feat: pass Locals to UserFunction for name resolution

- Update UserFunction to store Locals for resolving variable scope
- Modify Call method to pass Locals to Eval during function execution
- Update Run API to pass resolved locals to Interpret method
- Add semantic error handling in Run API

Author: ryan-gang

internal/lox/api/run_api.go

@@ -15,10 +15,14 @@ func Run(source string) (string, int, string) {
 	tokens := scanner.ScanTokens(mockStdout, mockStderr)
 	parser := lox.NewParser(tokens)
 	statements := parser.Parse(mockStdout, mockStderr)
-	lox.Interpret(statements, mockStdout, mockStderr)
+	locals, err := lox.Resolve(statements)
+	if err != nil || lox.HadSemanticError {
+		return "", 65, err.Error()
+	}
+	lox.Interpret(statements, locals, mockStdout, mockStderr)
 
 	exitCode := 0
-	if lox.HadParseError {
+	if lox.HadParseError || lox.HadSemanticError {
 		exitCode = 65
 	} else if lox.HadRuntimeError {
 		exitCode = 70

internal/lox/functions.go

@@ -37,6 +37,7 @@ type UserFunction struct {
 	Callable
 	Declaration *Function
 	Closure     *Environment
+	Locals      Locals // TODO: Pass pointer to Locals
 }
 
 // NewUserFunction creates a new UserFunction
@@ -54,7 +55,7 @@ func (u *UserFunction) Call(arguments []interface{}, globalEnv *Environment, std
 	}
 
 	for _, stmt := range u.Declaration.Body {
-		_, err := Eval(stmt, env, stdout, stderr)
+		_, err := Eval(stmt, env, u.Locals, stdout, stderr)
 
 		if err != nil {
 			if r, ok := err.(ReturnError); ok {