Redo over-zealous ncr encoding and check char limts better

Author: iMattPro

entity/rule.php

@@ -274,15 +274,15 @@ public function set_title($title)
 		// Enforce a string
 		$title = (string) $title;
 
-		// Replace four-byte UTF-8 characters before storing in utf8mb3 columns.
-		$title = utf8_encode_ucr($title);
-
-		// Limit both the displayed and stored title lengths to the column size.
-		if (truncate_string($title, 200, 200) !== $title)
+		// Enforce the public title limit before storage encoding expands characters.
+		if (truncate_string($title, 200, 2000) !== $title)
 		{
 			throw new \phpbb\boardrules\exception\unexpected_value(array('title', 'TOO_LONG'));
 		}
 
+		// MSSQL string literals cannot safely preserve every BMP character.
+		$title = strpos($this->db->get_sql_layer(), 'mssql') === 0 ? utf8_encode_ncr($title) : utf8_encode_ucr($title);
+
 		// Set the title on our data array
 		$this->data['rule_title'] = $title;
 

migrations/v30x/m21_expand_rule_title.php

@@ -0,0 +1,47 @@
+<?php
+/**
+*
+* Board Rules extension for the phpBB Forum Software package.
+*
+* @copyright (c) 2026 phpBB Limited <https://www.phpbb.com>
+* @license GNU General Public License, version 2 (GPL-2.0)
+*
+*/
+
+namespace phpbb\boardrules\migrations\v30x;
+
+class m21_expand_rule_title extends \phpbb\db\migration\migration
+{
+	/**
+	 * {@inheritdoc}
+	 */
+	public static function depends_on()
+	{
+		return array('\phpbb\boardrules\migrations\v30x\m20_unicode_language_trees');
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function update_schema()
+	{
+		return array(
+			'change_columns' => array(
+				$this->table_prefix . 'boardrules' => array(
+					'rule_title' => array('VCHAR_UNI:2000', ''),
+				),
+			),
+		);
+	}
+
+	/**
+	 * Keep the expanded column until the initial schema migration drops the table.
+	 * Reverting it could fail when encoded titles no longer fit the old size.
+	 *
+	 * @return array Array of table schema changes
+	 */
+	public function revert_schema()
+	{
+		return array();
+	}
+}

tests/entity/rule_entity_save_test.php

@@ -88,13 +88,36 @@ public function test_four_byte_title_characters_are_encoded_and_other_unicode_is
 		$this->db->sql_freeresult($result);
 
 		self::assertSame('emoji-title', $row['rule_anchor']);
-		self::assertSame('Emoji 😀 中文 Кириллица title', $row['rule_title']);
+		self::assertSame(
+			strpos($this->db->get_sql_layer(), 'mssql') === 0
+				? 'Emoji 😀 中文 Кириллица title'
+				: 'Emoji 😀 中文 Кириллица title',
+			$row['rule_title']
+		);
 
 		$entity->load(1);
 		self::assertSame('emoji-title', $entity->get_anchor());
 		self::assertSame('Emoji 😀 中文 Кириллица title', $entity->get_title());
 	}
 
+	public function test_maximum_length_unicode_title_is_preserved()
+	{
+		$title = str_repeat('К', 200);
+		$entity = $this->get_rule_entity();
+		$entity->load(1)->set_title($title)->save()->load(1);
+
+		self::assertSame($title, $entity->get_title());
+	}
+
+	public function test_expanded_ncr_storage_is_preserved()
+	{
+		$title = str_repeat('😀', 200);
+		$entity = $this->get_rule_entity();
+		$entity->load(1)->set_title($title)->save()->load(1);
+
+		self::assertSame($title, $entity->get_title());
+	}
+
 	/**
 	* Test saving to (non-existant) rules from the database
 	*

tests/entity/rule_entity_title_test.php

@@ -38,6 +38,10 @@ public function title_test_data()
 				str_repeat('К', 200),
 				str_repeat('К', 200),
 			),
+			array(
+				str_repeat('a', 194) . '&&',
+				str_repeat('a', 194) . '&&',
+			),
 		);
 	}
 
@@ -75,11 +79,6 @@ public function title_fails_test_data()
 			array(
 				str_repeat('a', 201),
 			),
-
-			// Escaped request value exceeds the stored column length.
-			array(
-				str_repeat('a', 194) . '&&',
-			),
 		);
 	}
 

tests/functional/admin_controller_test.php

@@ -167,7 +167,9 @@ public function test_acp_create_rule($crawler)
 		$stored_title = $this->db->sql_fetchfield('rule_title', false, $result);
 		$this->db->sql_freeresult($result);
 
-		$expected_title = 'Test 😀 中文 Кириллица Rule';
+		$expected_title = strpos($this->db->get_sql_layer(), 'mssql') === 0
+			? 'Test 😀 中文 Кириллица Rule'
+			: 'Test 😀 中文 Кириллица Rule';
 		self::assertSame($expected_title, $stored_title);
 		self::assertSame($rule_title, utf8_decode_ncr($stored_title));
 	}