Fixed problem with decimal.Decimal conversions

ChangeLog

@@ -1,3 +1,8 @@
+2010-02-15  Federico Di Gregorio  <fog@initd.org>
+
+	* Added new Decimal adapter that correctly converts NaN and infinity
+	to PostgreSQL NaN numeric values. Also added tests.
+
 2010-02-15  Daniele Varrazzo  <daniele.varrazzo@gmail.com>
 
 	* lib/errorcodes.py: Updated to PostgreSQL 8.4; added lookup() function.

psycopg/adapter_pdecimal.c

@@ -0,0 +1,253 @@
+/* adapter_pdecimal.c - psycopg Decimal type wrapper implementation
+ *
+ * Copyright (C) 2003-2010 Federico Di Gregorio <fog@debian.org>
+ *
+ * This file is part of psycopg.
+ *
+ * psycopg2 is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders give
+ * permission to link this program with the OpenSSL library (or with
+ * modified versions of OpenSSL that use the same license as OpenSSL),
+ * and distribute linked combinations including the two.
+ *
+ * You must obey the GNU Lesser General Public License in all respects for
+ * all of the code used other than OpenSSL.
+ *
+ * psycopg2 is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ */
+
+#define PY_SSIZE_T_CLEAN
+#include <Python.h>
+#include <structmember.h>
+#include <floatobject.h>
+#include <math.h>
+
+#define PSYCOPG_MODULE
+#include "psycopg/config.h"
+#include "psycopg/python.h"
+#include "psycopg/psycopg.h"
+#include "psycopg/adapter_pdecimal.h"
+#include "psycopg/microprotocols_proto.h"
+
+
+/** the Decimal object **/
+
+static PyObject *
+pdecimal_str(pdecimalObject *self)
+{
+    PyObject *res = NULL;
+    PyObject *check = PyObject_CallMethod(self->wrapped, "is_finite", NULL);
+
+    if (check == Py_True)
+        res = PyObject_Str(self->wrapped);
+    else
+        res = PyString_FromString("'NaN'::numeric");
+
+    Py_DECREF(check);
+    return res;
+}
+
+static PyObject *
+pdecimal_getquoted(pdecimalObject *self, PyObject *args)
+{
+    if (!PyArg_ParseTuple(args, "")) return NULL;
+    return pdecimal_str(self);
+}
+
+static PyObject *
+pdecimal_conform(pdecimalObject *self, PyObject *args)
+{
+    PyObject *res, *proto;
+
+    if (!PyArg_ParseTuple(args, "O", &proto)) return NULL;
+
+    if (proto == (PyObject*)&isqlquoteType)
+        res = (PyObject*)self;
+    else
+        res = Py_None;
+
+    Py_INCREF(res);
+    return res;
+}
+
+/** the Decimal object */
+
+/* object member list */
+
+static struct PyMemberDef pdecimalObject_members[] = {
+    {"adapted", T_OBJECT, offsetof(pdecimalObject, wrapped), RO},
+    {NULL}
+};
+
+/* object method table */
+
+static PyMethodDef pdecimalObject_methods[] = {
+    {"getquoted", (PyCFunction)pdecimal_getquoted, METH_VARARGS,
+     "getquoted() -> wrapped object value as SQL-quoted string"},
+    {"__conform__", (PyCFunction)pdecimal_conform, METH_VARARGS, NULL},
+    {NULL}  /* Sentinel */
+};
+
+/* initialization and finalization methods */
+
+static int
+pdecimal_setup(pdecimalObject *self, PyObject *obj)
+{
+    Dprintf("pdecimal_setup: init pdecimal object at %p, refcnt = "
+        FORMAT_CODE_PY_SSIZE_T,
+        self, ((PyObject *)self)->ob_refcnt
+      );
+
+    Py_INCREF(obj);
+    self->wrapped = obj;
+
+    Dprintf("pdecimal_setup: good pdecimal object at %p, refcnt = "
+        FORMAT_CODE_PY_SSIZE_T,
+        self, ((PyObject *)self)->ob_refcnt
+      );
+    return 0;
+}
+
+static int
+pdecimal_traverse(PyObject *obj, visitproc visit, void *arg)
+{
+    pdecimalObject *self = (pdecimalObject *)obj;
+
+    Py_VISIT(self->wrapped);
+    return 0;
+}
+
+static void
+pdecimal_dealloc(PyObject* obj)
+{
+    pdecimalObject *self = (pdecimalObject *)obj;
+
+    Py_CLEAR(self->wrapped);
+
+    Dprintf("pdecimal_dealloc: deleted pdecimal object at %p, refcnt = "
+        FORMAT_CODE_PY_SSIZE_T,
+        obj, obj->ob_refcnt
+      );
+
+    obj->ob_type->tp_free(obj);
+}
+
+static int
+pdecimal_init(PyObject *obj, PyObject *args, PyObject *kwds)
+{
+    PyObject *o;
+
+    if (!PyArg_ParseTuple(args, "O", &o))
+        return -1;
+
+    return pdecimal_setup((pdecimalObject *)obj, o);
+}
+
+static PyObject *
+pdecimal_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+    return type->tp_alloc(type, 0);
+}
+
+static void
+pdecimal_del(PyObject* self)
+{
+    PyObject_GC_Del(self);
+}
+
+static PyObject *
+pdecimal_repr(pdecimalObject *self)
+{
+    return PyString_FromFormat("<psycopg2._psycopg.Float object at %p>",
+                                self);
+}
+
+
+/* object type */
+
+#define pdecimalType_doc \
+"Decimal(str) -> new Decimal adapter object"
+
+PyTypeObject pdecimalType = {
+    PyObject_HEAD_INIT(NULL)
+    0,
+    "psycopg2._psycopg.Decimal",
+    sizeof(pdecimalObject),
+    0,
+    pdecimal_dealloc, /*tp_dealloc*/
+    0,          /*tp_print*/
+
+    0,          /*tp_getattr*/
+    0,          /*tp_setattr*/
+
+    0,          /*tp_compare*/
+
+    (reprfunc)pdecimal_repr, /*tp_repr*/
+    0,          /*tp_as_number*/
+    0,          /*tp_as_sequence*/
+    0,          /*tp_as_mapping*/
+    0,          /*tp_hash */
+
+    0,          /*tp_call*/
+    (reprfunc)pdecimal_str, /*tp_str*/
+
+    0,          /*tp_getattro*/
+    0,          /*tp_setattro*/
+    0,          /*tp_as_buffer*/
+
+    Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+    pdecimalType_doc, /*tp_doc*/
+
+    pdecimal_traverse, /*tp_traverse*/
+    0,          /*tp_clear*/
+
+    0,          /*tp_richcompare*/
+    0,          /*tp_weaklistoffset*/
+
+    0,          /*tp_iter*/
+    0,          /*tp_iternext*/
+
+    /* Attribute descriptor and subclassing stuff */
+
+    pdecimalObject_methods, /*tp_methods*/
+    pdecimalObject_members, /*tp_members*/
+    0,          /*tp_getset*/
+    0,          /*tp_base*/
+    0,          /*tp_dict*/
+
+    0,          /*tp_descr_get*/
+    0,          /*tp_descr_set*/
+    0,          /*tp_dictoffset*/
+
+    pdecimal_init, /*tp_init*/
+    0, /*tp_alloc  will be set to PyType_GenericAlloc in module init*/
+    pdecimal_new, /*tp_new*/
+    (freefunc)pdecimal_del, /*tp_free  Low-level free-memory routine */
+    0,          /*tp_is_gc For PyObject_IS_GC */
+    0,          /*tp_bases*/
+    0,          /*tp_mro method resolution order */
+    0,          /*tp_cache*/
+    0,          /*tp_subclasses*/
+    0           /*tp_weaklist*/
+};
+
+
+/** module-level functions **/
+
+PyObject *
+psyco_Decimal(PyObject *module, PyObject *args)
+{
+    PyObject *obj;
+
+    if (!PyArg_ParseTuple(args, "O", &obj))
+        return NULL;
+
+    return PyObject_CallFunction((PyObject *)&pdecimalType, "O", obj);
+}

psycopg/adapter_pdecimal.h

@@ -0,0 +1,58 @@
+/* adapter_pdecimal.h - definition for the psycopg Decimal type wrapper
+ *
+ * Copyright (C) 2003-2010 Federico Di Gregorio <fog@debian.org>
+ *
+ * This file is part of psycopg.
+ *
+ * psycopg2 is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders give
+ * permission to link this program with the OpenSSL library (or with
+ * modified versions of OpenSSL that use the same license as OpenSSL),
+ * and distribute linked combinations including the two.
+ *
+ * You must obey the GNU Lesser General Public License in all respects for
+ * all of the code used other than OpenSSL.
+ *
+ * psycopg2 is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ */
+
+#ifndef PSYCOPG_PDECIMAL_H
+#define PSYCOPG_PDECIMAL_H 1
+
+#define PY_SSIZE_T_CLEAN
+#include <Python.h>
+
+#include "psycopg/config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern HIDDEN PyTypeObject pdecimalType;
+
+typedef struct {
+    PyObject_HEAD
+
+    /* this is the real object we wrap */
+    PyObject *wrapped;
+
+} pdecimalObject;
+
+/* functions exported to psycopgmodule.c */
+
+HIDDEN PyObject *psyco_Decimal(PyObject *module, PyObject *args);
+#define psyco_Decimal_doc \
+    "Decimal(obj) -> new decimal.Decimal value"
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* !defined(PSYCOPG_PDECIMAL_H) */

psycopg/psycopgmodule.c

@@ -41,6 +41,7 @@
 #include "psycopg/adapter_binary.h"
 #include "psycopg/adapter_pboolean.h"
 #include "psycopg/adapter_pfloat.h"
+#include "psycopg/adapter_pdecimal.h"
 #include "psycopg/adapter_asis.h"
 #include "psycopg/adapter_list.h"
 #include "psycopg/typecast_binary.h"
@@ -276,6 +277,7 @@ static void
 psyco_adapters_init(PyObject *mod)
 {
     PyObject *call;
+    PyTypeObject *type;
 
     microprotocols_add(&PyFloat_Type, NULL, (PyObject*)&pfloatType);
     microprotocols_add(&PyInt_Type, NULL, (PyObject*)&asisType);
@@ -286,8 +288,9 @@ psyco_adapters_init(PyObject *mod)
     microprotocols_add(&PyUnicode_Type, NULL, (PyObject*)&qstringType);
     microprotocols_add(&PyBuffer_Type, NULL, (PyObject*)&binaryType);
     microprotocols_add(&PyList_Type, NULL, (PyObject*)&listType);
-    microprotocols_add((PyTypeObject*)psyco_GetDecimalType(),
+
-                       NULL, (PyObject*)&asisType);
+    if ((type = (PyTypeObject*)psyco_GetDecimalType()) != NULL)
+        microprotocols_add(type, NULL, (PyObject*)&pdecimalType);
 
     /* the module has already been initialized, so we can obtain the callable
        objects directly from its dictionary :) */
@@ -584,8 +587,8 @@ psyco_is_main_interp(void)
 PyObject *
 psyco_GetDecimalType(void)
 {
-    PyObject *decimalType = NULL;
     static PyObject *cachedType = NULL;
+    PyObject *decimalType = NULL;
     PyObject *decimal;
 
     /* Use the cached object if running from the main interpreter. */
@@ -603,8 +606,7 @@ psyco_GetDecimalType(void)
     }
     else {
         PyErr_Clear();
-        decimalType = (PyObject *)&PyFloat_Type;
+        decimalType = NULL;
-        Py_INCREF(decimalType);
     }
 
     /* Store the object from future uses. */
@@ -637,6 +639,8 @@ static PyMethodDef psycopgMethods[] = {
     {"Boolean",  (PyCFunction)psyco_Boolean,
      METH_VARARGS, psyco_Float_doc},
     {"Float",  (PyCFunction)psyco_Float,
+     METH_VARARGS, psyco_Decimal_doc},
+    {"Decimal",  (PyCFunction)psyco_Decimal,
      METH_VARARGS, psyco_Boolean_doc},
     {"Binary",  (PyCFunction)psyco_Binary,
      METH_VARARGS, psyco_Binary_doc},
@@ -702,6 +706,7 @@ init_psycopg(void)
     isqlquoteType.ob_type  = &PyType_Type;
     pbooleanType.ob_type   = &PyType_Type;
     pfloatType.ob_type     = &PyType_Type;
+    pdecimalType.ob_type   = &PyType_Type;
     asisType.ob_type       = &PyType_Type;
     listType.ob_type       = &PyType_Type;
     chunkType.ob_type      = &PyType_Type;
@@ -714,6 +719,7 @@ init_psycopg(void)
     if (PyType_Ready(&isqlquoteType) == -1) return;
     if (PyType_Ready(&pbooleanType) == -1) return;
     if (PyType_Ready(&pfloatType) == -1) return;
+    if (PyType_Ready(&pdecimalType) == -1) return;
     if (PyType_Ready(&asisType) == -1) return;
     if (PyType_Ready(&listType) == -1) return;
     if (PyType_Ready(&chunkType) == -1) return;
@@ -815,6 +821,7 @@ init_psycopg(void)
     isqlquoteType.tp_alloc = PyType_GenericAlloc;
     pbooleanType.tp_alloc = PyType_GenericAlloc;
     pfloatType.tp_alloc = PyType_GenericAlloc;
+    pdecimalType.tp_alloc = PyType_GenericAlloc;
     connectionType.tp_alloc = PyType_GenericAlloc;
     asisType.tp_alloc = PyType_GenericAlloc;
     qstringType.tp_alloc = PyType_GenericAlloc;

psycopg/typecast_basic.c

@@ -132,8 +132,14 @@ typecast_DECIMAL_cast(const char *s, Py_ssize_t len, PyObject *curs)
         return PyErr_NoMemory();
     strncpy(buffer, s, (size_t) len); buffer[len] = '\0';
     decimalType = psyco_GetDecimalType();
+    /* Fall back on float if decimal is not available */
+    if (decimalType != NULL) {
         res = PyObject_CallFunction(decimalType, "s", buffer);
         Py_DECREF(decimalType);
+    }
+    else {
+        res = PyObject_CallFunction((PyObject*)&PyFloat_Type, "s", buffer);
+    }
     PyMem_Free(buffer);
 
     return res;

psycopg2.cproj

@@ -148,6 +148,7 @@
     <None Include="psycopg2da\PUBLICATION.cfg" />
     <None Include="psycopg2da\README.txt" />
     <None Include="psycopg2da\tests.py" />
+    <None Include="psycopg\adapter_pdecimal.h" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="psycopg\adapter_asis.c" />

psycopg2.sln

@@ -19,11 +19,19 @@ Global
 		Policies = $0
 		$0.TextStylePolicy = $1
 		$1.FileWidth = 120
-		$1.TabWidth = 4
-		$1.TabsToSpaces = True
 		$1.NoTabsAfterNonTabs = False
-		$1.RemoveTrailingWhitespace = True
+		$0.DotNetNamingPolicy = $2
-		$1.EolMarker = Native
+		$2.DirectoryNamespaceAssociation = None
+		$2.ResourceNamePolicy = FileName
+		$0.TextStylePolicy = $3
+		$3.NoTabsAfterNonTabs = False
+		$3.inheritsSet = Mono
+		$3.inheritsScope = text/x-python
+		$3.scope = text/plain
+		$0.StandardHeader = $4
+		$4.Text = 
+		$4.IncludeInNewFiles = False
+		$4.inheritsSet = MITX11License
 		name = psycopg2
 	EndGlobalSection
 EndGlobal

setup.py

@@ -341,7 +341,8 @@ sources = [
     'connection_type.c', 'connection_int.c', 'cursor_type.c', 'cursor_int.c',
     'lobject_type.c', 'lobject_int.c',
     'adapter_qstring.c', 'adapter_pboolean.c', 'adapter_binary.c',
-    'adapter_asis.c', 'adapter_list.c', 'adapter_datetime.c', 'adapter_pfloat.c',
+    'adapter_asis.c', 'adapter_list.c', 'adapter_datetime.c',
+    'adapter_pfloat.c', 'adapter_pdecimal.c',
     'utils.c']
 
 parser = ConfigParser.ConfigParser()

tests/types_basic.py

@@ -59,15 +59,25 @@ class TypesBasicTests(unittest.TestCase):
         self.failUnless(s == 1971, "wrong integer quoting: " + str(s))
         s = self.execute("SELECT %s AS foo", (1971L,))
         self.failUnless(s == 1971L, "wrong integer quoting: " + str(s))
-        # Python 2.4 defaults to Decimal? (Apparently it does not.)
+        if sys.version_info[0] < 2 or sys.version_info[1] < 4:
+            s = self.execute("SELECT %s AS foo", (19.10,))
+            self.failUnless(abs(s - 19.10) < 0.001,
+                        "wrong float quoting: " + str(s))
+
+    def testDecimal(self):
         if sys.version_info[0] >= 2 and sys.version_info[1] >= 4:
             s = self.execute("SELECT %s AS foo", (decimal.Decimal("19.10"),))
             self.failUnless(s - decimal.Decimal("19.10") == 0,
                             "wrong decimal quoting: " + str(s))
-        else:
+            s = self.execute("SELECT %s AS foo", (decimal.Decimal("NaN"),))
-            s = self.execute("SELECT %s AS foo", (19.10,))
+            self.failUnless(str(s) == "NaN", "wrong decimal quoting: " + str(s))
-            self.failUnless(abs(s - 19.10) < 0.001,
+            self.failUnless(type(s) == decimal.Decimal, "wrong decimal conversion: " + repr(s))
-                            "wrong float quoting: " + str(s))
+            s = self.execute("SELECT %s AS foo", (decimal.Decimal("infinity"),))
+            self.failUnless(str(s) == "NaN", "wrong decimal quoting: " + str(s))
+            self.failUnless(type(s) == decimal.Decimal, "wrong decimal conversion: " + repr(s))
+            s = self.execute("SELECT %s AS foo", (decimal.Decimal("-infinity"),))
+            self.failUnless(str(s) == "NaN", "wrong decimal quoting: " + str(s))
+            self.failUnless(type(s) == decimal.Decimal, "wrong decimal conversion: " + repr(s))
 
     def testFloat(self):
         s = self.execute("SELECT %s AS foo", (float("nan"),))