Make bad links in Markdown not fail

Links such as []{pokemon:mewthree} can come from users, so they should not
crash the parser.
So, when an object is not found (or more than one is found), call
identifier_url() directly, instead of failing to get the object for
object_url(). Essentially, treat the link as having an unknown category
(like mechanic:, currently).

The test that check the pokédex descriptions updated so that only
links to known objects and "mechanic:" are allowed.

pokedex/db/markdown.py

@@ -170,16 +170,22 @@ class PokedexLinkPattern(markdown.inlinepatterns.Pattern):
                 query = query.join(tables.Pokemon.species)
                 query = query.filter(
                         tables.PokemonSpecies.identifier == pokemon_ident)
-                obj = query.one()
             else:
-                obj = util.get(self.session, table, target)
+                query = session.query(table)
+                query = query.filter(table.identifier == target)
+            try:
+                obj = query.one()
+            except Exception:
+                obj = name = target
+                url = self.factory.identifier_url(category, obj)
+            else:
                 url = self.factory.object_url(category, obj)
                 url = url or self.factory.identifier_url(category, target)
                 name = None
-            # Translations can be incomplete; in which case we want to use a
+                # Translations can be incomplete; in which case we want to use
-            # fallback.
+                # a fallback.
                 if table in [tables.Type] and self.string_language:
-                # Type wants to be localized to the same language as the text
+                    # Type wants to be localized to the text language
                     name = obj.name_map.get(self.string_language)
                 if not name and self.game_language:
                     name = obj.name_map.get(self.game_language)
@@ -222,12 +228,18 @@ class PokedexLinkExtension(markdown.Extension):
 
         Returns None by default, which causes <span> to be used in place of
         <a>.
+
+        This method is also called for non-existent objects, e.g.
+        []{pokemon:bogus}.
         """
         return None
 
     def object_url(self, category, obj):
-        """Return the URL for the ORM object `obj`.
+        u"""Return the URL for the ORM object `obj`.
 
         Returns None by default, which causes identifier_url to be tried.
+
+        Note that obj may be a Pokémon form. Unlike other returned objects,
+        these do not have identifiers. Be sure to test this case.
         """
         return None

pokedex/tests/test_strings.py

@@ -92,9 +92,9 @@ def test_markdown():
 
 def test_markdown_string():
     en = util.get(connection, tables.Language, 'en')
-    md = markdown.MarkdownString('[]{move:thunderbolt} [paralyzes]{mechanic:paralysis} []{form:sky shaymin}', connection, en)
+    md = markdown.MarkdownString('[]{move:thunderbolt} [paralyzes]{mechanic:paralysis} []{form:sky shaymin}. []{pokemon:mewthree} does not exist.', connection, en)
-    assert unicode(md) == 'Thunderbolt paralyzes Sky Shaymin'
+    assert unicode(md) == 'Thunderbolt paralyzes Sky Shaymin. mewthree does not exist.'
-    assert md.as_html() == '<p><span>Thunderbolt</span> <span>paralyzes</span> <span>Sky Shaymin</span></p>'
+    assert md.as_html() == '<p><span>Thunderbolt</span> <span>paralyzes</span> <span>Sky Shaymin</span>. <span>mewthree</span> does not exist.</p>'
 
     class ObjectTestExtension(markdown.PokedexLinkExtension):
         def object_url(self, category, obj):
@@ -109,9 +109,9 @@ def test_markdown_string():
             return "%s/%s" % (category, ident)
 
     assert md.as_html(extension_cls=ObjectTestExtension) == (
-            '<p><a href="move/thunderbolt">Thunderbolt</a> <span>paralyzes</span> <a href="form/sky shaymin">Sky Shaymin</a></p>')
+            '<p><a href="move/thunderbolt">Thunderbolt</a> <span>paralyzes</span> <a href="form/sky shaymin">Sky Shaymin</a>. <span>mewthree</span> does not exist.</p>')
     assert md.as_html(extension_cls=IdentifierTestExtension) == (
-            '<p><a href="move/thunderbolt">Thunderbolt</a> <a href="mechanic/paralysis">paralyzes</a> <a href="form/sky shaymin">Sky Shaymin</a></p>')
+            '<p><a href="move/thunderbolt">Thunderbolt</a> <a href="mechanic/paralysis">paralyzes</a> <a href="form/sky shaymin">Sky Shaymin</a>. <a href="pokemon/mewthree">mewthree</a> does not exist.</p>')
 
 def markdown_column_params():
     """Check all markdown values
@@ -136,23 +136,28 @@ def test_markdown_values(parent_class, translation_class, column_name):
     query = connection.query(parent_class)
     if translation_class:
         query = query.join(translation_class)
-    for item in query:
-        for language, markdown in getattr(item, column_name + '_map').items():
 
-            if markdown is None:
+    for item in query:
+        for language, md_text in getattr(item, column_name + '_map').items():
+
+            if md_text is None:
                 continue
 
             key = u"Markdown in {0} #{1}'s {2} (lang={3})".format(
                     parent_class.__name__, item.id, column_name, language.identifier)
 
-            try:
+            class TestExtension(markdown.PokedexLinkExtension):
-                text = markdown.as_text()
+                def object_url(self, category, obj):
-            except NoResultFound:
+                    "Swallow good links"
-                assert False, u"{0} references something that doesn't exist:\n{1}".format(
+                    return 'ok'
-                        key, markdown.source_text)
+
-            except AttributeError:
+                def identifier_url(self, category, ident):
-                print markdown
+                    "Only allow mechanic links here (good links handled in object_url)"
-                raise
+                    assert category == 'mechanic', (
+                            '%s: unknown link target: {%s:%s}' %
+                            (key, category, ident))
+
+            text = md_text.as_html(extension_cls=TestExtension)
 
             error_message = u"{0} leaves syntax cruft:\n{1}"
             error_message = error_message.format(key, text)