localisation: Make PHP cache files slimmer

The only difference is the scalar values are no longer encoded as an
array, but just the value itself. As a result, PHP localisation cache
files are about 2/3rds of their previous size and become slightly
smaller than CDB files.

Bug: T99740
Change-Id: Iaa5e32830dc1bb710b9e0f1a681afe91e521ece9

diff --git a/includes/cache/localisation/LCStoreStaticArray.php b/includes/cache/localisation/LCStoreStaticArray.php
index c5a2512..75c8465 100644 (file)
--- a/includes/cache/localisation/LCStoreStaticArray.php
+++ b/includes/cache/localisation/LCStoreStaticArray.php
@@ -68,21 +68,21 @@ class LCStoreStaticArray implements LCStore {
         * Encodes a value into an array format
         *
         * @param mixed $value
-        * @return array
+        * @return array|mixed
         * @throws RuntimeException
         */
        public static function encode( $value ) {
-               if ( is_scalar( $value ) || $value === null ) {
-                       // [V]alue
-                       return [ 'v', $value ];
+               if ( is_array( $value ) ) {
+                       // [a]rray
+                       return [ 'a', array_map( 'LCStoreStaticArray::encode', $value ) ];
                }
                if ( is_object( $value ) ) {
-                       // [S]erialized
+                       // [s]erialized
                        return [ 's', serialize( $value ) ];
                }
-               if ( is_array( $value ) ) {
-                       // [A]rray
-                       return [ 'a', array_map( 'LCStoreStaticArray::encode', $value ) ];
+               if ( is_scalar( $value ) || $value === null ) {
+                       // Scalar value, written directly without array
+                       return $value;
                }
 
                throw new RuntimeException( 'Cannot encode ' . var_export( $value, true ) );
@@ -91,21 +91,28 @@ class LCStoreStaticArray implements LCStore {
        /**
         * Decode something that was encoded with encode
         *
-        * @param array $encoded
+        * @param mixed $encoded
         * @return array|mixed
         * @throws RuntimeException
         */
-       public static function decode( array $encoded ) {
+       public static function decode( $encoded ) {
+               if ( !is_array( $encoded ) ) {
+                       // Scalar values are written directly without array
+                       return $encoded;
+               }
+
                $type = $encoded[0];
                $data = $encoded[1];
 
                switch ( $type ) {
-                       case 'v':
-                               return $data;
-                       case 's':
-                               return unserialize( $data );
                        case 'a':
                                return array_map( 'LCStoreStaticArray::decode', $data );
+                       case 's':
+                               return unserialize( $data );
+                       case 'v':
+                               // Support: MediaWiki 1.32 and earlier
+                               // Backward compatibility with older file format
+                               return $data;
                        default:
                                throw new RuntimeException(
                                        'Unable to decode ' . var_export( $encoded, true ) );