Defend against possible crash if a plpython function does not specify names

for its arguments.  Also add a regression test, since someone apparently
changed every single plpython test case to use only named parameters; else
we'd have noticed this sooner.

Euler Taveira de Oliveira, per a report from Alvaro

src/pl/plpython/expected/plpython_function.out

@@ -357,8 +357,11 @@ CREATE FUNCTION test_return_none() RETURNS int AS $$
 None
 $$ LANGUAGE plpythonu;
 --
--- Test named parameters
+-- Test named and nameless parameters
 --
+CREATE FUNCTION test_param_names0(integer, integer) RETURNS int AS $$
+return args[0] + args[1]
+$$ LANGUAGE plpythonu;
 CREATE FUNCTION test_param_names1(a0 integer, a1 text) RETURNS boolean AS $$
 assert a0 == args[0]
 assert a1 == args[1]

src/pl/plpython/expected/plpython_test.out

@@ -197,7 +197,13 @@ SELECT test_return_none(), test_return_none() IS NULL AS "is null";
                   | t
 (1 row)
 
--- Test for functions with named parameters
+-- Test for functions with named and nameless parameters
+SELECT test_param_names0(2,7);
+ test_param_names0 
+-------------------
+                 9
+(1 row)
+
 SELECT test_param_names1(1,'text');
  test_param_names1 
 -------------------

src/pl/plpython/plpython.c

 /**********************************************************************
  * plpython.c - python as a procedural language for PostgreSQL
  *
- *	$PostgreSQL: pgsql/src/pl/plpython/plpython.c,v 1.119 2009/03/26 22:26:08 petere Exp $
+ *	$PostgreSQL: pgsql/src/pl/plpython/plpython.c,v 1.120 2009/04/03 16:59:42 tgl Exp $
  *
  *********************************************************************
  */
@@ -1052,9 +1052,11 @@ PLy_function_build_args(FunctionCallInfo fcinfo, PLyProcedure * proc)
 				arg = Py_None;
 			}
 
-			if (PyList_SetItem(args, i, arg) == -1 ||
-				(proc->argnames &&
-				 PyDict_SetItemString(proc->globals, proc->argnames[i], arg) == -1))
+			if (PyList_SetItem(args, i, arg) == -1)
+				PLy_elog(ERROR, "PyList_SetItem() failed for PL/Python function \"%s\" while setting up arguments", proc->proname);
+
+			if (proc->argnames && proc->argnames[i] &&
+				PyDict_SetItemString(proc->globals, proc->argnames[i], arg) == -1)
 				PLy_elog(ERROR, "PyDict_SetItemString() failed for PL/Python function \"%s\" while setting up arguments", proc->proname);
 			arg = NULL;
 		}
@@ -1081,7 +1083,8 @@ PLy_function_delete_args(PLyProcedure * proc)
 		return;
 
 	for (i = 0; i < proc->nargs; i++)
-		PyDict_DelItemString(proc->globals, proc->argnames[i]);
+		if (proc->argnames[i])
+			PyDict_DelItemString(proc->globals, proc->argnames[i]);
 }
 
 

src/pl/plpython/sql/plpython_function.sql

@@ -391,8 +391,12 @@ $$ LANGUAGE plpythonu;
 
 
 --
--- Test named parameters
+-- Test named and nameless parameters
 --
+CREATE FUNCTION test_param_names0(integer, integer) RETURNS int AS $$
+return args[0] + args[1]
+$$ LANGUAGE plpythonu;
+
 CREATE FUNCTION test_param_names1(a0 integer, a1 text) RETURNS boolean AS $$
 assert a0 == args[0]
 assert a1 == args[1]

src/pl/plpython/sql/plpython_test.sql

@@ -74,7 +74,8 @@ SELECT test_void_func1(), test_void_func1() IS NULL AS "is null";
 SELECT test_void_func2(); -- should fail
 SELECT test_return_none(), test_return_none() IS NULL AS "is null";
 
--- Test for functions with named parameters
+-- Test for functions with named and nameless parameters
+SELECT test_param_names0(2,7);
 SELECT test_param_names1(1,'text');
 SELECT test_param_names2(users) from users;
 SELECT test_param_names3(1);