Fix for 3 Issues Involving ReadXlsx and NamedRange (PHPOffice#1742)

* Fix for 3 Issues Involving ReadXlsx and NamedRange

Issues PHPOffice#1686 and PHPOffice#1723, which provide sample spreadsheets, are probably
solved by this ticket. Issue PHPOffice#1730 is also probably solved, but I have
no way to verify.

There are two problems with how PhpSpreadsheet is handling things now.
Although the first problem is much less severe, and isn't really a factor
in the issues named above, it is helpful to get it out of the way first.
If you define a named range in Excel, and then delete the sheet where
the range exists, Excel saves the range as #REF!. If there is a cell which
references the range, it will similarly have the value #REF! when you open
the Excel file.
Currently, PhpSpreadsheet discards the #REF! definition, so a cell which
references the range will appear as #NAME? rather than #REF!.
This PR changes the behavior so that PhpSpreadsheet retains the #REF!
definition, and cells which reference it will appear as #REF!.

The second problem is the more severe, and is, I believe, responsible
for the 3 issues identified above.
If you define a named range and the sheet on which the range is defined
does not exist at the time, Excel will save the range as something like:

'[1]Unknown Sheet'!$A$1

If a cell references such a range, Excel will again display #REF!.
PhpSpreadsheet currently throws an Exception when it encounters
such a definition while reading the file. This PR changes
the behavior so that PhpSpreadsheet saves the definition as #REF!,
and cells which reference it will behave similarly.

For the record, I will note that Excel does not magically recalculate when a
missing sheet is subsequently added, despite the fact that the reference
might now become resolvable. PhpSpreadsheet behaves likewise.

* Remove Dead Code in Test

Identified it after push but before merge.

src/PhpSpreadsheet/Reader/Xlsx.php

@@ -1277,7 +1277,7 @@ public function load($pFilename)
                                     }
 
                                     // Valid range?
-                                    if (stripos((string) $definedName, '#REF!') !== false || $extractedRange == '') {
+                                    if ($extractedRange == '') {
                                         continue;
                                     }
 
@@ -1347,7 +1347,7 @@ public function load($pFilename)
                                 $extractedRange = (string) $definedName;
 
                                 // Valid range?
-                                if (stripos((string) $definedName, '#REF!') !== false || $extractedRange == '') {
+                                if ($extractedRange == '') {
                                     continue;
                                 }
 
@@ -1395,6 +1395,9 @@ public function load($pFilename)
                                         $locatedSheet = $excel->getSheetByName($extractedSheetName);
                                     }
 
+                                    if ($locatedSheet === null && !DefinedName::testIfFormula($definedRange)) {
+                                        $definedRange = '#REF!';
+                                    }
                                     $excel->addDefinedName(DefinedName::createInstance((string) $definedName['name'], $locatedSheet, $definedRange, false));
                                 }
                             }

tests/PhpSpreadsheetTests/Reader/Xlsx/NamedRangeTest.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheetTests\Reader\Xlsx;
+
+use PhpOffice\PhpSpreadsheet\Reader\Xlsx;
+use PHPUnit\Framework\TestCase;
+
+class NamedRangeTest extends TestCase
+{
+    public static function testBug1686b(): void
+    {
+        $xlsxFile = 'tests/data/Reader/XLSX/bug1686b.xlsx';
+        $reader = new Xlsx();
+        $spreadsheet = $reader->load($xlsxFile);
+        $sheet = $spreadsheet->getActiveSheet();
+        self::assertEquals(2.1, $sheet->getCell('A1')->getCalculatedValue());
+        self::assertEquals('#REF!', $sheet->getCell('A2')->getCalculatedValue());
+        self::assertEquals('#REF!', $sheet->getCell('A3')->getCalculatedValue());
+        self::assertEquals('#NAME?', $sheet->getCell('A4')->getCalculatedValue());
+        self::assertEquals('#REF!', $sheet->getCell('A5')->getCalculatedValue());
+    }
+}