Increase coverage

tests/test_flattend_spider.py

@@ -72,3 +72,6 @@ def test_extension_error():
         'file_name': 'file',
         'url': 'http://example.com/example/file'
     }
+
+    with pytest.raises(StopIteration):
+        next(generator)

tests/test_util.py

@@ -1,6 +1,6 @@
 import pytest
 
-from kingfisher_scrapy.util import get_parameter_value, replace_parameters
+from kingfisher_scrapy.util import components, get_parameter_value, replace_parameters
 
 
 @pytest.mark.parametrize('url,value,expected', [
@@ -20,3 +20,12 @@ def test_replace_parameters(url, value, expected):
 ])
 def test_get_parameter_value(url, expected):
     assert get_parameter_value(url, 'page') == expected
+
+
+@pytest.mark.parametrize('url,expected', [
+    ('http://example.com/example/file.json', 'file'),
+    ('http://example.com/example/file.xlsx', 'file'),
+    ('http://example.com/example/file.csv', 'file'),
+])
+def test_components(url, expected):
+    assert components(-1)(url) == expected