mail: Refactor checks looking for PEAR libraries to be clearer

I don't think this makes any difference towards the linked bug, but
it makes it more obvious that MediaWiki doesn't try to use any PEAR
classes before attempting to require them.

Bug: T186456
Change-Id: I342f41903a15f13e72e76464499351412a9afa34

diff --git a/includes/mail/UserMailer.php b/includes/mail/UserMailer.php
index fb0f2f9..7b48ad0 100644 (file)
--- a/includes/mail/UserMailer.php
+++ b/includes/mail/UserMailer.php
@@ -189,6 +189,46 @@ class UserMailer {
                return self::sendInternal( $to, $from, $subject, $body, $options );
        }
 
+       /**
+        * Whether the PEAR Mail_mime library is usable. This will
+        * try and load it if it is not already.
+        *
+        * @return bool
+        */
+       private static function isMailMimeUsable() {
+               static $usable = null;
+               if ( $usable === null ) {
+                       // If the class is not already loaded, and it's in the include path,
+                       // try requiring it.
+                       if ( !class_exists( 'Mail_mime' ) && stream_resolve_include_path( 'Mail/mime.php' ) ) {
+                               require_once 'Mail/mime.php';
+                       }
+                       $usable = class_exists( 'Mail_mime' );
+               }
+
+               return $usable;
+       }
+
+       /**
+        * Whether the PEAR Mail library is usable. This will
+        * try and load it if it is not already.
+        *
+        * @return bool
+        */
+       private static function isMailUsable() {
+               static $usable = null;
+               if ( $usable === null ) {
+                       // If the class is not already loaded, and it's in the include path,
+                       // try requiring it.
+                       if ( !class_exists( 'Mail' ) && stream_resolve_include_path( 'Mail.php' ) ) {
+                               require_once 'Mail.php';
+                       }
+                       $usable = class_exists( 'Mail' );
+               }
+
+               return $usable;
+       }
+
        /**
         * Helper function fo UserMailer::send() which does the actual sending. It expects a $to
         * list which the UserMailerSplitTo hook would not split further.
@@ -296,15 +336,12 @@ class UserMailer {
                if ( is_array( $body ) ) {
                        // we are sending a multipart message
                        wfDebug( "Assembling multipart mime email\n" );
-                       if ( !stream_resolve_include_path( 'Mail/mime.php' ) ) {
+                       if ( !self::isMailMimeUsable() ) {
                                wfDebug( "PEAR Mail_Mime package is not installed. Falling back to text email.\n" );
                                // remove the html body for text email fall back
                                $body = $body['text'];
                        } else {
-                               // Check if pear/mail_mime is already loaded (via composer)
-                               if ( !class_exists( 'Mail_mime' ) ) {
-                                       require_once 'Mail/mime.php';
-                               }
+                               // pear/mail_mime is already loaded by this point
                                if ( wfIsWindows() ) {
                                        $body['text'] = str_replace( "\n", "\r\n", $body['text'] );
                                        $body['html'] = str_replace( "\n", "\r\n", $body['html'] );
@@ -352,12 +389,8 @@ class UserMailer {
 
                if ( is_array( $wgSMTP ) ) {
                        // Check if pear/mail is already loaded (via composer)
-                       if ( !class_exists( 'Mail' ) ) {
-                               // PEAR MAILER
-                               if ( !stream_resolve_include_path( 'Mail.php' ) ) {
-                                       throw new MWException( 'PEAR mail package is not installed' );
-                               }
-                               require_once 'Mail.php';
+                       if ( !self::isMailUsable() ) {
+                               throw new MWException( 'PEAR mail package is not installed' );
                        }
 
                        Wikimedia\suppressWarnings();