Introspected alternate SQLite FK definitions

2 files changed, 21 insertions, 2 deletions

diff --git a/django/db/backends/sqlite3/introspection.py b/django/db/backends/sqlite3/introspection.py
index eb80b32c8b..1090aa375b 100644
--- a/django/db/backends/sqlite3/introspection.py
+++ b/django/db/backends/sqlite3/introspection.py
@@ -106,16 +106,23 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
         # Walk through and look for references to other tables. SQLite doesn't
         # really have enforced references, but since it echoes out the SQL used
         # to create the table we can look for REFERENCES statements used there.
+        field_names = []
         for field_index, field_desc in enumerate(results.split(',')):
             field_desc = field_desc.strip()
             if field_desc.startswith("UNIQUE"):
                 continue
 
-            m = re.search('references (.*) \(["|](.*)["|]\)', field_desc, re.I)
+            field_names.append(field_desc.split()[0].strip('"'))
+            m = re.search('references (\S*) ?\(["|]?(.*)["|]?\)', field_desc, re.I)
             if not m:
                 continue
 
             table, column = [s.strip('"') for s in m.groups()]
+            if field_desc.startswith("FOREIGN KEY"):
+                # Find index of the target FK field
+                m = re.match('FOREIGN KEY\(([^\)]*)\).*', field_desc, re.I)
+                fkey_field = m.groups()[0].strip('"')
+                field_index = field_names.index(fkey_field)
 
             cursor.execute("SELECT sql FROM sqlite_master WHERE tbl_name = %s", [table])
             result = cursor.fetchall()[0]
diff --git a/tests/introspection/tests.py b/tests/introspection/tests.py
index 1d39eeacbc..6961bb7c31 100644
--- a/tests/introspection/tests.py
+++ b/tests/introspection/tests.py
@@ -1,8 +1,10 @@
 from __future__ import unicode_literals
 
+from unittest import skipUnless
+
 from django.db import connection
 from django.db.utils import DatabaseError
-from django.test import TransactionTestCase, skipUnlessDBFeature
+from django.test import TransactionTestCase, mock, skipUnlessDBFeature
 
 from .models import Reporter, Article
 
@@ -119,6 +121,16 @@ class IntrospectionTests(TransactionTestCase):
         self.assertEqual(relations, {3: (0, Reporter._meta.db_table),
                                      4: (0, Article._meta.db_table)})
 
+    @skipUnless(connection.vendor == 'sqlite', "This is an sqlite-specific issue")
+    def test_get_relations_alt_format(self):
+        """With SQLite, foreign keys can be added with different syntaxes."""
+        with connection.cursor() as cursor:
+            cursor.fetchone = mock.Mock(return_value=[
+                "CREATE TABLE track(id, art INTEGER, FOREIGN KEY(art) REFERENCES %s(id));" % Article._meta.db_table
+            ])
+            relations = connection.introspection.get_relations(cursor, 'mocked_table')
+        self.assertEqual(relations, {1: (0, Article._meta.db_table)})
+
     @skipUnlessDBFeature('can_introspect_foreign_keys')
     def test_get_key_columns(self):
         with connection.cursor() as cursor: