Split ChangeTags::modifyDisplayQuery() to two smaller functions

This would be useful for replacing cases of tag_summary

Bug: T209525
Change-Id: If0c949fe190934fe5318d9c5ff9dfb13d52adc56

diff --git a/includes/changetags/ChangeTags.php b/includes/changetags/ChangeTags.php
index 0e36009..c6e8e1f 100644 (file)
--- a/includes/changetags/ChangeTags.php
+++ b/includes/changetags/ChangeTags.php
@@ -788,7 +788,7 @@ class ChangeTags {
        public static function modifyDisplayQuery( &$tables, &$fields, &$conds,
                &$join_conds, &$options, $filter_tag = ''
        ) {
-               global $wgUseTagFilter, $wgChangeTagsSchemaMigrationStage;
+               global $wgChangeTagsSchemaMigrationStage, $wgUseTagFilter;
 
                // Normalize to arrays
                $tables = (array)$tables;
@@ -796,6 +796,8 @@ class ChangeTags {
                $conds = (array)$conds;
                $options = (array)$options;
 
+               $fields['ts_tags'] = self::makeTagSummarySubquery( $tables );
+
                // Figure out which ID field to use
                if ( in_array( 'recentchanges', $tables ) ) {
                        $join_cond = 'ct_rc_id=rc_id';
@@ -809,20 +811,6 @@ class ChangeTags {
                        throw new MWException( 'Unable to determine appropriate JOIN condition for tagging.' );
                }
 
-               $tagTables[] = 'change_tag';
-               if ( $wgChangeTagsSchemaMigrationStage > MIGRATION_WRITE_BOTH ) {
-                       $tagTables[] = 'change_tag_def';
-                       $join_cond_ts_tags = [ 'change_tag_def' => [ 'INNER JOIN', 'ct_tag_id=ctd_id' ] ];
-                       $field = 'ctd_name';
-               } else {
-                       $field = 'ct_tag';
-                       $join_cond_ts_tags = [];
-               }
-
-               $fields['ts_tags'] = wfGetDB( DB_REPLICA )->buildGroupConcatField(
-                       ',', $tagTables, $field, $join_cond, $join_cond_ts_tags
-               );
-
                if ( $wgUseTagFilter && $filter_tag ) {
                        // Somebody wants to filter on a tag.
                        // Add an INNER JOIN on change_tag
@@ -858,6 +846,48 @@ class ChangeTags {
                }
        }
 
+       /**
+        * Make the tag summary subquery based on the given tables and return it.
+        *
+        * @param string|array $tables Table names, see Database::select
+        *
+        * @return string tag summary subqeury
+        * @throws MWException When unable to determine appropriate JOIN condition for tagging
+        */
+       public static function makeTagSummarySubquery( $tables ) {
+               global $wgChangeTagsSchemaMigrationStage;
+
+               // Normalize to arrays
+               $tables = (array)$tables;
+
+               // Figure out which ID field to use
+               if ( in_array( 'recentchanges', $tables ) ) {
+                       $join_cond = 'ct_rc_id=rc_id';
+               } elseif ( in_array( 'logging', $tables ) ) {
+                       $join_cond = 'ct_log_id=log_id';
+               } elseif ( in_array( 'revision', $tables ) ) {
+                       $join_cond = 'ct_rev_id=rev_id';
+               } elseif ( in_array( 'archive', $tables ) ) {
+                       $join_cond = 'ct_rev_id=ar_rev_id';
+               } else {
+                       throw new MWException( 'Unable to determine appropriate JOIN condition for tagging.' );
+               }
+
+               $tagTables[] = 'change_tag';
+               if ( $wgChangeTagsSchemaMigrationStage > MIGRATION_WRITE_BOTH ) {
+                       $tagTables[] = 'change_tag_def';
+                       $join_cond_ts_tags = [ 'change_tag_def' => [ 'INNER JOIN', 'ct_tag_id=ctd_id' ] ];
+                       $field = 'ctd_name';
+               } else {
+                       $field = 'ct_tag';
+                       $join_cond_ts_tags = [];
+               }
+
+               return wfGetDB( DB_REPLICA )->buildGroupConcatField(
+                       ',', $tagTables, $field, $join_cond, $join_cond_ts_tags
+               );
+       }
+
        /**
         * Build a text box to select a change tag
         *