Add status_message_with_fallback GH#105,#114

Changes

@@ -2,6 +2,7 @@ Revision history for HTTP-Message
 
 {{$NEXT}}
     - Add support for RFC 8187 encoded filenames (GH#115) (Zaki Mughal)
+    - Add status_message_with_fallback function that returns default status messages for unknown status codes. (GH#105,#114) (Robert Rothenberg)
 
 6.18      2018-06-05 16:29:15Z
     - Revert status_message to original code (GH#111) (Theo van Hoesel)

lib/HTTP/Status.pm

@@ -9,7 +9,7 @@ require 5.002;   # because we use prototypes
 
 use base 'Exporter';
 our @EXPORT = qw(is_info is_success is_redirect is_error status_message);
-our @EXPORT_OK = qw(is_client_error is_server_error is_cacheable_by_default);
+our @EXPORT_OK = qw(is_client_error is_server_error is_cacheable_by_default status_message_with_fallback);
 
 # Note also addition of mnemonics to @EXPORT below
 
@@ -129,6 +129,18 @@ our %EXPORT_TAGS = (
 
 sub status_message  ($) { $StatusCode{$_[0]}; }
 
+sub status_message_with_fallback ($) {
+    status_message( $_[0] )
+      || (
+          is_info( $_[0] )         ? 'OK'
+        : is_success( $_[0] )      ? 'OK'
+        : is_redirect( $_[0] )     ? 'Redirect'
+        : is_client_error( $_[0] ) ? 'Client Error'
+        : is_server_error( $_[0] ) ? 'Server Error'
+        :                            undef
+      );
+}
+
 sub is_info                 ($) { $_[0] && $_[0] >= 100 && $_[0] < 200; }
 sub is_success              ($) { $_[0] && $_[0] >= 200 && $_[0] < 300; }
 sub is_redirect             ($) { $_[0] && $_[0] >= 300 && $_[0] < 400; }
@@ -262,7 +274,18 @@ The status_message() function will translate status codes to human
 readable strings. The string is the same as found in the constant
 names above. If the $code is not registered in the L<list of IANA HTTP Status
 Codes|https://www.iana.org/assignments/http-status-codes/http-status-codes.xhtml>
-then C<undef> is returned. 
+then C<undef> is returned.
+
+=item status_message_with_fallback( $code )
+
+This function will return corresponding status message, if the code is
+defined.  Otherwise it will return a default message based on the
+code range.
+
+Use this function instead of C<status_message> if your code always
+assumes that there is a defined status message.
+
+This function is not exported by default.
 
 =item is_info( $code )
 

t/status-message-with-fallback.t

@@ -0,0 +1,19 @@
+use strict;
+use warnings;
+
+use Test::More;
+plan tests => 12;
+
+use HTTP::Status qw(status_message status_message_with_fallback);
+
+foreach my $code (100, 200, 300, 400, 500) {
+    is(status_message_with_fallback($code), status_message($code));
+}
+
+is(status_message_with_fallback(0), undef);
+is(status_message_with_fallback(199), "OK");
+is(status_message_with_fallback(299), "OK");
+is(status_message_with_fallback(399), "Redirect");
+is(status_message_with_fallback(499), "Client Error");
+is(status_message_with_fallback(599), "Server Error");
+is(status_message_with_fallback(600), undef);