Throw an IncorrectNumberOfFunctionParametersException if a function gets more arguments than it supports (#117)

* Throw an IncorrectNumberOfFunctionParametersException if a function gets more arguments than it supports

* Update CustomFunction.php

Code Style

Co-authored-by: Bruce Wells <brucekwells@gmail.com>

2 files changed, 19 insertions, 1 deletions

diff --git a/src/NXP/Classes/CustomFunction.php b/src/NXP/Classes/CustomFunction.php
index 6e9ffc5..43c5b55 100644
--- a/src/NXP/Classes/CustomFunction.php
+++ b/src/NXP/Classes/CustomFunction.php
@@ -15,6 +15,8 @@ class CustomFunction
      */
     public $function;
 
+    private bool $isVariadic;
+    private int $totalParamCount;
     private int $requiredParamCount;
 
     /**
@@ -26,7 +28,10 @@ class CustomFunction
     {
         $this->name = $name;
         $this->function = $function;
-        $this->requiredParamCount = (new ReflectionFunction($function))->getNumberOfRequiredParameters();
+        $reflection = (new ReflectionFunction($function));
+        $this->isVariadic = $reflection->isVariadic();
+        $this->totalParamCount = $reflection->getNumberOfParameters();
+        $this->requiredParamCount = $reflection->getNumberOfRequiredParameters();
 
     }
 
@@ -40,6 +45,9 @@ class CustomFunction
         if ($paramCountInStack < $this->requiredParamCount) {
             throw new IncorrectNumberOfFunctionParametersException($this->name);
         }
+        if ($paramCountInStack > $this->totalParamCount && ! $this->isVariadic) {
+            throw new IncorrectNumberOfFunctionParametersException($this->name);
+        }
         $args = [];
 
         if ($paramCountInStack > 0) {
diff --git a/tests/MathTest.php b/tests/MathTest.php
index 94a14d4..59ce207 100644
--- a/tests/MathTest.php
+++ b/tests/MathTest.php
@@ -674,6 +674,16 @@ class MathTest extends TestCase
         $calculator->execute('myfunc(1)');
     }
 
+    public function testFunctionIncorrectNumberOfParametersTooMany() : void
+    {
+        $calculator = new MathExecutor();
+        $this->expectException(IncorrectNumberOfFunctionParametersException::class);
+        $calculator->addFunction('myfunc', static function($arg1, $arg2) {
+            return $arg1 + $arg2;
+        });
+        $calculator->execute('myfunc(1,2,3)');
+    }
+
     public function testFunctionIf() : void
     {
         $calculator = new MathExecutor();