Add a convenience routine makeFuncCall to reduce duplication.

David Fetter and Andrew Gierth, reviewed by Jeevan Chalke

src/backend/nodes/makefuncs.c

@@ -508,3 +508,28 @@ makeDefElemExtended(char *nameSpace, char *name, Node *arg,
 
 	return res;
 }
+
+/*
+ * makeFuncCall -
+ *
+ * Initialize a FuncCall struct with the information every caller must
+ * supply.  Any non-default parameters have to be handled by the
+ * caller.
+ *
+ */
+
+FuncCall *
+makeFuncCall(List *name, List *args, int location)
+{
+	FuncCall *n = makeNode(FuncCall);
+	n->funcname = name;
+	n->args = args;
+	n->location = location;
+	n->agg_order = NIL;
+	n->agg_star = FALSE;
+	n->agg_distinct = FALSE;
+	n->func_variadic = FALSE;
+	n->over = NULL;
+	return n;
+}
+

src/backend/parser/parse_utilcmd.c

@@ -448,16 +448,9 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column)
 		castnode->typeName = SystemTypeName("regclass");
 		castnode->arg = (Node *) snamenode;
 		castnode->location = -1;
-		funccallnode = makeNode(FuncCall);
-		funccallnode->funcname = SystemFuncName("nextval");
-		funccallnode->args = list_make1(castnode);
-		funccallnode->agg_order = NIL;
-		funccallnode->agg_star = false;
-		funccallnode->agg_distinct = false;
-		funccallnode->func_variadic = false;
-		funccallnode->over = NULL;
-		funccallnode->location = -1;
-
+		funccallnode = makeFuncCall(SystemFuncName("nextval"),
+									list_make1(castnode),
+									-1);
 		constraint = makeNode(Constraint);
 		constraint->contype = CONSTR_DEFAULT;
 		constraint->location = -1;

src/include/nodes/makefuncs.h

@@ -75,6 +75,8 @@ extern TypeName *makeTypeNameFromOid(Oid typeOid, int32 typmod);
 extern FuncExpr *makeFuncExpr(Oid funcid, Oid rettype, List *args,
 			 Oid funccollid, Oid inputcollid, CoercionForm fformat);
 
+extern FuncCall *makeFuncCall(List *name, List *args, int location);
+
 extern DefElem *makeDefElem(char *name, Node *arg);
 extern DefElem *makeDefElemExtended(char *nameSpace, char *name, Node *arg,
 					DefElemAction defaction);

src/include/nodes/parsenodes.h

@@ -285,6 +285,11 @@ typedef struct CollateClause
  * construct *must* be an aggregate call.  Otherwise, it might be either an
  * aggregate or some other kind of function.  However, if OVER is present
  * it had better be an aggregate or window function.
+ *
+ * Normally, you'd initialize this via makeFuncCall() and then only
+ * change the parts of the struct its defaults don't match afterwards
+ * if needed.
+ *
  */
 typedef struct FuncCall
 {