Changeset 61857

Timestamp:

03/06/2026 08:04:31 PM (7 months ago)

Author:

dmsnell

Message:

Functions: Memoize wp_normalize_path().

wp_normalize_path() is called thousands of times on a given request. This patch adds memoization via a function-local static variable. This reduces the call count to the underlying wp_is_stream() function, and measured in testing around a 66% cache hit rate.

In testing, for a site making 4000 calls to wp_normalize_path(), this patch led to a reduction in runtime from 1.4 ms to 0.4 ms on the test computer. While small, this time occurs early in the hotpath of the loading WordPress.

Developed in: ​https://github.com/WordPress/wordpress-develop/pull/10770
Discussed in: https://core.trac.wordpress.org/ticket/64538

Props dmsnell, josephscott, mreishus, westonruter.
Fixes #64538.

Location:

trunk

Files:

• src/wp-includes/functions.php (modified) (3 diffs)
• tests/phpunit/tests/functions.php (modified) (1 diff)

trunk/src/wp-includes/functions.php

@@ -2180 +2180 @@
  * @since 4.5.0 Allows for Windows network shares.
  * @since 4.9.7 Allows for PHP file wrappers.
+ * @since 7.0.0 Uses a static cache to store normalized paths.
  *
  * @param string $path Path to normalize.
  * @return string Normalized path.
  */
-function wp_normalize_path( $path ) {
-        $wrapper = '';
+function wp_normalize_path( $path ): string {
+        $path = (string) $path;
+
+        static $cache = array();
+        if ( isset( $cache[ $path ] ) ) {
+                return $cache[ $path ];
+        }
+
+        $original_path = $path;
+        $wrapper       = '';
 
         if ( wp_is_stream( $path ) ) {
@@ -2197 +2206 @@
 
         // Replace multiple slashes down to a singular, allowing for network shares having two slashes.
-        $path = preg_replace( '|(?<=.)/+|', '/', $path );
+        $path = (string) preg_replace( '|(?<=.)/+|', '/', $path );
 
         // Windows paths should uppercase the drive letter.
@@ -2204 +2213 @@
         }
 
-        return $wrapper . $path;
+        $cache[ $original_path ] = $wrapper . $path;
+        return $cache[ $original_path ];
 }
 

trunk/tests/phpunit/tests/functions.php

@@ -223 +223 @@
                         array( 'http://example.com//path.ext', 'http://example.com/path.ext' ),
                         array( 'file://c:\\www\\path\\', 'file://C:/www/path/' ),
-                );
+
+                        // Edge cases.
+                        array( '', '' ), // Empty string should return empty string.
+                        array( 123, '123' ), // Integer should be cast to string.
+                );
+        }
+
+        /**
+         * Tests that wp_normalize_path() works with objects that have __toString().
+         *
+         * This is important because the function uses a static cache, and the input
+         * must be cast to string before being used as an array key.
+         *
+         * @ticket 64538
+         */
+        public function test_wp_normalize_path_with_stringable_object() {
+                $file_info = new SplFileInfo( '/var/www/html\\test' );
+
+                $this->assertSame( '/var/www/html/test', wp_normalize_path( $file_info ) );
+        }
+
+        /**
+         * Tests that wp_normalize_path() returns consistent results on repeated calls.
+         *
+         * The function uses a static cache, so this verifies cache behavior.
+         *
+         * @ticket 64538
+         */
+        public function test_wp_normalize_path_returns_consistent_results() {
+                $path = 'C:\\www\\path\\';
+
+                $first_call  = wp_normalize_path( $path );
+                $second_call = wp_normalize_path( $path );
+                $third_call  = wp_normalize_path( $path );
+
+                $this->assertSame( $first_call, $second_call, 'Second call should return same result as first.' );
+                $this->assertSame( $second_call, $third_call, 'Third call should return same result as second.' );
+                $this->assertSame( 'C:/www/path/', $first_call, 'Normalized path should match expected value.' );
+        }
+
+        /**
+         * Tests that wp_normalize_path() static cache stores results.
+         *
+         * @ticket 64538
+         */
+        public function test_wp_normalize_path_static_cache() {
+                $path     = '/var/www/cache-test\\subdir\\';
+                $expected = '/var/www/cache-test/subdir/';
+
+                $result = wp_normalize_path( $path );
+                $this->assertSame( $expected, $result );
+
+                $reflection  = new ReflectionFunction( 'wp_normalize_path' );
+                $static_vars = $reflection->getStaticVariables();
+
+                $this->assertArrayHasKey( 'cache', $static_vars, 'Static cache array should exist.' );
+                $this->assertArrayHasKey( $path, $static_vars['cache'], 'Cache should contain the normalized path.' );
+                $this->assertSame( $expected, $static_vars['cache'][ $path ], 'Cached value should match the expected normalized path.' );
         }