Fix output issue with PHP >= 7.3.

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tablepress-rowspan-all.php

@@ -2,7 +2,7 @@
 /*
 Plugin Name: TablePress Extension: Rowspans everywhere
 Description: Allows using rowspans in thead.
-Version: 1.1.0
+Version: 1.2.0
 Author: strarsis <[email protected]>
 GitHub Plugin URI: strarsis/tablepress-rowspan-all
 */
@@ -13,120 +13,128 @@
 const TABLEPRESS_ROWSPAN_OUTSIDE = '#outside_rowspan#';
 
 
-// change trigger words in table header to preserve them
-// (TablePress already uses #rowspan# but only between body cells, not table head + body cells)
-add_filter('tablepress_table_raw_render_data', function($table, $render_options)
-{
-
+// Replace #rowspan# trigger word in table header (thead) cells with something else to preserve them 
+// as they would be, although ignored by TablePress, they are still cleaned up by it
+// @see https://github.com/TobiasBg/TablePress/blob/master/classes/class-render.php#L53
+// (TablePress already uses #rowspan# but only between table body cells, it ignores it between table header and body cells)
+function tablepress_ext_rowspan_all_trigger_words($table, $render_options) {
+    // $table is a nested array
+
     // rows
     $rows = $table['data'];
-    
+
     // more than two row for thead + potential rowspan making sense at all
     if (count($rows) <= 1)
         return $table; // skip
-    
+
     // with a tfoot, there must be at least three rows (header, middle, footer)
     if ($render_options['table_head'] && (!$render_options['table_foot'] || $render_options['table_foot'] && count($rows) <= 2)) {
-        
+
         $last_row_no = 0;
         for ($row_no = 1; $row_no < count($rows); $row_no++) {
             $row = $rows[$row_no];
-            
+
             for ($col_no = 0; $col_no < count($row); $col_no++) {
                 $col = $row[$col_no];
-                
+
                 // only continous rows after head
                 if ($col === TABLEPRESS_ROWSPAN) {
                     if ($row_no > ($last_row_no + 1))
                         return $table; // skip table
-                    
+
                     $last_row_no = $row_no;
-                    
+
                     $table['data'][$row_no][$col_no] = TABLEPRESS_ROWSPAN_OUTSIDE;
                 }
-                
+
             }
-            
+
         }
-        
+
     }
-
     return $table;
-}, 10, 2);
+}
+add_filter('tablepress_table_raw_render_data', 'tablepress_ext_rowspan_all_trigger_words', 10, 2);
 
-add_filter('tablepress_table_output', function($output, $table, $render_options)
-{
+
+// Add rowspan-attributes to table header cells in rendered HTML output
+// TablePress-specific assumptions:
+// - There is only one row (<tr></tr>) in table header (<thead></thead>).
+function tablepress_ext_rowspan_all_adjust_html($output, $table, $render_options) {
     // table
     $table = fragment_to_dom($output);
     $dom   = $table->ownerDocument;
     $xpath = new DOMXpath($dom);
-
-    // tablepress-specific assumptions:
-    // - there is only one row (<tr></tr>) in table header (<thead></thead>)
-
+
     // thead
     $theads = $xpath->query('//thead');
     if ($theads->length === 0)
         return $output; // skip
     $thead = $theads->item(0);
-    
+
     $thead_row   = $thead->getElementsByTagName('tr')->item(0);
     $thead_cells = $thead_row->getElementsByTagName('th');
-    
-    // thead cells can also have colspan
-    // physical occupation map
+
+
+    // thead cells can also have colspans
     $thead_cells_phys = array();
     foreach ($thead_cells as $thead_cell_index => $thead_cell) {
-        $thead_cells_phys[] = $thead_cell_index; // add at least once
-
-        $thead_cell_colspan = $thead_cell->getAttribute('colspan');
-        if (empty($thead_cell_colspan))
-            continue; // skip cell
-        for ($cs = 0; $cs < ($thead_cell_colspan - 1); $cs++)
-            $thead_cells_phys[] = $thead_cell_index;
+        $colspan_val = $thead_cell->getAttribute('colspan');
+        $colspan     = !empty($colspan_val) ? $colspan_val : 1; // default colspan = 1
+
+        for($ins_col = 0; $ins_col < $colspan; $ins_col++)
+            $thead_cells_phys[] = $thead_cell_index - 1; // 0-based index!
     }
-
-    // all rowspan marked cells
-    $trigger_cells = $xpath->query(".//td[not(ancestor::thead) and " . "not(ancestor::tfoot) and " . "text() = '" . TABLEPRESS_ROWSPAN_OUTSIDE . "']");
-
+
+
+    // all cells in table body that contain the outside-rowspan trigger word text,
+    // sorted by their order in DOM, row order is preserved
+    $trigger_cells = $xpath->query(".//td[not(ancestor::thead) and not(ancestor::tfoot) and text() = '" . TABLEPRESS_ROWSPAN_OUTSIDE . "']");
+
     $last_row_no = 0;
     foreach ($trigger_cells as $cell) {
         // row of cell
         $row = $xpath->query('parent::tr', $cell)->item(0);
-        
+
         // only continous rows after head (2nd test)
         $row_no = dom_parent_position($row);
-        if ($row_no > ($last_row_no + 1))
+        if ($row_no > ($last_row_no + 1)) // when more than one row is skipped
             continue;
         $last_row_no = $row_no;
-        
-        // find thead cell above this cell
-        $cell_no            = dom_parent_position($cell);
+
+        // find thead cell above this cell (in same physical column)
+        $cell_no            = dom_parent_position($cell); // cell no = column no
         $thead_cell_phys_no = $thead_cells_phys[$cell_no];
         $thead_cell         = $thead_cells->item($thead_cell_phys_no);
-
-        // update rowspan of cell
-        $cur_rowspan = $thead_cell->getAttribute('rowspan');
-        if (!$cur_rowspan)
-            $cur_rowspan = 1;
-
+
+        // update rowspan of thead cell
+        $cur_rowspan_val = $thead_cell->getAttribute('rowspan');
+        $cur_rowspan     = !empty($cur_rowspan_val) ? $cur_rowspan_val : 1; // default rowspan = 1
+
         $thead_cell->setAttribute('rowspan', $cur_rowspan + 1);
-
-        // move row to thead
-        $thead->appendChild($row);
     }
-
-    // remove the placeholder trigger word cells
-    // in second step because removal during iteration causes issues
-    foreach ($trigger_cells as $cell)
+
+
+    // The following manipulations change the DOM tree,
+    // this would intefere in the loop above, 
+    // hence this is done in a separate step afterwards:
+
+    foreach ($trigger_cells as $cell) {
+        // move affected rows to thead
+        $row = $xpath->query('parent::tr', $cell)->item(0);
+        $thead->appendChild($row); // (idempotent)
+
+        // remove the placeholder trigger word cells
         $cell->parentNode->removeChild($cell);
-
+    }
+
     // change td to th for the new row
     $thead_td_cells = $xpath->query('.//td', $thead);
     foreach ($thead_td_cells as $td_cell)
         $changed_th_cell = dom_change_tagname($td_cell, 'th');
-    
-    
+
+
     $newHtml = dom_to_fragment($table);
     return $newHtml;
-}, 3, 10);
+}
+add_filter('tablepress_table_output', 'tablepress_ext_rowspan_all_adjust_html', 3, 10);