[bug-gettext] xgettext: fatal error after a warning when processing a pot file

[Emil Wojak]

Hi,

This fails:
$ xgettext -o output.pot hello input.pot
xgettext: warning: file `hello' extension `' is unknown; will try C
xgettext: found 1 fatal error
$ ls output.pot
ls: cannot access output.pot: No such file or directory

This succeeds:
$ xgettext -o output.pot input.pot hello
xgettext: warning: file `hello' extension `' is unknown; will try C
$ ls output.pot
output.pot

The outcome depends on the order of files to be processed. Their 
content is irrelevant provided the pot file has correct format. If I 
rename hello to hello.c then both invocations work fine.

I noticed that processing a pot file will fail with the "fatal error" 
message if any of files processed before that issues a warning.

I just debugged vanilla gettext-0.18.3.1 and I found the following. 
When xgettext processes a file without an extension it outputs the 
warning using a function that increments a variable called 
error_message_count.
From src/xgettext.c:
 780           /* Derive the language from the extension, and the 
extractor
 781              function from the language.  */
 782           language = extension_to_language (extension);
 783           if (language == NULL)
 784             {
 785               error (0, 0, _("\
 786 warning: file '%s' extension '%s' is unknown; will try C"), 
filename, extension);
 787               language = "C";
 788             }
 789           this_file_extractor = language_to_extractor (language);
This variable is not checked after processing the file.

On the other hand after processing a pot file there's a check if 
error_message_count > 0 and if so, it exits with the "fatal error" 
message.
From src/read-catalog-abstract.c:
174   /* Parse the stream's content.  */
175   parse_start (pop);
176   input_syntax->parse (pop, fp, real_filename, logical_filename);
177   parse_end (pop);
178
179   if (error_message_count > 0)
180     po_xerror (PO_SEVERITY_FATAL_ERROR, NULL,
181                /*real_filename*/ NULL, (size_t)(-1), (size_t)(-1), 
false,
182                xasprintf (ngettext ("found %d fatal error",
183                                     "found %d fatal errors",
184                                     error_message_count),
185                           error_message_count));
186   error_message_count = 0;
So if the warning is output before processing the pot file, then 
xgettext will exit with fatal error. Otherwise the warning will have no 
further consequences.

I consider this to be a bug in gettext. I would expect xgettext not to 
fail upon a warning.