Support unlimited args for min, max default funcs. (#106)

* Support unlimited args for min, max default funcs.

Default functions max and min were requiring 2 arguments strictly. Now they supoort unlimited args, same as php's min, max funcs.

* Improved functions: support unlimited parameters (see min, max funcs), optional parameters (see round func), parameters with types (see round func, throws IncorrectFunctionParameterException on unmatched type, union types and intersection types not supported because of min php level! there is a todo for this, to support them later @see CustomFunction@execute) Also added unittests for improvements.

* Run php-cs-fixer fix

src/NXP/Classes/Calculator.php

@@ -74,7 +74,7 @@ class Calculator
                 if (! \array_key_exists($token->value, $this->functions)) {
                     throw new UnknownFunctionException($token->value);
                 }
-                $stack[] = $this->functions[$token->value]->execute($stack);
+                $stack[] = $this->functions[$token->value]->execute($stack, $token->paramCount);
             } elseif (Token::Operator === $token->type) {
                 if (! \array_key_exists($token->value, $this->operators)) {
                     throw new UnknownOperatorException($token->value);

src/NXP/Classes/CustomFunction.php

@@ -2,6 +2,7 @@
 
 namespace NXP\Classes;
 
+use NXP\Exception\IncorrectFunctionParameterException;
 use NXP\Exception\IncorrectNumberOfFunctionParametersException;
 use ReflectionException;
 use ReflectionFunction;
@@ -15,41 +16,48 @@ class CustomFunction
      */
     public $function;
 
-    public int $places = 0;
+    private ReflectionFunction $reflectionFunction;
 
     /**
      * CustomFunction constructor.
      *
      * @throws ReflectionException
-     * @throws IncorrectNumberOfFunctionParametersException
      */
-    public function __construct(string $name, callable $function, ?int $places = null)
+    public function __construct(string $name, callable $function)
     {
         $this->name = $name;
         $this->function = $function;
+        $this->reflectionFunction = new ReflectionFunction($function);
 
-        if (null === $places) {
-            $reflection = new ReflectionFunction($function);
-            $this->places = $reflection->getNumberOfParameters();
-        } else {
-            $this->places = $places;
-        }
     }
 
     /**
      * @param array<Token> $stack
      *
-     * @throws IncorrectNumberOfFunctionParametersException
+     * @throws IncorrectNumberOfFunctionParametersException|IncorrectFunctionParameterException
      */
-    public function execute(array &$stack) : Token
+    public function execute(array &$stack, int $paramCountInStack) : Token
     {
-        if (\count($stack) < $this->places) {
+        if ($paramCountInStack < $this->reflectionFunction->getNumberOfRequiredParameters()) {
             throw new IncorrectNumberOfFunctionParametersException($this->name);
         }
         $args = [];
 
-        for ($i = 0; $i < $this->places; $i++) {
+        if ($paramCountInStack > 0) {
-            \array_unshift($args, \array_pop($stack)->value);
+            $reflectionParameters = $this->reflectionFunction->getParameters();
+
+            for ($i = 0; $i < $paramCountInStack; $i++) {
+                $value = \array_pop($stack)->value;
+                $valueType = \gettype($value);
+                $reflectionParameter = $reflectionParameters[\min(\count($reflectionParameters) - 1, $i)];
+                //TODO to support type check for union types (php >= 8.0) and intersection types (php >= 8.1), we should increase min php level in composer.json
+                // For now, only support basic types. @see testFunctionParameterTypes
+                if ($reflectionParameter->hasType() && $reflectionParameter->getType()->getName() !== $valueType){
+                    throw new IncorrectFunctionParameterException();
+                }
+
+                \array_unshift($args, $value);
+            }
         }
 
         $result = \call_user_func_array($this->function, $args);

src/NXP/Classes/Token.php

@@ -28,6 +28,8 @@ class Token
 
     public ?string $name;
 
+    public ?int $paramCount = null;//to store function parameter count in stack
+
     /**
      * Token constructor.
      *

src/NXP/Classes/Tokenizer.php

@@ -20,7 +20,7 @@ use SplStack;
  */
 class Tokenizer
 {
-    /** @var array<Token>  */
+    /** @var array<Token> */
     public array $tokens = [];
 
     private string $input = '';
@@ -31,7 +31,7 @@ class Tokenizer
 
     private bool $allowNegative = true;
 
-    /** @var array<Operator>  */
+    /** @var array<Operator> */
     private array $operators = [];
 
     private bool $inSingleQuotedString = false;
@@ -99,8 +99,8 @@ class Tokenizer
 
                         break;
                     }
-                    // no break
+                // no break
-                    // Intentionally fall through
+                // Intentionally fall through
                 case $this->isAlpha($ch):
                     if (\strlen($this->numberBuffer)) {
                         $this->emptyNumberBufferAsLiteral();
@@ -196,8 +196,8 @@ class Tokenizer
     }
 
     /**
-     * @throws IncorrectBracketsException
      * @throws UnknownOperatorException
+     * @throws IncorrectBracketsException
      * @return Token[] Array of tokens in revers polish notation
      */
     public function buildReversePolishNotation() : array
@@ -205,6 +205,10 @@ class Tokenizer
         $tokens = [];
         /** @var SplStack<Token> $stack */
         $stack = new SplStack();
+        /**
+         * @var SplStack<int> $paramCounter
+         */
+        $paramCounter = new SplStack();
 
         foreach ($this->tokens as $token) {
             switch ($token->type) {
@@ -213,9 +217,21 @@ class Tokenizer
                 case Token::String:
                     $tokens[] = $token;
 
+                    if ($paramCounter->count() > 0 && 0 === $paramCounter->top()) {
+                        $paramCounter->push($paramCounter->pop() + 1);
+                    }
+
                     break;
 
                 case Token::Function:
+                    if ($paramCounter->count() > 0 && 0 === $paramCounter->top()) {
+                        $paramCounter->push($paramCounter->pop() + 1);
+                    }
+                    $stack->push($token);
+                    $paramCounter->push(0);
+
+                    break;
+
                 case Token::LeftParenthesis:
                     $stack->push($token);
 
@@ -228,6 +244,7 @@ class Tokenizer
                         }
                         $tokens[] = $stack->pop();
                     }
+                    $paramCounter->push($paramCounter->pop() + 1);
 
                     break;
 
@@ -270,7 +287,12 @@ class Tokenizer
                     }
 
                     if ($stack->count() > 0 && Token::Function == $stack->top()->type) {
-                        $tokens[] = $stack->pop();
+                        /**
+                         * @var Token $f
+                         */
+                        $f = $stack->pop();
+                        $f->paramCount = $paramCounter->pop();
+                        $tokens[] = $f;
                     }
 
                     break;

src/NXP/Exception/IncorrectFunctionParameterException.php

@@ -0,0 +1,16 @@
+<?php
+
+/**
+ * This file is part of the MathExecutor package
+ *
+ * (c) Alexander Kiryukhin
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code
+ */
+
+namespace NXP\Exception;
+
+class IncorrectFunctionParameterException extends MathExecutorException
+{
+}

src/NXP/MathExecutor.php

@@ -116,15 +116,14 @@ class MathExecutor
      *
      * @param string        $name     Name of function
      * @param callable|null $function Function
-     * @param int|null      $places   Count of arguments
      *
-     * @throws Exception\IncorrectNumberOfFunctionParametersException
      * @throws ReflectionException
+     * @throws Exception\IncorrectNumberOfFunctionParametersException
      * @return MathExecutor
      */
-    public function addFunction(string $name, ?callable $function = null, ?int $places = null) : self
+    public function addFunction(string $name, ?callable $function = null) : self
     {
-        $this->functions[$name] = new CustomFunction($name, $function, $places);
+        $this->functions[$name] = new CustomFunction($name, $function);
 
         return $this;
     }
@@ -432,13 +431,13 @@ class MathExecutor
           'log' => static fn($arg) => \log($arg),
           'log10' => static fn($arg) => \log10($arg),
           'log1p' => static fn($arg) => \log1p($arg),
-          'max' => static fn($arg1, $arg2) => \max($arg1, $arg2),
+          'max' => static fn($arg1, $arg2, ...$args) => \max($arg1, $arg2, ...$args),
-          'min' => static fn($arg1, $arg2) => \min($arg1, $arg2),
+          'min' => static fn($arg1, $arg2, ...$args) => \min($arg1, $arg2, ...$args),
           'octdec' => static fn($arg) => \octdec($arg),
           'pi' => static fn() => M_PI,
           'pow' => static fn($arg1, $arg2) => $arg1 ** $arg2,
           'rad2deg' => static fn($arg) => \rad2deg($arg),
-          'round' => static fn($arg) => \round($arg),
+          'round' => static fn($num, int $precision = 0) => \round($num, $precision),
           'sin' => static fn($arg) => \sin($arg),
           'sinh' => static fn($arg) => \sinh($arg),
           'sec' => static fn($arg) => 1 / \cos($arg),

tests/MathTest.php

@@ -14,6 +14,7 @@ namespace NXP\Tests;
 use Exception;
 use NXP\Exception\DivisionByZeroException;
 use NXP\Exception\IncorrectExpressionException;
+use NXP\Exception\IncorrectFunctionParameterException;
 use NXP\Exception\IncorrectNumberOfFunctionParametersException;
 use NXP\Exception\MathExecutorException;
 use NXP\Exception\UnknownFunctionException;
@@ -243,6 +244,7 @@ class MathTest extends TestCase
           ['-(4*-2)-5'],
           ['-(-4*2) - 5'],
           ['-4*-5'],
+          ['max(1,2,4.9,3)']
         ];
     }
 
@@ -323,6 +325,45 @@ class MathTest extends TestCase
         $this->assertEquals(\round(100 / 30), $calculator->execute('round(100/30)'));
     }
 
+    public function testFunctionUnlimitedParameters() : void
+    {
+        $calculator = new MathExecutor();
+        $calculator->addFunction('max', static function($arg1, $arg2, ...$args) {
+            return \max($arg1, $arg2, ...$args);
+        });
+        $this->assertEquals(\max(4, 6, 8.1, 2, 7), $calculator->execute('max(4,6,8.1,2,7)'));
+    }
+
+    public function testFunctionOptionalParameters() : void
+    {
+        $calculator = new MathExecutor();
+        $calculator->addFunction('round', static function($num, $precision = 0) {
+            return \round($num, $precision);
+        });
+        $this->assertEquals(\round(11.176), $calculator->execute('round(11.176)'));
+        $this->assertEquals(\round(11.176, 2), $calculator->execute('round(11.176,2)'));
+    }
+
+    public function testFunctionParameterTypes() : void
+    {
+        $calculator = new MathExecutor();
+        $this->expectException(IncorrectFunctionParameterException::class);
+        $calculator->addFunction('myfunc', static function(string $name, int $age) {
+            return $name . $age;
+        });
+        $calculator->execute('myfunc(22, "John Doe")');
+    }
+
+    public function testFunctionIncorrectNumberOfParameters() : void
+    {
+        $calculator = new MathExecutor();
+        $this->expectException(IncorrectNumberOfFunctionParametersException::class);
+        $calculator->addFunction('myfunc', static function($arg1, $arg2) {
+            return $arg1 + $arg2;
+        });
+        $calculator->execute('myfunc(1)');
+    }
+
     public function testFunctionIf() : void
     {
         $calculator = new MathExecutor();