Fix plpython so that it again honors typmod while assigning to tuple fields.

This was broken in 9.0 while improving plpython's conversion behavior for
bytea and boolean.  Per bug report from maizi.

src/pl/plpython/expected/plpython_trigger.out

@@ -523,3 +523,29 @@ SELECT * FROM trigger_test;
  0 | 
 (1 row)
 
+--
+-- Test that triggers honor typmod when assigning to tuple fields,
+-- as per an early 9.0 bug report
+--
+SET DateStyle = 'ISO';
+CREATE FUNCTION set_modif_time() RETURNS trigger AS $$
+    TD['new']['modif_time'] = '2010-10-13 21:57:28.930486'
+    return 'MODIFY'
+$$ LANGUAGE plpythonu;
+CREATE TABLE pb (a TEXT, modif_time TIMESTAMP(0) WITHOUT TIME ZONE);
+CREATE TRIGGER set_modif_time BEFORE UPDATE ON pb
+  FOR EACH ROW EXECUTE PROCEDURE set_modif_time();
+INSERT INTO pb VALUES ('a', '2010-10-09 21:57:33.930486');
+SELECT * FROM pb;
+ a |     modif_time      
+---+---------------------
+ a | 2010-10-09 21:57:34
+(1 row)
+
+UPDATE pb SET a = 'b';
+SELECT * FROM pb;
+ a |     modif_time      
+---+---------------------
+ b | 2010-10-13 21:57:29
+(1 row)
+

src/pl/plpython/plpython.c

@@ -153,10 +153,8 @@ typedef union PLyTypeInput
  */
 
 struct PLyObToDatum;
-struct PLyTypeInfo;
-typedef Datum (*PLyObToDatumFunc) (struct PLyTypeInfo *,
-											   struct PLyObToDatum *,
-											   PyObject *);
+typedef Datum (*PLyObToDatumFunc) (struct PLyObToDatum *, int32 typmod,
+								   PyObject *);
 
 typedef struct PLyObToDatum
 {
@@ -346,14 +344,10 @@ static PyObject *PLyList_FromArray(PLyDatumToOb *arg, Datum d);
 
 static PyObject *PLyDict_FromTuple(PLyTypeInfo *, HeapTuple, TupleDesc);
 
-static Datum PLyObject_ToBool(PLyTypeInfo *, PLyObToDatum *,
-				 PyObject *);
-static Datum PLyObject_ToBytea(PLyTypeInfo *, PLyObToDatum *,
-				  PyObject *);
-static Datum PLyObject_ToDatum(PLyTypeInfo *, PLyObToDatum *,
-				  PyObject *);
-static Datum PLySequence_ToArray(PLyTypeInfo *, PLyObToDatum *,
-					PyObject *);
+static Datum PLyObject_ToBool(PLyObToDatum *, int32, PyObject *);
+static Datum PLyObject_ToBytea(PLyObToDatum *, int32, PyObject *);
+static Datum PLyObject_ToDatum(PLyObToDatum *, int32, PyObject *);
+static Datum PLySequence_ToArray(PLyObToDatum *, int32, PyObject *);
 
 static HeapTuple PLyMapping_ToTuple(PLyTypeInfo *, PyObject *);
 static HeapTuple PLySequence_ToTuple(PLyTypeInfo *, PyObject *);
@@ -421,7 +415,8 @@ static void
 plpython_error_callback(void *arg)
 {
 	if (PLy_curr_procedure)
-		errcontext("PL/Python function \"%s\"", PLy_procedure_name(PLy_curr_procedure));
+		errcontext("PL/Python function \"%s\"",
+				   PLy_procedure_name(PLy_curr_procedure));
 }
 
 static void
@@ -743,7 +738,9 @@ PLy_modify_tuple(PLyProcedure *proc, PyObject *pltd, TriggerData *tdata,
 			{
 				PLyObToDatum *att = &proc->result.out.r.atts[atti];
 
-				modvalues[i] = (att->func) (&proc->result, att, plval);
+				modvalues[i] = (att->func) (att,
+											tupdesc->attrs[atti]->atttypmod,
+											plval);
 				modnulls[i] = ' ';
 			}
 			else
@@ -1132,9 +1129,7 @@ PLy_function_handler(FunctionCallInfo fcinfo, PLyProcedure *proc)
 		else
 		{
 			fcinfo->isnull = false;
-			rv = (proc->result.out.d.func) (&proc->result,
-											&proc->result.out.d,
-											plrv);
+			rv = (proc->result.out.d.func) (&proc->result.out.d, -1, plrv);
 		}
 	}
 	PG_CATCH();
@@ -2099,9 +2094,7 @@ PLyDict_FromTuple(PLyTypeInfo *info, HeapTuple tuple, TupleDesc desc)
  * type can parse.
  */
 static Datum
-PLyObject_ToBool(PLyTypeInfo *info,
-				 PLyObToDatum *arg,
-				 PyObject *plrv)
+PLyObject_ToBool(PLyObToDatum *arg, int32 typmod, PyObject *plrv)
 {
 	Datum		rv;
 
@@ -2120,9 +2113,7 @@ PLyObject_ToBool(PLyTypeInfo *info,
  * with embedded nulls.  And it's faster this way.
  */
 static Datum
-PLyObject_ToBytea(PLyTypeInfo *info,
-				  PLyObToDatum *arg,
-				  PyObject *plrv)
+PLyObject_ToBytea(PLyObToDatum *arg, int32 typmod, PyObject *plrv)
 {
 	PyObject   *volatile plrv_so = NULL;
 	Datum		rv;
@@ -2164,9 +2155,7 @@ PLyObject_ToBytea(PLyTypeInfo *info,
  * cstring into PostgreSQL type.
  */
 static Datum
-PLyObject_ToDatum(PLyTypeInfo *info,
-				  PLyObToDatum *arg,
-				  PyObject *plrv)
+PLyObject_ToDatum(PLyObToDatum *arg, int32 typmod, PyObject *plrv)
 {
 	PyObject   *volatile plrv_bo = NULL;
 	Datum		rv;
@@ -2202,7 +2191,10 @@ PLyObject_ToDatum(PLyTypeInfo *info,
 		else if (slen > plen)
 			elog(ERROR, "could not convert Python object into cstring: Python string longer than reported length");
 		pg_verifymbstr(plrv_sc, slen, false);
-		rv = InputFunctionCall(&arg->typfunc, plrv_sc, arg->typioparam, -1);
+		rv = InputFunctionCall(&arg->typfunc,
+							   plrv_sc,
+							   arg->typioparam,
+							   typmod);
 	}
 	PG_CATCH();
 	{
@@ -2217,9 +2209,7 @@ PLyObject_ToDatum(PLyTypeInfo *info,
 }
 
 static Datum
-PLySequence_ToArray(PLyTypeInfo *info,
-					PLyObToDatum *arg,
-					PyObject *plrv)
+PLySequence_ToArray(PLyObToDatum *arg, int32 typmod, PyObject *plrv)
 {
 	ArrayType  *array;
 	int			i;
@@ -2251,7 +2241,7 @@ PLySequence_ToArray(PLyTypeInfo *info,
 			 * We don't support arrays of row types yet, so the first argument
 			 * can be NULL.
 			 */
-			elems[i] = arg->elm->func(NULL, arg->elm, obj);
+			elems[i] = arg->elm->func(arg->elm, -1, obj);
 		}
 		Py_XDECREF(obj);
 	}
@@ -2300,7 +2290,7 @@ PLyMapping_ToTuple(PLyTypeInfo *info, PyObject *mapping)
 			}
 			else if (value)
 			{
-				values[i] = (att->func) (info, att, value);
+				values[i] = (att->func) (att, -1, value);
 				nulls[i] = false;
 			}
 			else
@@ -2377,7 +2367,7 @@ PLySequence_ToTuple(PLyTypeInfo *info, PyObject *sequence)
 			}
 			else if (value)
 			{
-				values[i] = (att->func) (info, att, value);
+				values[i] = (att->func) (att, -1, value);
 				nulls[i] = false;
 			}
 
@@ -2437,7 +2427,7 @@ PLyObject_ToTuple(PLyTypeInfo *info, PyObject *object)
 			}
 			else if (value)
 			{
-				values[i] = (att->func) (info, att, value);
+				values[i] = (att->func) (att, -1, value);
 				nulls[i] = false;
 			}
 			else
@@ -3019,7 +3009,9 @@ PLy_spi_execute_plan(PyObject *ob, PyObject *list, long limit)
 				PG_TRY();
 				{
 					plan->values[j] =
-						plan->args[j].out.d.func(NULL, &(plan->args[j].out.d), elem);
+						plan->args[j].out.d.func(&(plan->args[j].out.d),
+												 -1,
+												 elem);
 				}
 				PG_CATCH();
 				{

src/pl/plpython/sql/plpython_trigger.sql

@@ -303,3 +303,26 @@ UPDATE trigger_test SET v = 'null' WHERE i = 0;
 DROP TRIGGER test_null_trigger ON trigger_test;
 
 SELECT * FROM trigger_test;
+
+
+--
+-- Test that triggers honor typmod when assigning to tuple fields,
+-- as per an early 9.0 bug report
+--
+
+SET DateStyle = 'ISO';
+
+CREATE FUNCTION set_modif_time() RETURNS trigger AS $$
+    TD['new']['modif_time'] = '2010-10-13 21:57:28.930486'
+    return 'MODIFY'
+$$ LANGUAGE plpythonu;
+
+CREATE TABLE pb (a TEXT, modif_time TIMESTAMP(0) WITHOUT TIME ZONE);
+
+CREATE TRIGGER set_modif_time BEFORE UPDATE ON pb
+  FOR EACH ROW EXECUTE PROCEDURE set_modif_time();
+
+INSERT INTO pb VALUES ('a', '2010-10-09 21:57:33.930486');
+SELECT * FROM pb;
+UPDATE pb SET a = 'b';
+SELECT * FROM pb;