added Helpers::getSuggestion()

Author: dg

src/Utils/Helpers.php

@@ -35,4 +35,22 @@ public static function falseToNull($val)
 	{
 		return $val === false ? null : $val;
 	}
+
+
+	/**
+	 * Finds the best suggestion (for 8-bit encoding).
+	 * @param  string[]  $possibilities
+	 */
+	public static function getSuggestion(array $possibilities, string $value): ?string
+	{
+		$best = null;
+		$min = (strlen($value) / 4 + 1) * 10 + .1;
+		foreach (array_unique($possibilities) as $item) {
+			if ($item !== $value && ($len = levenshtein($item, $value, 10, 11, 10)) < $min) {
+				$min = $len;
+				$best = $item;
+			}
+		}
+		return $best;
+	}
 }

tests/Utils/Helpers.getSuggestion().phpt

@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+use Nette\Utils\Helpers;
+use Tester\Assert;
+
+
+require __DIR__ . '/../bootstrap.php';
+
+
+Assert::same(null, Helpers::getSuggestion([], ''));
+Assert::same(null, Helpers::getSuggestion([], 'a'));
+Assert::same(null, Helpers::getSuggestion(['a'], 'a'));
+Assert::same('a', Helpers::getSuggestion(['a', 'b'], ''));
+Assert::same('b', Helpers::getSuggestion(['a', 'b'], 'a')); // ignore 100% match
+Assert::same('a1', Helpers::getSuggestion(['a1', 'a2'], 'a')); // take first
+Assert::same(null, Helpers::getSuggestion(['aaa', 'bbb'], 'a'));
+Assert::same(null, Helpers::getSuggestion(['aaa', 'bbb'], 'ab'));
+Assert::same(null, Helpers::getSuggestion(['aaa', 'bbb'], 'abc'));
+Assert::same('bar', Helpers::getSuggestion(['foo', 'bar', 'baz'], 'baz'));
+Assert::same('abcd', Helpers::getSuggestion(['abcd'], 'acbd'));
+Assert::same('abcd', Helpers::getSuggestion(['abcd'], 'axbd'));
+Assert::same(null, Helpers::getSuggestion(['abcd'], 'axyd')); // 'tags' vs 'this'
+Assert::same(null, Helpers::getSuggestion(['setItem'], 'item'));