Fixed #22738 -- Abstracted boolean field type introspection

Thanks maxi for the report, Shai Berger for his help with the patch
and Tim Graham for the review.

3 files changed, 17 insertions, 17 deletions

diff --git a/django/db/backends/__init__.py b/django/db/backends/__init__.py
index 9873d9cba6..8bdf6eed3c 100644
--- a/django/db/backends/__init__.py
+++ b/django/db/backends/__init__.py
@@ -614,8 +614,8 @@ class BaseDatabaseFeatures(object):
     # Can the backend introspect an BinaryField, instead of an TextField?
     can_introspect_binary_field = True
 
-    # Can the backend introspect an BooleanField, instead of an IntegerField?
-    can_introspect_boolean_field = True
+    # What is the type returned when the backend introspect a BooleanField?
+    introspected_boolean_field_type = 'BooleanField'
 
     # Can the backend introspect an DecimalField, instead of an FloatField?
     can_introspect_decimal_field = True
diff --git a/django/db/backends/mysql/base.py b/django/db/backends/mysql/base.py
index 7223780081..0bd9c16e56 100644
--- a/django/db/backends/mysql/base.py
+++ b/django/db/backends/mysql/base.py
@@ -178,7 +178,7 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     supports_regex_backreferencing = False
     supports_date_lookup_using_string = False
     can_introspect_binary_field = False
-    can_introspect_boolean_field = False
+    introspected_boolean_field_type = 'IntegerField'
     can_introspect_small_integer_field = True
     supports_timezones = False
     requires_explicit_null_ordering_when_grouping = True
diff --git a/django/db/backends/oracle/base.py b/django/db/backends/oracle/base.py
index 083ba18daa..c9a59d3970 100644
--- a/django/db/backends/oracle/base.py
+++ b/django/db/backends/oracle/base.py
@@ -125,6 +125,20 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     # select for update with limit can be achieved on Oracle, but not with the current backend.
     supports_select_for_update_with_limit = False
 
+    @cached_property
+    def introspected_boolean_field_type(self):
+        """
+        Some versions of Oracle -- we've seen this on 11.2.0.1 and suspect
+        it goes back -- have a weird bug where, when an integer column is
+        defined with a default, its precision is later reported on introspection
+        as 0, regardless of the real precision. For Django introspection, this
+        means that such columns are reported as IntegerField even if they are
+        really BigIntegerField or BooleanField.
+
+        The bug is solved in Oracle 11.2.0.2 and up.
+        """
+        return 'IntegerField' if self.connection.oracle_full_version < '11.2.0.2' else 'BooleanField'
+
 
 class DatabaseOperations(BaseDatabaseOperations):
     compiler_module = "django.db.backends.oracle.compiler"
@@ -735,20 +749,6 @@ class DatabaseWrapper(BaseDatabaseWrapper):
         except ValueError:
             return None
 
-    @cached_property
-    def version_has_default_introspection_bug(self):
-        """
-        Some versions of Oracle -- we've seen this on 11.2.0.1 and suspect
-        it goes back -- have a weird bug where, when an integer column is
-        defined with a default, its precision is later reported on introspection
-        as 0, regardless of the real precision. For Django introspection, this
-        means that such columns are reported as IntegerField even if they are
-        really BigIntegerField or BooleanField.
-
-        The bug is solved in Oracle 11.2.0.2 and up.
-        """
-        return self.oracle_full_version < '11.2.0.2'
-
 
 class OracleParam(object):
     """