Drop php74 (#120)

* PHPStan Level 6

* Drop PHP 7.4 support

* Add PHPStan badge to readme

* Code style cleanup

12 files changed, 72 insertions, 120 deletions

diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 4967599..2db0a46 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php: [8.2, 8.1, 8.0, 7.4]
+        php: [8.2, 8.1, 8.0]
         dependency-version: [prefer-lowest, prefer-stable]
         os: [ubuntu-latest, windows-latest]
 
diff --git a/README.md b/README.md
index 0e88f34..b84aace 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# MathExecutor [![Tests](https://github.com/neonxp/MathExecutor/workflows/Tests/badge.svg)](https://github.com/neonxp/MathExecutor/actions?query=workflow%3ATests)
+# MathExecutor [![Tests](https://github.com/neonxp/MathExecutor/workflows/Tests/badge.svg)](https://github.com/neonxp/MathExecutor/actions?query=workflow%3ATests) ![](https://img.shields.io/badge/PHPStan-level%206-brightgreen.svg?style=flat)
 
 # A simple and extensible math expressions calculator
 
diff --git a/composer.json b/composer.json
index 6d3759d..1defb99 100644
--- a/composer.json
+++ b/composer.json
@@ -32,7 +32,8 @@
   },
   "require-dev": {
     "phpunit/phpunit": ">=9.0",
-    "friendsofphp/php-cs-fixer": "^3.8"
+    "friendsofphp/php-cs-fixer": "^3.8",
+    "phpstan/phpstan": "^1.9"
   },
   "autoload": {
     "psr-4": {
diff --git a/phpstan.neon b/phpstan.neon
deleted file mode 100644
index bed17ae..0000000
--- a/phpstan.neon
+++ /dev/null
@@ -1,9 +0,0 @@
-parameters:
-  level: 6
-  paths:
-      - ./
-  excludes_analyse:
-     - vendor/*
-     - tests/*
-  bootstrapFiles:
-     - vendor/autoload.php
\ No newline at end of file
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
new file mode 100644
index 0000000..b05dc95
--- /dev/null
+++ b/phpstan.neon.dist
@@ -0,0 +1,7 @@
+parameters:
+	level: 6
+	errorFormat: raw
+	editorUrl: '%%file%% %%line%% %%column%%: %%error%%'
+	paths:
+		- src
+		- tests
diff --git a/src/NXP/Classes/Calculator.php b/src/NXP/Classes/Calculator.php
index 6b63503..80dee36 100644
--- a/src/NXP/Classes/Calculator.php
+++ b/src/NXP/Classes/Calculator.php
@@ -20,22 +20,14 @@ use NXP\Exception\UnknownVariableException;
  */
 class Calculator
 {
-    /** @var array<string, CustomFunction>  */
-    private array $functions = [];
-
-    /** @var array<Operator>  */
-    private array $operators = [];
-
     /**
      * @todo PHP8: Use constructor property promotion -> public function __construct(private array $functions, private array $operators)
      *
      * @param array<string, CustomFunction> $functions
      * @param array<Operator> $operators
      */
-    public function __construct(array $functions, array $operators)
+    public function __construct(private array $functions, private array $operators)
     {
-        $this->functions = $functions;
-        $this->operators = $operators;
     }
 
     /**
diff --git a/src/NXP/Classes/CustomFunction.php b/src/NXP/Classes/CustomFunction.php
index 85db379..e4cdd76 100644
--- a/src/NXP/Classes/CustomFunction.php
+++ b/src/NXP/Classes/CustomFunction.php
@@ -8,8 +8,6 @@ use ReflectionFunction;
 
 class CustomFunction
 {
-    public string $name = '';
-
     /**
      * @var callable $function
      */
@@ -26,9 +24,8 @@ class CustomFunction
      *
      * @throws ReflectionException
      */
-    public function __construct(string $name, callable $function)
+    public function __construct(public string $name, callable $function)
     {
-        $this->name = $name;
         $this->function = $function;
         $reflection = (new ReflectionFunction($function));
         $this->isVariadic = $reflection->isVariadic();
diff --git a/src/NXP/Classes/Operator.php b/src/NXP/Classes/Operator.php
index 7dee06d..231b1d9 100644
--- a/src/NXP/Classes/Operator.php
+++ b/src/NXP/Classes/Operator.php
@@ -7,12 +7,6 @@ use ReflectionFunction;
 
 class Operator
 {
-    public string $operator = '';
-
-    public bool $isRightAssoc = false;
-
-    public int $priority = 0;
-
     /**
      * @var callable(\SplStack)
      */
@@ -23,11 +17,8 @@ class Operator
     /**
      * Operator constructor.
      */
-    public function __construct(string $operator, bool $isRightAssoc, int $priority, callable $function)
+    public function __construct(public string $operator, public bool $isRightAssoc, public int $priority, callable $function)
     {
-        $this->operator = $operator;
-        $this->isRightAssoc = $isRightAssoc;
-        $this->priority = $priority;
         $this->function = $function;
         $reflection = new ReflectionFunction($function);
         $this->places = $reflection->getNumberOfParameters();
diff --git a/src/NXP/Classes/Token.php b/src/NXP/Classes/Token.php
index 7532e77..ae460a9 100644
--- a/src/NXP/Classes/Token.php
+++ b/src/NXP/Classes/Token.php
@@ -22,22 +22,13 @@ class Token
 
     public const Space = 'space';
 
-    public string $type = self::Literal;
-
-    public $value;
-
-    public ?string $name;
-
     public ?int $paramCount = null;//to store function parameter count in stack
 
     /**
      * Token constructor.
      *
      */
-    public function __construct(string $type, $value, ?string $name = null)
+    public function __construct(public string $type, public mixed $value, public ?string $name = null)
     {
-        $this->type = $type;
-        $this->value = $value;
-        $this->name = $name;
     }
 }
diff --git a/src/NXP/Classes/Tokenizer.php b/src/NXP/Classes/Tokenizer.php
index a74bff6..656961a 100644
--- a/src/NXP/Classes/Tokenizer.php
+++ b/src/NXP/Classes/Tokenizer.php
@@ -23,17 +23,12 @@ class Tokenizer
     /** @var array<Token> */
     public array $tokens = [];
 
-    private string $input = '';
-
     private string $numberBuffer = '';
 
     private string $stringBuffer = '';
 
     private bool $allowNegative = true;
 
-    /** @var array<Operator> */
-    private array $operators = [];
-
     private bool $inSingleQuotedString = false;
 
     private bool $inDoubleQuotedString = false;
@@ -42,10 +37,8 @@ class Tokenizer
      * Tokenizer constructor.
      * @param Operator[] $operators
      */
-    public function __construct(string $input, array $operators)
+    public function __construct(private string $input, private array $operators)
     {
-        $this->input = $input;
-        $this->operators = $operators;
     }
 
     public function tokenize() : self
@@ -142,7 +135,7 @@ class Tokenizer
                     break;
                 /** @noinspection PhpMissingBreakStatementInspection */
                 case 'e' === \strtolower($ch):
-                    if (\strlen($this->numberBuffer) && false !== \strpos($this->numberBuffer, '.')) {
+                    if (\strlen($this->numberBuffer) && \str_contains($this->numberBuffer, '.')) {
                         $this->numberBuffer .= 'e';
                         $this->allowNegative = false;
 
@@ -330,7 +323,7 @@ class Tokenizer
                                 break;
                             }
                             $tokens[] = $ctoken;
-                        } catch (RuntimeException $e) {
+                        } catch (RuntimeException) {
                             throw new IncorrectBracketsException();
                         }
                     }
diff --git a/src/NXP/MathExecutor.php b/src/NXP/MathExecutor.php
index e991586..c857e99 100644
--- a/src/NXP/MathExecutor.php
+++ b/src/NXP/MathExecutor.php
@@ -140,9 +140,8 @@ class MathExecutor
      * Get a specific var
      *
      * @throws UnknownVariableException if VarNotFoundHandler is not set
-     * @return int|float
      */
-    public function getVar(string $variable)
+    public function getVar(string $variable) : mixed
     {
         if (! \array_key_exists($variable, $this->variables)) {
             if ($this->onVarNotFound) {
@@ -160,7 +159,7 @@ class MathExecutor
      *
      * @throws MathExecutorException if the value is invalid based on the default or custom validator
      */
-    public function setVar(string $variable, $value) : self
+    public function setVar(string $variable, mixed $value) : self
     {
         if ($this->onVarValidation) {
             \call_user_func($this->onVarValidation, $variable, $value);
@@ -273,8 +272,6 @@ class MathExecutor
 
     /**
      * Remove a specific operator
-     *
-     * @return array<Operator> of operator class names
      */
     public function removeOperator(string $operator) : self
     {
@@ -380,7 +377,7 @@ class MathExecutor
             180,
             false
           ],
-          '^' => [static fn ($a, $b) => \pow($a, $b), 220, true],
+          '^' => [static fn ($a, $b) => $a ** $b, 220, true],
           '%' => [static fn ($a, $b) => $a % $b, 180, false],
           '&&' => [static fn ($a, $b) => $a && $b, 100, false],
           '||' => [static fn ($a, $b) => $a || $b, 90, false],
@@ -521,7 +518,7 @@ class MathExecutor
      * Default variable validation, ensures that the value is a scalar or array.
      * @throws MathExecutorException if the value is not a scalar
      */
-    protected function defaultVarValidation(string $variable, $value) : void
+    protected function defaultVarValidation(string $variable, mixed $value) : void
     {
         if (! \is_scalar($value) && ! \is_array($value) && null !== $value) {
             $type = \gettype($value);
diff --git a/tests/MathTest.php b/tests/MathTest.php
index 0c87c45..2c9197f 100644
--- a/tests/MathTest.php
+++ b/tests/MathTest.php
@@ -31,12 +31,13 @@ class MathTest extends TestCase
         $calculator = new MathExecutor();
 
         /** @var float $phpResult */
+        $phpResult = 0.0;
         eval('$phpResult = ' . $expression . ';');
 
         try {
             $result = $calculator->execute($expression);
         } catch (Exception $e) {
-            $this->fail(\sprintf('Exception: %s (%s:%d), expression was: %s', \get_class($e), $e->getFile(), $e->getLine(), $expression));
+            $this->fail(\sprintf('Exception: %s (%s:%d), expression was: %s', $e::class, $e->getFile(), $e->getLine(), $expression));
         }
         $this->assertEquals($phpResult, $result, "Expression was: {$expression}");
     }
@@ -47,6 +48,8 @@ class MathTest extends TestCase
      * Most tests can go in here.  The idea is that each expression will be evaluated by MathExecutor and by PHP with eval.
      * The results should be the same.  If they are not, then the test fails.  No need to add extra test unless you are doing
      * something more complex and not a simple mathmatical expression.
+     *
+     * @return array<array<string>>
      */
     public function providerExpressions()
     {
@@ -270,12 +273,13 @@ class MathTest extends TestCase
         }
 
         /** @var float $phpResult */
+        $phpResult = 0.0;
         eval('$phpResult = ' . $expected . ';');
 
         try {
             $result = $calculator->execute($expression);
         } catch (Exception $e) {
-            $this->fail(\sprintf('Exception: %s (%s:%d), expression was: %s', \get_class($e), $e->getFile(), $e->getLine(), $expression));
+            $this->fail(\sprintf('Exception: %s (%s:%d), expression was: %s', $e::class, $e->getFile(), $e->getLine(), $expression));
         }
         $this->assertEquals($phpResult, $result, "Expression was: {$expression}");
     }
@@ -286,6 +290,8 @@ class MathTest extends TestCase
      * Most tests can go in here.  The idea is that each expression will be evaluated by MathExecutor and by PHP with eval.
      * The results should be the same.  If they are not, then the test fails.  No need to add extra test unless you are doing
      * something more complex and not a simple mathmatical expression.
+     *
+     * @return array<array<string>>
      */
     public function bcMathExpressions()
     {
@@ -505,6 +511,8 @@ class MathTest extends TestCase
      * Incorrect Expressions data provider
      *
      * These expressions should not pass validation
+     *
+     * @return array<array<string>>
      */
     public function incorrectExpressions()
     {
@@ -592,9 +600,7 @@ class MathTest extends TestCase
         $this->assertEquals("'teststring", $calculator->execute("'\'teststring'"));
         $this->assertEquals("teststring'", $calculator->execute("'teststring\''"));
 
-        $calculator->addFunction('concat', static function($arg1, $arg2) {
-            return $arg1 . $arg2;
-        });
+        $calculator->addFunction('concat', static fn ($arg1, $arg2) => $arg1 . $arg2);
         $this->assertEquals('test"ing', $calculator->execute('concat("test\"","ing")'));
         $this->assertEquals("test'ing", $calculator->execute("concat('test\'','ing')"));
     }
@@ -608,7 +614,7 @@ class MathTest extends TestCase
         $this->assertEquals(\max([1, 5, 2]), $calculator->execute('max(array(1, 5, 2))'));
         $calculator->addFunction('arr_with_max_elements', static function($arg1, ...$args) {
             $args = \is_array($arg1) ? $arg1 : [$arg1, ...$args];
-            \usort($args, static fn ($arr1, $arr2) => \count($arr2) <=> \count($arr1));
+            \usort($args, static fn ($arr1, $arr2) => (\is_countable($arr2) ? \count($arr2) : 0) <=> \count($arr1));
 
             return $args[0];
         });
@@ -619,9 +625,7 @@ class MathTest extends TestCase
     {
         $calculator = new MathExecutor();
 
-        $calculator->addFunction('concat', static function($arg1, $arg2) {
-            return $arg1 . $arg2;
-        });
+        $calculator->addFunction('concat', static fn ($arg1, $arg2) => $arg1 . $arg2);
         $this->assertEquals('testing', $calculator->execute('concat("test","ing")'));
         $this->assertEquals('testing', $calculator->execute("concat('test','ing')"));
     }
@@ -629,18 +633,14 @@ class MathTest extends TestCase
     public function testFunction() : void
     {
         $calculator = new MathExecutor();
-        $calculator->addFunction('round', static function($arg) {
-            return \round($arg);
-        });
+        $calculator->addFunction('round', static fn ($arg) => \round($arg));
         $this->assertEquals(\round(100 / 30), $calculator->execute('round(100/30)'));
     }
 
     public function testFunctionUnlimitedParameters() : void
     {
         $calculator = new MathExecutor();
-        $calculator->addFunction('give_me_an_array', static function() {
-            return [5, 3, 7, 9, 8];
-        });
+        $calculator->addFunction('give_me_an_array', static fn () => [5, 3, 7, 9, 8]);
         $this->assertEquals(6.4, $calculator->execute('avg(give_me_an_array())'));
         $this->assertEquals(10, $calculator->execute('avg(12,8,15,5)'));
         $this->assertEquals(3, $calculator->execute('min(give_me_an_array())'));
@@ -657,9 +657,7 @@ class MathTest extends TestCase
     public function testFunctionOptionalParameters() : void
     {
         $calculator = new MathExecutor();
-        $calculator->addFunction('round', static function($num, $precision = 0) {
-            return \round($num, $precision);
-        });
+        $calculator->addFunction('round', static fn ($num, $precision = 0) => \round($num, $precision));
         $this->assertEquals(\round(11.176), $calculator->execute('round(11.176)'));
         $this->assertEquals(\round(11.176, 2), $calculator->execute('round(11.176,2)'));
     }
@@ -668,9 +666,7 @@ class MathTest extends TestCase
     {
         $calculator = new MathExecutor();
         $this->expectException(IncorrectNumberOfFunctionParametersException::class);
-        $calculator->addFunction('myfunc', static function($arg1, $arg2) {
-            return $arg1 + $arg2;
-        });
+        $calculator->addFunction('myfunc', static fn ($arg1, $arg2) => $arg1 + $arg2);
         $calculator->execute('myfunc(1)');
     }
 
@@ -678,9 +674,7 @@ class MathTest extends TestCase
     {
         $calculator = new MathExecutor();
         $this->expectException(IncorrectNumberOfFunctionParametersException::class);
-        $calculator->addFunction('myfunc', static function($arg1, $arg2) {
-            return $arg1 + $arg2;
-        });
+        $calculator->addFunction('myfunc', static fn ($arg1, $arg2) => $arg1 + $arg2);
         $calculator->execute('myfunc(1,2,3)');
     }
 
@@ -690,57 +684,57 @@ class MathTest extends TestCase
         $this->assertEquals(
           30,
           $calculator->execute(
-          'if(100 > 99, 30, 0)'
-        ),
+            'if(100 > 99, 30, 0)'
+          ),
           'Expression failed: if(100 > 99, 30, 0)'
         );
         $this->assertEquals(
           0,
           $calculator->execute(
-          'if(100 < 99, 30, 0)'
-        ),
+            'if(100 < 99, 30, 0)'
+          ),
           'Expression failed: if(100 < 99, 30, 0)'
         );
         $this->assertEquals(
           30,
           $calculator->execute(
-          'if(98 < 99 && sin(1) < 1, 30, 0)'
-        ),
+            'if(98 < 99 && sin(1) < 1, 30, 0)'
+          ),
           'Expression failed: if(98 < 99 && sin(1) < 1, 30, 0)'
         );
         $this->assertEquals(
           40,
           $calculator->execute(
-          'if(98 < 99 && sin(1) < 1, max(30, 40), 0)'
-        ),
+            'if(98 < 99 && sin(1) < 1, max(30, 40), 0)'
+          ),
           'Expression failed: if(98 < 99 && sin(1) < 1, max(30, 40), 0)'
         );
         $this->assertEquals(
           40,
           $calculator->execute(
-          'if(98 < 99 && sin(1) < 1, if(10 > 5, max(30, 40), 1), 0)'
-        ),
+            'if(98 < 99 && sin(1) < 1, if(10 > 5, max(30, 40), 1), 0)'
+          ),
           'Expression failed: if(98 < 99 && sin(1) < 1, if(10 > 5, max(30, 40), 1), 0)'
         );
         $this->assertEquals(
           20,
           $calculator->execute(
-          'if(98 < 99 && sin(1) > 1, if(10 > 5, max(30, 40), 1), if(4 <= 4, 20, 21))'
-        ),
+            'if(98 < 99 && sin(1) > 1, if(10 > 5, max(30, 40), 1), if(4 <= 4, 20, 21))'
+          ),
           'Expression failed: if(98 < 99 && sin(1) > 1, if(10 > 5, max(30, 40), 1), if(4 <= 4, 20, 21))'
         );
         $this->assertEquals(
           \cos(2),
           $calculator->execute(
-          'if(98 < 99 && sin(1) >= 1, max(30, 40), cos(2))'
-        ),
+            'if(98 < 99 && sin(1) >= 1, max(30, 40), cos(2))'
+          ),
           'Expression failed: if(98 < 99 && sin(1) >= 1, max(30, 40), cos(2))'
         );
         $this->assertEquals(
           \cos(2),
           $calculator->execute(
-          'if(cos(2), cos(2), 0)'
-        ),
+            'if(cos(2), cos(2), 0)'
+          ),
           'Expression failed: if(cos(2), cos(2), 0)'
         );
         $trx_amount = 100000;
@@ -749,15 +743,15 @@ class MathTest extends TestCase
         $this->assertEquals(
           $trx_amount * 0.03,
           $calculator->execute(
-          'if($trx_amount < 40000, $trx_amount * 0.06, $trx_amount * 0.03)'
-        ),
+            'if($trx_amount < 40000, $trx_amount * 0.06, $trx_amount * 0.03)'
+          ),
           'Expression failed: if($trx_amount < 40000, $trx_amount * 0.06, $trx_amount * 0.03)'
         );
         $this->assertEquals(
           $trx_amount * 0.03,
           $calculator->execute(
-          'if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
-        ),
+            'if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
+          ),
           'Expression failed: if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
         );
         $trx_amount = 39000;
@@ -765,8 +759,8 @@ class MathTest extends TestCase
         $this->assertEquals(
           $trx_amount * 0.06,
           $calculator->execute(
-          'if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
-        ),
+            'if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
+          ),
           'Expression failed: if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
         );
         $trx_amount = 59000;
@@ -774,16 +768,16 @@ class MathTest extends TestCase
         $this->assertEquals(
           $trx_amount * 0.05,
           $calculator->execute(
-          'if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
-        ),
+            'if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
+          ),
           'Expression failed: if($trx_amount < 40000, $trx_amount * 0.06, if($trx_amount < 60000, $trx_amount * 0.05, $trx_amount * 0.03))'
         );
         $this->expectException(IncorrectNumberOfFunctionParametersException::class);
         $this->assertEquals(
           0.0,
           $calculator->execute(
-          'if($trx_amount < 40000, $trx_amount * 0.06)'
-        ),
+            'if($trx_amount < 40000, $trx_amount * 0.06)'
+          ),
           'Expression failed: if($trx_amount < 40000, $trx_amount * 0.06)'
         );
     }
@@ -832,9 +826,7 @@ class MathTest extends TestCase
         $calculator = new MathExecutor();
         $calculator->addFunction(
           'round',
-          static function($value, $decimals) {
-                return \round($value, $decimals);
-            }
+          static fn ($value, $decimals) => \round($value, $decimals)
         );
         $expression = 'round(100 * 1.111111, 2)';
         $phpResult = 0;
@@ -848,9 +840,7 @@ class MathTest extends TestCase
     public function testFunctionsWithQuotes() : void
     {
         $calculator = new MathExecutor();
-        $calculator->addFunction('concat', static function($first, $second) {
-            return $first . $second;
-        });
+        $calculator->addFunction('concat', static fn ($first, $second) => $first . $second);
         $this->assertEquals('testing', $calculator->execute('concat("test", "ing")'));
         $this->assertEquals('testing', $calculator->execute("concat('test', 'ing')"));
     }
@@ -1073,14 +1063,14 @@ class MathTest extends TestCase
     /**
      * @dataProvider providerExpressionValues
      */
-    public function testCalculatingValues($expression, $value) : void
+    public function testCalculatingValues(string $expression, mixed $value) : void
     {
         $calculator = new MathExecutor();
 
         try {
             $result = $calculator->execute($expression);
         } catch (Exception $e) {
-            $this->fail(\sprintf('Exception: %s (%s:%d), expression was: %s', \get_class($e), $e->getFile(), $e->getLine(), $expression));
+            $this->fail(\sprintf('Exception: %s (%s:%d), expression was: %s', $e::class, $e->getFile(), $e->getLine(), $expression));
         }
         $this->assertEquals($value, $result, "{$expression} did not evaluate to {$value}");
     }
@@ -1091,6 +1081,8 @@ class MathTest extends TestCase
      * Most tests can go in here.  The idea is that each expression will be evaluated by MathExecutor and by PHP directly.
      * The results should be the same.  If they are not, then the test fails.  No need to add extra test unless you are doing
      * something more complex and not a simple mathmatical expression.
+     *
+     * @return array<array<mixed>>
      */
     public function providerExpressionValues()
     {