Optimize constant usage

Instead of defining constants with the same name and values at different
 namespaces, they're now defined at an interface which can be shared
among classes by implementing this interface.

lib/jblond/Diff.php

@@ -5,6 +5,7 @@
 namespace jblond;
 
 use InvalidArgumentException;
+use jblond\Diff\ConstantsInterface;
 use jblond\Diff\SequenceMatcher;
 use jblond\Diff\Similarity;
 use OutOfRangeException;
@@ -26,20 +27,8 @@
  * @version         2.3.0
  * @link            https://github.com/JBlond/php-diff
  */
-class Diff
+class Diff implements ConstantsInterface
 {
-    /**
-     * Flag to disable ignore of successive empty/blank lines.
-     */
-    public const DIFF_IGNORE_LINE_NONE = 0;
-    /**
-     * Flag to ignore successive empty lines.
-     */
-    public const DIFF_IGNORE_LINE_EMPTY = 1;
-    /**
-     * Flag to ignore successive blank lines. (Lines which contain no or only non printable characters.)
-     */
-    public const DIFF_IGNORE_LINE_BLANK = 2;
     /**
      * @var array   The first version to compare.
      *              Each element contains a line of this string.

lib/jblond/Diff/ConstantsInterface.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace jblond\Diff;
+/**
+ * Constant Interface
+ *
+ * Defines the library constants which needs to be shared across the different classes.
+ *
+ * PHP version 7.2 or greater
+ *
+ * @package         jblond
+ * @author          Ferry Cools <[email protected]>
+ * @copyright   (c) 2020 Mario Brandt
+ * @license         New BSD License http://www.opensource.org/licenses/bsd-license.php
+ * @version         2.3.0
+ * @link            https://github.com/JBlond/php-diff
+ */
+interface ConstantsInterface
+{
+    /**
+     * Flag to disable ignore of successive empty/blank lines.
+     */
+    public const DIFF_IGNORE_LINE_NONE = 0;
+    /**
+     * Flag to ignore empty lines.
+     */
+    public const DIFF_IGNORE_LINE_EMPTY = 1;
+    /**
+     * Flag to ignore blank lines. (Lines which contain no or only non printable characters.)
+     */
+    public const DIFF_IGNORE_LINE_BLANK = 2;
+
+}

lib/jblond/Diff/SequenceMatcher.php

@@ -20,20 +20,8 @@
  * @version         2.3.0
  * @link            https://github.com/JBlond/php-diff
  */
-class SequenceMatcher
+class SequenceMatcher implements ConstantsInterface
 {
-    /**
-     * Flag to disable ignore of successive empty/blank lines.
-     */
-    public const DIFF_IGNORE_LINE_NONE = 0;
-    /**
-     * Flag to ignore empty lines.
-     */
-    public const DIFF_IGNORE_LINE_EMPTY = 1;
-    /**
-     * Flag to ignore blank lines. (Lines which contain no or only non printable characters.)
-     */
-    public const DIFF_IGNORE_LINE_BLANK = 2;
     /**
      * @var array The first sequence to compare against.
      */
@@ -360,12 +348,18 @@ public function getOpCodes(): array
                 $part2 = array_slice($this->new, $j, $bj - $j);
 
                 if ($this->options['ignoreLines'] == 2) {
-                    array_walk($part1, function (&$line) {
-                        $line = trim($line);
-                    });
-                    array_walk($part2, function (&$line) {
-                        $line = trim($line);
-                    });
+                    array_walk(
+                        $part1,
+                        function (&$line) {
+                            $line = trim($line);
+                        }
+                    );
+                    array_walk(
+                        $part2,
+                        function (&$line) {
+                            $line = trim($line);
+                        }
+                    );
                     unset($line);
                 }