(?<product_name>[^<]+)</name>\s*<price currency="(?<currency>[^"]+)">(?<price>\d+\.\d+)</price>\s*<quantity>(?<qty>\d+)</quantity>`,
 		`-- Only process in-stock items
 		if status == "in-stock" then
@@ -924,7 +924,7 @@ func TestVariousNamedCaptureFormats(t *testing.T) {
 	</data>
 	`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`<entry id="(?<id_num>\d+)" value="(?<val>\d+)"(?: status="(?<status>[^"]*)")? />`,
 		`-- Prefix the ID with "ID-"
 		id_num = "ID-" .. id_num
@@ -963,7 +963,7 @@ func TestSimpleNamedCapture(t *testing.T) {
 
 	expected := `<product name="WIDGET" price="19.99"/>`
 
-	result, mods, matches, err := ApiAdaptor(content,
+	result, mods, matches, err := APIAdaptor(content,
 		`name="(?<product_name>[^"]+)"`,
 		`product_name = string.upper(product_name)`)
 

toml_test.go

@@ -404,6 +404,7 @@ files = ["test.txt"
 
 	invalidFile := filepath.Join(tmpDir, "invalid.toml")
 	err = os.WriteFile(invalidFile, []byte(invalidTOML), 0644)
+	assert.NoError(t, err, "Should write invalid TOML file")
 
 	commands, err := utils.LoadCommandsFromTomlFiles("invalid.toml")
 	assert.Error(t, err, "Should return error for invalid TOML syntax")
@@ -418,6 +419,7 @@ files = ["test.txt"
 	// Test 3: Empty TOML file creates an error (this is expected behavior)
 	emptyFile := filepath.Join(tmpDir, "empty.toml")
 	err = os.WriteFile(emptyFile, []byte(""), 0644)
+	assert.NoError(t, err, "Should write empty TOML file")
 
 	commands, err = utils.LoadCommandsFromTomlFiles("empty.toml")
 	assert.Error(t, err, "Should return error for empty TOML file")
@@ -508,4 +510,4 @@ func TestYAMLToTOMLConversion(t *testing.T) {
 	assert.Equal(t, tomlData, originalTomlData, "TOML file content should be unchanged")
 
 	t.Logf("YAML to TOML conversion test completed successfully")
-}
+}