Table name is now case insensitive

Table name comparison changed to UTF-8 aware and case insensitive

src/PhpSpreadsheet/Worksheet/Table.php

@@ -4,6 +4,7 @@ namespace PhpOffice\PhpSpreadsheet\Worksheet;
 
 use PhpOffice\PhpSpreadsheet\Cell\Coordinate;
 use PhpOffice\PhpSpreadsheet\Exception as PhpSpreadsheetException;
+use PhpOffice\PhpSpreadsheet\Shared\StringHelper;
 use PhpOffice\PhpSpreadsheet\Worksheet\Table\TableStyle;
 
 class Table
@@ -226,10 +227,11 @@ class Table
     {
         if ($this->name !== '' && $worksheet !== null) {
             $spreadsheet = $worksheet->getParent();
+            $tableName = StringHelper::strToUpper($this->name);
 
             foreach ($spreadsheet->getWorksheetIterator() as $sheet) {
                 foreach ($sheet->getTableCollection() as $table) {
-                    if ($table->getName() === $this->name) {
+                    if (StringHelper::strToUpper($table->getName()) === $tableName) {
                         throw new PhpSpreadsheetException("Workbook already contains a table named '{$this->name}'");
                     }
                 }

src/PhpSpreadsheet/Worksheet/Worksheet.php

@@ -2158,8 +2158,9 @@ class Worksheet implements IComparable
      */
     public function removeTableByName(string $name): self
     {
+        $name = Shared\StringHelper::strToUpper($name);
         foreach ($this->tableCollection as $key => $table) {
-            if ($table->getName() === $name) {
+            if (Shared\StringHelper::strToUpper($table->getName()) === $name) {
                 unset($this->tableCollection[$key]);
             }
         }

tests/PhpSpreadsheetTests/Worksheet/Table/RemoveTableTest.php

@@ -18,7 +18,7 @@ class RemoveTableTest extends SetupTeardown
 
         self::assertEquals(1, $sheet->getTableCollection()->count());
 
-        $sheet->removeTableByName('Table1');
+        $sheet->removeTableByName('table1'); // case insensitive
         self::assertEquals(0, $sheet->getTableCollection()->count());
     }
 

tests/PhpSpreadsheetTests/Worksheet/Table/TableTest.php

@@ -87,7 +87,7 @@ class TableTest extends SetupTeardown
         $sheet->addTable($table1);
 
         $table2 = new Table();
-        $table2->setName('Table_1');
+        $table2->setName('table_1'); // case insensitive
         $sheet->addTable($table2);
     }