Abstract common functionality from Min and Max

This base class could also be used for other aggregate operations on
arrays, e.g. a sum. (It can't be used for `Length` though, as we would
not be able to validate a length of 0.).

Author: dmjohnsson23

library/Rules/Core/ArrayAggregateFunction.php

@@ -0,0 +1,49 @@
+<?php
+
+/*
+ * Copyright (c) Alexandre Gomes Gaigalas <alganet@gmail.com>
+ * SPDX-License-Identifier: MIT
+ */
+
+declare(strict_types=1);
+
+namespace Respect\Validation\Rules\Core;
+
+use Respect\Validation\Result;
+
+use function array_map;
+
+abstract class ArrayAggregateFunction extends FilteredNonEmptyArray
+{
+    protected string $idPrefix;
+
+    /**
+     * This function should extract the aggregate data from the input array
+     *
+     * @param non-empty-array<mixed> $input
+     */
+    abstract protected function extractAggregate(array $input): mixed;
+
+    /** @param non-empty-array<mixed> $input */
+    protected function evaluateNonEmptyArray(array $input): Result
+    {
+        $aggregate = $this->extractAggregate($input);
+
+        return $this->enrichResult($input, $this->rule->evaluate($aggregate));
+    }
+
+    private function enrichResult(mixed $input, Result $result): Result
+    {
+        if (!$result->allowsSubsequent()) {
+            return $result
+                ->withInput($input)
+                ->withChildren(
+                    ...array_map(fn(Result $child) => $this->enrichResult($input, $child), $result->children)
+                );
+        }
+
+        return (new Result($result->isValid, $input, $this, id: $result->id))
+            ->withPrefixedId($this->idPrefix)
+            ->withSubsequent($result->withInput($input));
+    }
+}

library/Rules/Max.php

@@ -11,36 +11,19 @@
 
 use Attribute;
 use Respect\Validation\Message\Template;
-use Respect\Validation\Result;
-use Respect\Validation\Rules\Core\FilteredNonEmptyArray;
+use Respect\Validation\Rules\Core\ArrayAggregateFunction;
 
-use function array_map;
 use function max;
 
 #[Attribute(Attribute::TARGET_PROPERTY | Attribute::IS_REPEATABLE)]
 #[Template('The maximum of', 'The maximum of')]
-final class Max extends FilteredNonEmptyArray
+final class Max extends ArrayAggregateFunction
 {
-    /** @param non-empty-array<mixed> $input */
-    protected function evaluateNonEmptyArray(array $input): Result
-    {
-        $max = max($input);
-
-        return $this->enrichResult($input, $this->rule->evaluate($max));
-    }
+    protected string $idPrefix = 'max';
 
-    private function enrichResult(mixed $input, Result $result): Result
+    /** @param non-empty-array<mixed> $input */
+    protected function extractAggregate(array $input): mixed
     {
-        if (!$result->allowsSubsequent()) {
-            return $result
-                ->withInput($input)
-                ->withChildren(
-                    ...array_map(fn(Result $child) => $this->enrichResult($input, $child), $result->children)
-                );
-        }
-
-        return (new Result($result->isValid, $input, $this, id: $result->id))
-            ->withPrefixedId('max')
-            ->withSubsequent($result->withInput($input));
+        return max($input);
     }
 }

library/Rules/Min.php

@@ -11,36 +11,19 @@
 
 use Attribute;
 use Respect\Validation\Message\Template;
-use Respect\Validation\Result;
-use Respect\Validation\Rules\Core\FilteredNonEmptyArray;
+use Respect\Validation\Rules\Core\ArrayAggregateFunction;
 
-use function array_map;
 use function min;
 
 #[Attribute(Attribute::TARGET_PROPERTY | Attribute::IS_REPEATABLE)]
 #[Template('The minimum of', 'The minimum of')]
-final class Min extends FilteredNonEmptyArray
+final class Min extends ArrayAggregateFunction
 {
-    /** @param non-empty-array<mixed> $input */
-    protected function evaluateNonEmptyArray(array $input): Result
-    {
-        $min = min($input);
-
-        return $this->enrichResult($input, $this->rule->evaluate($min));
-    }
+    protected string $idPrefix = 'min';
 
-    private function enrichResult(mixed $input, Result $result): Result
+    /** @param non-empty-array<mixed> $input */
+    protected function extractAggregate(array $input): mixed
     {
-        if (!$result->allowsSubsequent()) {
-            return $result
-                ->withInput($input)
-                ->withChildren(
-                    ...array_map(fn(Result $child) => $this->enrichResult($input, $child), $result->children)
-                );
-        }
-
-        return (new Result($result->isValid, $input, $this, id: $result->id))
-            ->withPrefixedId('min')
-            ->withSubsequent($result->withInput($input));
+        return min($input);
     }
 }