Ticket #15386: 15386.diff

src/wp-admin/includes/screen.php

@@ -10 +10 @@
  * Get the column headers for a screen
  *
  * @since 2.7.0
- *
- * @staticvar array $column_headers
+ * @since 5.5.0 Removed a static var that made it difficult to instantiate list
+ *              tables after the page header had been rendered.
  *
  * @param string|WP_Screen $screen The screen you want the headers for
  * @return string[] The column header labels keyed by column ID.
@@ -21 +21 @@
                 $screen = convert_to_screen( $screen );
         }
 
-        static $column_headers = array();
-
-        if ( ! isset( $column_headers[ $screen->id ] ) ) {
-                /**
-                 * Filters the column headers for a list table on a specific screen.
-                 *
-                 * The dynamic portion of the hook name, `$screen->id`, refers to the
-                 * ID of a specific screen. For example, the screen ID for the Posts
-                 * list table is edit-post, so the filter for that screen would be
-                 * manage_edit-post_columns.
-                 *
-                 * @since 3.0.0
-                 *
-                 * @param string[] $columns The column header labels keyed by column ID.
-                 */
-                $column_headers[ $screen->id ] = apply_filters( "manage_{$screen->id}_columns", array() );
-        }
-
-        return $column_headers[ $screen->id ];
+        /**
+         * Filters the column headers for a list table on a specific screen.
+         *
+         * The dynamic portion of the hook name, `$screen->id`, refers to the
+         * ID of a specific screen. For example, the screen ID for the Posts
+         * list table is edit-post, so the filter for that screen would be
+         * manage_edit-post_columns.
+         *
+         * @since 3.0.0
+         *
+         * @param string[] $columns The column header labels keyed by column ID.
+         */
+        return apply_filters( "manage_{$screen->id}_columns", array() );
 }
 
 /**

tests/phpunit/tests/admin/includesListTable.php

@@ -293 +293 @@
 
                 $this->assertNotContains( 'id="delete_all"', $output );
         }
+
+        /**
+         * Test that can a list can display with no dependency on core screen context.
+         *
+         * @ticket 15386
+         */
+        public function test_table_list_renders() {
+                $table = _get_list_table( 'WP_Comments_List_Table', array( 'screen' => 'my-plugin-page' ) );
+
+                // At least one comment needed.
+                $this->factory->comment->create_many( 10 );
+
+                ob_start();
+
+                $table->views();
+                $table->prepare_items();
+                $table->display();
+                $output = ob_get_clean();
+
+                // CSS class only exists if the table has at least one comment.
+                $this->assertContains( 'class="submitted-on"', $output );
+        }
 }