Update test code using from KEINOS/mb_levenshtein

A userland function to compare multiple code points.
We uses that code for test code.

Author: youkidearitai

ext/mbstring/tests/mb_levenshtein.phpt

@@ -4,7 +4,7 @@ mb_levenshtein() function test
 mbstring
 --FILE--
 <?php
-
+require_once("mb_levenshtein_userland.inc");
 echo '--- Equal ---' . \PHP_EOL;
 var_dump(mb_levenshtein('12345', '12345'));
 
@@ -57,43 +57,15 @@ $cafe = mb_convert_encoding("café", "ISO-8859-1", "UTF-8");
 var_dump(mb_levenshtein("cafe", $cafe, encoding: "ISO-8859-1"));
 
 echo '--- Usecase of userland code ---' . \PHP_EOL;
-/* from: https://qiita.com/mpyw/items/2b636827730e06c71e3d */
-$query = 'ほあようごぁいまーしゅ';
-$comps = [
-	'こんにちはー',
-	'おはようございまーす',
-	'こんばんはー',
-	'おやすみなさーい',
-	'いただきまーす',
-	'おつかれさまー',
-	'ぬぁあああんつかれたもぉぉぉぉぉぉん',
-];
-$min = 99999;
-$min_key = 0;
-foreach ($comps as $key => $comp) {
-	$sim = mb_levenshtein($query, $comp);
-	if ($min >= $sim) {
-		$min = $sim;
-		$min_key = $key;
-	}
-}
-var_dump($comps[$min_key]);
 
-$base = 'やんほぬ';
-$comps = [
-	'かんのみほ',
-	'かんのみほう',
-	'かんぺみろ',
-	'ああいいふろ',
-	'ちゃんとみろ',
-	'ターミナルさん',
-];
-foreach ($comps as $comp) {
-	var_dump(mb_levenshtein($base, $comp));
+for ($i = 0; $i < 100; $i++) {
+	$bytes = implode("", array_map(function ($byte) { return mb_chr(intval(bin2hex($byte), 16), "UTF-8"); }, str_split(random_bytes(10))));
+	$compare = "あいうえおABCDEF";
+	if (mb_levenshtein($bytes, $compare) !== keinos_mb_levenshtein($bytes, $compare)) {
+		throw Exception("mb_levenshtein compare error: {$bytes}");
+	}
 }
-
-/* from: https://qiita.com/suin/items/a0a8227addad11ff2ea7 */
-var_dump(mb_levenshtein('あとうかい', 'かとうあい')); // int(2)
+echo "OK" . PHP_EOL;
 ?>
 --EXPECT--
 --- Equal ---
@@ -136,11 +108,4 @@ int(2)
 --- café in ISO-8859-1 ---
 int(1)
 --- Usecase of userland code ---
-string(30) "おはようございまーす"
-int(4)
-int(4)
-int(4)
-int(6)
-int(5)
-int(7)
-int(2)
+OK

ext/mbstring/tests/mb_levenshtein_userland.inc

@@ -0,0 +1,88 @@
+<?php
+/* from: https://github.com/KEINOS/mb_levenshtein/blob/master/mb_levenshtein.php
+ * MIT License
+ * 
+ * Copyright (c) 2021 KEINOS and the contributors (https://git.io/J9Gmd)
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+/**
+ * mb_levenshtein.
+ *
+ * Didactic example showing the usage of the previous conversion function.
+ * But for better performance, in a real application with a single input string
+ * matched against many strings from a database, you will probably want to pre-
+ * encode the input only once.
+ *
+ * @param  string  $s1        One of the strings being evaluated for Levenshtein distance.
+ * @param  string  $s2        One of the strings being evaluated for Levenshtein distance.
+ * @param  integer $cost_ins  Defines the cost of insertion.
+ * @param  integer $cost_rep  Defines the cost of replacement.
+ * @param  integer $cost_del  Defines the cost of deletion.
+ *
+ * @return integer
+ */
+function keinos_mb_levenshtein($s1, $s2, $cost_ins = 1, $cost_rep = 1, $cost_del = 1)
+{
+	$charMap = array();
+	convert_mb_ascii($s1, $charMap);
+	convert_mb_ascii($s2, $charMap);
+
+	return levenshtein($s1, $s2, $cost_ins, $cost_rep, $cost_del);
+}
+
+/**
+ * convert_mb_ascii.
+ *
+ * Convert an UTF-8 encoded string to a single-byte string suitable for
+ * functions such as levenshtein.
+ *
+ * The function simply uses (and updates) a tailored dynamic encoding
+ * (in/out map parameter) where non-ascii characters are remapped to
+ * the range [128-255] in order of appearance.
+ *
+ * Thus it supports up to 128 different multibyte code points max over
+ * the whole set of strings sharing this encoding.
+ *
+ * @param  string $str  UTF-8 string to be converted to extended ASCII.
+ * @param  array  $map  Reference of the map.
+ *
+ * @return void
+ */
+function convert_mb_ascii(&$str, &$map)
+{
+	// find all utf-8 characters
+	$matches = array();
+	if (! preg_match_all('/[\xC0-\xF7][\x80-\xBF]+/', $str, $matches)) {
+		return; // plain ascii string
+	}
+
+	// update the encoding map with the characters not already met
+	$mapCount = count($map);
+	foreach ($matches[0] as $mbc) {
+		if (! isset($map[$mbc])) {
+			$map[$mbc] = chr(128 + $mapCount);
+			$mapCount++;
+		}
+	}
+
+	// finally remap non-ascii characters
+	$str = strtr($str, $map);
+}
+