From 57731a07ef7fdbc99bd7d3a6ff7f06c3cb31e2d7 Mon Sep 17 00:00:00 2001
From: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Date: Thu, 17 Dec 2020 17:29:48 +0100
Subject: [PATCH] Added _oid C attribute to CDumper

---
 psycopg3_c/psycopg3_c/adapt.pyx            | 5 ++++-
 psycopg3_c/psycopg3_c/types/numeric.pyx    | 7 ++++++-
 psycopg3_c/psycopg3_c/types/singletons.pyx | 3 ++-
 psycopg3_c/psycopg3_c/types/text.pyx       | 7 +++----
 4 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/psycopg3_c/psycopg3_c/adapt.pyx b/psycopg3_c/psycopg3_c/adapt.pyx
index 62c928126..c8e3c5cb1 100644
--- a/psycopg3_c/psycopg3_c/adapt.pyx
+++ b/psycopg3_c/psycopg3_c/adapt.pyx
@@ -36,6 +36,7 @@ cdef class CDumper:
     cdef object _context
     cdef object _connection
     cdef PGconn _pgconn
+    cdef impl.Oid _oid
 
     def __init__(self, src: type, context: AdaptContext = None):
         self._src = src
@@ -95,7 +96,9 @@ cdef class CDumper:
 
     @property
     def oid(self) -> int:
-        return 0
+        # Implicitly initialised to zero
+        # Subclasses may implement __cinit__ to set a per-class value
+        return self._oid
 
     @classmethod
     def register(
diff --git a/psycopg3_c/psycopg3_c/types/numeric.pyx b/psycopg3_c/psycopg3_c/types/numeric.pyx
index 4a797d835..aec21dcad 100644
--- a/psycopg3_c/psycopg3_c/types/numeric.pyx
+++ b/psycopg3_c/psycopg3_c/types/numeric.pyx
@@ -21,7 +21,12 @@ cdef extern from "Python.h":
 
 
 cdef class IntDumper(CDumper):
-    oid = oids.INT8_OID
+
+    def __cinit__(self):
+        self._oid = oids.INT8_OID
+
+    def __init__(self, src: type, context: AdaptContext = None):
+        super().__init__(src, context)
 
     def dump(self, obj) -> bytes:
         cdef char buf[22]
diff --git a/psycopg3_c/psycopg3_c/types/singletons.pyx b/psycopg3_c/psycopg3_c/types/singletons.pyx
index 70295d898..8b46f338d 100644
--- a/psycopg3_c/psycopg3_c/types/singletons.pyx
+++ b/psycopg3_c/psycopg3_c/types/singletons.pyx
@@ -9,7 +9,8 @@ from psycopg3_c cimport oids
 
 
 cdef class BoolDumper(CDumper):
-    oid = oids.BOOL_OID
+    def __cinit__(self):
+        self._oid = oids.BOOL_OID
 
     def dump(self, obj) -> bytes:
         # Fast paths, just a pointer comparison
diff --git a/psycopg3_c/psycopg3_c/types/text.pyx b/psycopg3_c/psycopg3_c/types/text.pyx
index cf3b73a81..da80a440d 100644
--- a/psycopg3_c/psycopg3_c/types/text.pyx
+++ b/psycopg3_c/psycopg3_c/types/text.pyx
@@ -98,14 +98,13 @@ cdef class TextLoader(CLoader):
 cdef class BytesDumper(CDumper):
     cdef Escaping esc
 
+    def __cinit__(self):
+        self._oid = oids.BYTEA_OID
+
     def __init__(self, src: type, context: AdaptContext):
         super().__init__(src, context)
         self.esc = Escaping(self._pgconn)
 
-    @property
-    def oid(self) -> int:
-        return oids.BYTEA_OID
-
     def dump(self, obj) -> memoryview:
         return self.esc.escape_bytea(obj)
 
-- 
2.47.2