config: support tests_extras

Some test suites install files that can't be auto-detected, so support a
tests-extras file to add extra files to the -tests package (not
-extras-tests).

Author: rossburton

README.rst

@@ -391,6 +391,12 @@ dev_extras
   functionality to place files used only for development against this
   software that Autospec does not automatically detect.
 
+tests_extras
+  Same as "extras" above, but instead of the files being placed in an
+  ``-extras`` subpackage, they will be placed in the ``-tests`` one. Use this
+  functionality to place files used only for testing against this
+  software that Autospec does not automatically detect.
+
 ${custom}_extras
   Same as "extras" above, but instead of the files being placed in an
   ``-extras`` subpackage, they will be placed in the ``extras-${custom}``

autospec/config.py

@@ -756,7 +756,7 @@ def parse_config_files(self, path, bump, filemanager, version, requirements):
             if re.search(r'.+_extras$', fname):
                 # Prefix all but blessed names with extras-
                 name = fname[:-len("_extras")]
-                if name not in ('dev'):
+                if name not in ('dev', 'tests'):
                     name = f'extras-{name}'
             elif fname == 'extras':
                 name = 'extras'