Add infrastructure for storing a VARIADIC ANY function's VARIADIC flag.

Originally we didn't bother to mark FuncExprs with any indication whether
VARIADIC had been given in the source text, because there didn't seem to be
any need for it at runtime.  However, because we cannot fold a VARIADIC ANY
function's arguments into an array (since they're not necessarily all the
same type), we do actually need that information at runtime if VARIADIC ANY
functions are to respond unsurprisingly to use of the VARIADIC keyword.
Add the missing field, and also fix ruleutils.c so that VARIADIC ANY
function calls are dumped properly.

Extracted from a larger patch that also fixes concat() and format() (the
only two extant VARIADIC ANY functions) to behave properly when VARIADIC is
specified.  This portion seems appropriate to review and commit separately.

Pavel Stehule

1 files changed, 18 insertions, 4 deletions

diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index 55c4a136441..657a18b1be4 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -110,7 +110,7 @@ static Node *simplify_boolean_equality(Oid opno, List *args);
 static Expr *simplify_function(Oid funcid,
 				  Oid result_type, int32 result_typmod,
 				  Oid result_collid, Oid input_collid, List **args_p,
-				  bool process_args, bool allow_non_const,
+				  bool funcvariadic, bool process_args, bool allow_non_const,
 				  eval_const_expressions_context *context);
 static List *expand_function_arguments(List *args, Oid result_type,
 						  HeapTuple func_tuple);
@@ -121,10 +121,12 @@ static void recheck_cast_function_args(List *args, Oid result_type,
 						   HeapTuple func_tuple);
 static Expr *evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
 				  Oid result_collid, Oid input_collid, List *args,
+				  bool funcvariadic,
 				  HeapTuple func_tuple,
 				  eval_const_expressions_context *context);
 static Expr *inline_function(Oid funcid, Oid result_type, Oid result_collid,
 				Oid input_collid, List *args,
+				bool funcvariadic,
 				HeapTuple func_tuple,
 				eval_const_expressions_context *context);
 static Node *substitute_actual_parameters(Node *expr, int nargs, List *args,
@@ -2314,6 +2316,7 @@ eval_const_expressions_mutator(Node *node,
 										   expr->funccollid,
 										   expr->inputcollid,
 										   &args,
+										   expr->funcvariadic,
 										   true,
 										   true,
 										   context);
@@ -2330,6 +2333,7 @@ eval_const_expressions_mutator(Node *node,
 				newexpr->funcid = expr->funcid;
 				newexpr->funcresulttype = expr->funcresulttype;
 				newexpr->funcretset = expr->funcretset;
+				newexpr->funcvariadic = expr->funcvariadic;
 				newexpr->funcformat = expr->funcformat;
 				newexpr->funccollid = expr->funccollid;
 				newexpr->inputcollid = expr->inputcollid;
@@ -2359,6 +2363,7 @@ eval_const_expressions_mutator(Node *node,
 										   expr->opcollid,
 										   expr->inputcollid,
 										   &args,
+										   false,
 										   true,
 										   true,
 										   context);
@@ -2464,6 +2469,7 @@ eval_const_expressions_mutator(Node *node,
 											   &args,
 											   false,
 											   false,
+											   false,
 											   context);
 					if (simple) /* successfully simplified it */
 					{
@@ -2665,6 +2671,7 @@ eval_const_expressions_mutator(Node *node,
 										   InvalidOid,
 										   InvalidOid,
 										   &args,
+										   false,
 										   true,
 										   true,
 										   context);
@@ -2697,6 +2704,7 @@ eval_const_expressions_mutator(Node *node,
 											   InvalidOid,
 											   &args,
 											   false,
+											   false,
 											   true,
 											   context);
 					if (simple) /* successfully simplified input fn */
@@ -3565,7 +3573,7 @@ simplify_boolean_equality(Oid opno, List *args)
 static Expr *
 simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
 				  Oid result_collid, Oid input_collid, List **args_p,
-				  bool process_args, bool allow_non_const,
+				  bool funcvariadic, bool process_args, bool allow_non_const,
 				  eval_const_expressions_context *context)
 {
 	List	   *args = *args_p;
@@ -3609,7 +3617,8 @@ simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
 	/* Now attempt simplification of the function call proper. */
 
 	newexpr = evaluate_function(funcid, result_type, result_typmod,
-								result_collid, input_collid, args,
+								result_collid, input_collid,
+								args, funcvariadic,
 								func_tuple, context);
 
 	if (!newexpr && allow_non_const && OidIsValid(func_form->protransform))
@@ -3625,6 +3634,7 @@ simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
 		fexpr.funcid = funcid;
 		fexpr.funcresulttype = result_type;
 		fexpr.funcretset = func_form->proretset;
+		fexpr.funcvariadic = funcvariadic;
 		fexpr.funcformat = COERCE_EXPLICIT_CALL;
 		fexpr.funccollid = result_collid;
 		fexpr.inputcollid = input_collid;
@@ -3638,7 +3648,7 @@ simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
 
 	if (!newexpr && allow_non_const)
 		newexpr = inline_function(funcid, result_type, result_collid,
-								  input_collid, args,
+								  input_collid, args, funcvariadic,
 								  func_tuple, context);
 
 	ReleaseSysCache(func_tuple);
@@ -3878,6 +3888,7 @@ recheck_cast_function_args(List *args, Oid result_type, HeapTuple func_tuple)
 static Expr *
 evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
 				  Oid result_collid, Oid input_collid, List *args,
+				  bool funcvariadic,
 				  HeapTuple func_tuple,
 				  eval_const_expressions_context *context)
 {
@@ -3959,6 +3970,7 @@ evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
 	newexpr->funcid = funcid;
 	newexpr->funcresulttype = result_type;
 	newexpr->funcretset = false;
+	newexpr->funcvariadic = funcvariadic;
 	newexpr->funcformat = COERCE_EXPLICIT_CALL;	/* doesn't matter */
 	newexpr->funccollid = result_collid;		/* doesn't matter */
 	newexpr->inputcollid = input_collid;
@@ -4001,6 +4013,7 @@ evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
 static Expr *
 inline_function(Oid funcid, Oid result_type, Oid result_collid,
 				Oid input_collid, List *args,
+				bool funcvariadic,
 				HeapTuple func_tuple,
 				eval_const_expressions_context *context)
 {
@@ -4089,6 +4102,7 @@ inline_function(Oid funcid, Oid result_type, Oid result_collid,
 	fexpr->funcid = funcid;
 	fexpr->funcresulttype = result_type;
 	fexpr->funcretset = false;
+	fexpr->funcvariadic = funcvariadic;
 	fexpr->funcformat = COERCE_EXPLICIT_CALL;	/* doesn't matter */
 	fexpr->funccollid = result_collid;	/* doesn't matter */
 	fexpr->inputcollid = input_collid;