Callback kwargs: more tests

tests/spiders.py

@@ -39,6 +39,9 @@ class KeywordArgumentsSpider(MockServerSpider):
         yield Request(self.mockserver.url('/general_with'), self.parse_general, cb_kwargs=data)
         yield Request(self.mockserver.url('/general_without'), self.parse_general)
         yield Request(self.mockserver.url('/no_kwargs'), self.parse_no_kwargs)
+        yield Request(self.mockserver.url('/default'), self.parse_default, cb_kwargs=data)
+        yield Request(self.mockserver.url('/takes_less'), self.parse_takes_less, cb_kwargs=data)
+        yield Request(self.mockserver.url('/takes_more'), self.parse_takes_more, cb_kwargs=data)
 
     def parse_first(self, response, key, number):
         self.checks.append(key == 'value')
@@ -66,6 +69,25 @@ class KeywordArgumentsSpider(MockServerSpider):
         self.checks.append(response.url.endswith('/no_kwargs'))
         self.crawler.stats.inc_value('boolean_checks')
 
+    def parse_default(self, response, key, number=None, default=99):
+        self.checks.append(response.url.endswith('/default'))
+        self.checks.append(key == 'value')
+        self.checks.append(number == 123)
+        self.checks.append(default == 99)
+        self.crawler.stats.inc_value('boolean_checks', 4)
+
+    def parse_takes_less(self, response, key):
+        """
+        Should raise
+        TypeError: parse_takes_less() got an unexpected keyword argument 'number'
+        """
+
+    def parse_takes_more(self, response, key, number, other):
+        """
+        Should raise
+        TypeError: parse_takes_more() missing 1 required positional argument: 'other'
+        """
+
 
 class FollowAllSpider(MetaSpider):
 

tests/test_crawl.py

@@ -4,6 +4,7 @@ import logging
 from testfixtures import LogCapture
 from twisted.internet import defer
 from twisted.trial.unittest import TestCase
+import six
 
 from scrapy.http import Request
 from scrapy.crawler import CrawlerRunner
@@ -15,6 +16,8 @@ from tests.mockserver import MockServer
 
 class CrawlTestCase(TestCase):
 
+    maxDiff = None
+
     def setUp(self):
         self.mockserver = MockServer()
         self.mockserver.__enter__()
@@ -26,9 +29,25 @@ class CrawlTestCase(TestCase):
     @defer.inlineCallbacks
     def test_callback_kwargs(self):
         crawler = self.runner.create_crawler(KeywordArgumentsSpider)
-        yield crawler.crawl(mockserver=self.mockserver)
+        with LogCapture() as log:
+            yield crawler.crawl(mockserver=self.mockserver)
         self.assertTrue(all(crawler.spider.checks))
         self.assertEqual(len(crawler.spider.checks), crawler.stats.get_value('boolean_checks'))
+        # check exceptions for argument mismatch
+        exceptions = {}
+        for line in log.records:
+            for key in ('takes_less', 'takes_more'):
+                if key in line.getMessage():
+                    exceptions[key] = line
+        self.assertEqual(exceptions['takes_less'].exc_info[0], TypeError)
+        self.assertEqual(str(exceptions['takes_less'].exc_info[1]), "parse_takes_less() got an unexpected keyword argument 'number'")
+        self.assertEqual(exceptions['takes_more'].exc_info[0], TypeError)
+        # py2 and py3 messages are different
+        exc_message = str(exceptions['takes_more'].exc_info[1])
+        if six.PY2:
+            self.assertEqual(exc_message, "parse_takes_more() takes exactly 5 arguments (4 given)")
+        elif six.PY3:
+            self.assertEqual(exc_message, "parse_takes_more() missing 1 required positional argument: 'other'")
 
     @defer.inlineCallbacks
     def test_follow_all(self):