extract function invocation checks from script call

Author: mgomes

docs/architecture.md

@@ -28,6 +28,7 @@ Key files:
 - `vibes/execution_call_globals.go` (strict global validation and call-time global binding)
 - `vibes/execution_call_classes.go` (call-time class body initialization in class-local scope)
 - `vibes/execution_call_env.go` (call env prep: argument rebind/bind and memory validation)
+- `vibes/execution_call_invoke.go` (function frame execution, return type validation, memory checks)
 - `vibes/execution_function_args.go` (function argument/default/type/ivar binding helpers)
 - `vibes/execution_calls.go` (callable dispatch + function invocation)
 - `vibes/execution_call_expr.go` (call expression target/args/kwargs/block evaluation)

vibes/execution_call_invoke.go

@@ -0,0 +1,24 @@
+package vibes
+
+func executeFunctionForCall(exec *Execution, fn *ScriptFunction, callEnv *Env) (Value, error) {
+	if err := exec.pushFrame(fn.Name, fn.Pos); err != nil {
+		return NewNil(), err
+	}
+	val, returned, err := exec.evalStatements(fn.Body, callEnv)
+	exec.popFrame()
+	if err != nil {
+		return NewNil(), err
+	}
+	if fn.ReturnTy != nil {
+		if err := checkValueType(val, fn.ReturnTy); err != nil {
+			return NewNil(), exec.errorAt(fn.Pos, "%s", formatReturnTypeMismatch(fn.Name, err))
+		}
+	}
+	if err := exec.checkMemoryWith(val); err != nil {
+		return NewNil(), err
+	}
+	if returned {
+		return val, nil
+	}
+	return val, nil
+}

vibes/execution_script.go

@@ -58,24 +58,9 @@ func (s *Script) Call(ctx context.Context, name string, args []Value, opts CallO
 		return NewNil(), err
 	}
 
-	if err := exec.pushFrame(fn.Name, fn.Pos); err != nil {
-		return NewNil(), err
-	}
-	val, returned, err := exec.evalStatements(fn.Body, callEnv)
-	exec.popFrame()
+	val, err := executeFunctionForCall(exec, fn, callEnv)
 	if err != nil {
 		return NewNil(), err
 	}
-	if fn.ReturnTy != nil {
-		if err := checkValueType(val, fn.ReturnTy); err != nil {
-			return NewNil(), exec.errorAt(fn.Pos, "%s", formatReturnTypeMismatch(fn.Name, err))
-		}
-	}
-	if err := exec.checkMemoryWith(val); err != nil {
-		return NewNil(), err
-	}
-	if returned {
-		return val, nil
-	}
 	return val, nil
 }