autopkgtest: Handle 'blacklisted' version

The apt version comparison sorts 'blacklisted' greater than most version
numbers, which means that we accidentally apply force hints for version
'blacklisted' to all uploads. Since this is the only case of a hacked
version number, let's special case it so that 'blacklisted' hints only
match packages with 'blacklisted' version.

britney2/policies/autopkgtest.py

@@ -1182,7 +1182,9 @@ class AutopkgtestPolicy(BasePolicy):
             self.logger.info('Checking hints for %s/%s/%s: %s', src, ver, arch, [str(h) for h in hints])
             for hint in hints:
                 if [mi for mi in hint.packages if mi.architecture in ['source', arch] and
-                        (mi.version == 'all' or apt_pkg.version_compare(ver, mi.version) <= 0)]:
+                        (mi.version == 'all' or
+                         (mi.version == 'blacklisted' and ver == 'blacklisted') or
+                         (mi.version != 'blacklisted' and apt_pkg.version_compare(ver, mi.version) <= 0))]:
                     return True
 
         return False

tests/test_autopkgtest.py

@@ -1182,8 +1182,8 @@ class AT(TestAutopkgtestBase):
                                      'brown': ['i386']}})
 
     def test_blacklisted_force(self):
-        '''blacklisted packages return exit code 99 and version all, check they
-        are handled correctly'''
+        '''blacklisted packages return exit code 99 and version blacklisted,
+        check they can be forced over'''
 
         self.data.add_default_packages(black=False)
 
@@ -1205,6 +1205,28 @@ class AT(TestAutopkgtestBase):
 
         self.assertEqual(len(self.amqp_requests), 0)
 
+    def test_blacklisted_force_mismatch(self):
+        '''forcing a blacklisted package doesn't mean you force other versions'''
+
+        self.data.add_default_packages(black=False)
+
+        self.swift.set_results({'autopkgtest-testing': {
+            'testing/amd64/b/black/20150101_100000@': (0, 'black 1', tr('black/1')),
+            'testing/i386/b/black/20150101_100001@': (0, 'black 1', tr('black/1')),
+            'testing/amd64/b/black/20150102_100000@': (4, 'black 2', tr('black/2')),
+            'testing/i386/b/black/20150102_100001@': (4, 'black 2', tr('black/2'))
+        }})
+
+        self.create_hint('autopkgtest', 'force-badtest black/amd64/blacklisted')
+
+        self.run_it(
+            [('black', {'Version': '2'}, 'autopkgtest')],
+            {'black': (False, {'black/2': {'amd64': 'REGRESSION'}})
+            },
+            {'black': [('old-version', '1'), ('new-version', '2')]})
+
+        self.assertEqual(len(self.amqp_requests), 0)
+
     def test_binary_from_new_source_package_pass(self):
         '''building an existing binary for a new source package (pass)'''