Only report exact case matches.

Be sneaky and work even on case-insensitive file systems.

Author: coke

xt/rakudoc-types.rakutest

@@ -40,6 +40,23 @@ sub render-node($node) {
     $result;
 }
 
+# given a slashy type, see if that file exists on disk
+# To work on case-insensitive file systems, we grep the dir listing
+# rather than check a preconstructed path.
+
+sub file-exists($type) {
+    my @parts = $type.split('/');
+
+    my $path = "doc/Type".IO;
+    while @parts {
+       my $part = @parts.shift;
+       $part ~= '.rakudoc' unless @parts.elems;
+       return False unless $path.dir.grep(*.basename eq $part);
+       $path = $path.child($part);
+    }
+    return True;
+}
+
 sub is-valid-type($node, $parent, $file) {
     # only care about I<>, C<>, L<>, etc.
     return unless $node ~~ Pod::FormattingCode;
@@ -49,7 +66,8 @@ sub is-valid-type($node, $parent, $file) {
     my $type = $node.contents.join('');
     my $type-slash = $type.subst('::', '/', :g);
     my $type-colon = $type.subst('/', '::', :g);
-    return unless "doc/Type/$type-slash.rakudoc".IO.f;
+
+    return unless file-exists($type-slash);
 
     if $file eq "doc/Type/$type-slash.rakudoc" {
         # We are on the same page as this type. Don't link it, only C<> it.