fix this algorithm again

2 files changed, 33 insertions, 3 deletions

diff --git a/lib/Spreadsheet/ParseXLSX.pm b/lib/Spreadsheet/ParseXLSX.pm
index 8159fa8..209ae6f 100644
--- a/lib/Spreadsheet/ParseXLSX.pm
+++ b/lib/Spreadsheet/ParseXLSX.pm
@@ -575,9 +575,12 @@ sub _cell_to_row_col {
 
     my ($col, $row) = $cell =~ /([A-Z]+)([0-9]+)/;
 
-    (my $ncol = $col) =~ tr/A-Z/1-9A-Q/;
-    $ncol = POSIX::strtol($ncol, 27);
-    $ncol -= 1;
+    my $ncol = 0;
+    for my $char (split //, $col) {
+        $ncol *= 26;
+        $ncol += ord($char) - ord('A') + 1;
+    }
+    $ncol = $ncol - 1;
 
     my $nrow = $row - 1;
 
diff --git a/t/cell-to-row-col.t b/t/cell-to-row-col.t
new file mode 100644
index 0000000..d2ecbaa
--- /dev/null
+++ b/t/cell-to-row-col.t
@@ -0,0 +1,27 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+use Test::More;
+
+use Spreadsheet::ParseXLSX;
+
+my %tests = (
+    A1    => [0,   0],
+    Z3    => [2,   25],
+    AA5   => [4,   26],
+    IV256 => [255, 255],
+    ZZ10  => [9,   701],
+    AAA8  => [7,   702],
+    XFD22 => [21,  16383],
+);
+
+for my $cell (sort keys %tests) {
+    # XXX not public API, but i'm lazy
+    is_deeply(
+        [ Spreadsheet::ParseXLSX->_cell_to_row_col($cell) ],
+        $tests{$cell},
+        "correct value for $cell"
+    );
+}
+
+done_testing;