Add postgresl.REGCLASS type for casting table names to OIDs and vice versa

Fixes: #4160
Change-Id: Id0bdbad1be3a0950dc8f35895ee13d9264244722
Pull-request: https://github.com/zzzeek/sqlalchemy/pull/435

2 files changed, 17 insertions, 3 deletions

diff --git a/lib/sqlalchemy/dialects/postgresql/__init__.py b/lib/sqlalchemy/dialects/postgresql/__init__.py
index a985f06a9..d2f8057b6 100644
--- a/lib/sqlalchemy/dialects/postgresql/__init__.py
+++ b/lib/sqlalchemy/dialects/postgresql/__init__.py
@@ -10,7 +10,7 @@ from . import base, psycopg2, pg8000, pypostgresql, pygresql, \
 
 from .base import \
     INTEGER, BIGINT, SMALLINT, VARCHAR, CHAR, TEXT, NUMERIC, FLOAT, REAL, \
-    INET, CIDR, UUID, BIT, MACADDR, MONEY, OID, DOUBLE_PRECISION, \
+    INET, CIDR, UUID, BIT, MACADDR, MONEY, OID, REGCLASS, DOUBLE_PRECISION, \
     TIMESTAMP, TIME, DATE, BYTEA, BOOLEAN, INTERVAL, ENUM, TSVECTOR, \
     DropEnumType, CreateEnumType
 from .hstore import HSTORE, hstore
@@ -28,8 +28,8 @@ base.dialect = dialect = psycopg2.dialect
 __all__ = (
     'INTEGER', 'BIGINT', 'SMALLINT', 'VARCHAR', 'CHAR', 'TEXT', 'NUMERIC',
     'FLOAT', 'REAL', 'INET', 'CIDR', 'UUID', 'BIT', 'MACADDR', 'MONEY', 'OID',
-    'DOUBLE_PRECISION', 'TIMESTAMP', 'TIME', 'DATE', 'BYTEA', 'BOOLEAN',
-    'INTERVAL', 'ARRAY', 'ENUM', 'dialect', 'array', 'HSTORE',
+    'REGCLASS', 'DOUBLE_PRECISION', 'TIMESTAMP', 'TIME', 'DATE', 'BYTEA',
+    'BOOLEAN', 'INTERVAL', 'ARRAY', 'ENUM', 'dialect', 'array', 'HSTORE',
     'hstore', 'INT4RANGE', 'INT8RANGE', 'NUMRANGE', 'DATERANGE',
     'TSRANGE', 'TSTZRANGE', 'json', 'JSON', 'JSONB', 'Any', 'All',
     'DropEnumType', 'CreateEnumType', 'ExcludeConstraint',
diff --git a/lib/sqlalchemy/dialects/postgresql/base.py b/lib/sqlalchemy/dialects/postgresql/base.py
index 1dffe8db9..c5b0db6ce 100644
--- a/lib/sqlalchemy/dialects/postgresql/base.py
+++ b/lib/sqlalchemy/dialects/postgresql/base.py
@@ -1000,6 +1000,16 @@ class OID(sqltypes.TypeEngine):
     __visit_name__ = "OID"
 
 
+class REGCLASS(sqltypes.TypeEngine):
+
+    """Provide the PostgreSQL REGCLASS type.
+
+    .. versionadded:: 1.2.7
+
+    """
+    __visit_name__ = "REGCLASS"
+
+
 class TIMESTAMP(sqltypes.TIMESTAMP):
 
     def __init__(self, timezone=False, precision=None):
@@ -1382,6 +1392,7 @@ ischema_names = {
     'macaddr': MACADDR,
     'money': MONEY,
     'oid': OID,
+    'regclass': REGCLASS,
     'double precision': DOUBLE_PRECISION,
     'timestamp': TIMESTAMP,
     'timestamp with time zone': TIMESTAMP,
@@ -1876,6 +1887,9 @@ class PGTypeCompiler(compiler.GenericTypeCompiler):
     def visit_OID(self, type_, **kw):
         return "OID"
 
+    def visit_REGCLASS(self, type_, **kw):
+        return "REGCLASS"
+
     def visit_FLOAT(self, type_, **kw):
         if not type_.precision:
             return "FLOAT"