Feature #7566 - Allow DEFAULT keyword in argument list.

doc/sql.extensions/README.named_arguments.md

@@ -30,13 +30,18 @@ named arguments.
     [ {<positional arguments>,} ] <named arguments>
 
 <positional arguments> ::=
-    <value> [ {, <value>}... ]
+    <value or default> [ {, <value or default>}... ]
 
 <named arguments> ::=
     <named argument> [ {, <named argument>}... ]
 
 <named argument> ::=
-    <argument name> => <value>
+    <argument name> => <value or default>
+
+
+<value or default> ::=
+    <value> |
+    DEFAULT
 ```
 
 ## Examples
@@ -51,6 +56,11 @@ select function_name(1, parameter2 => 'Two')
   from rdb$database
 ```
 
+```
+select function_name(default, parameter2 => 'Two')
+  from rdb$database
+```
+
 ```
 execute procedure insert_customer(
   last_name => 'SCHUMACHER',

src/dsql/ExprNodes.cpp

@@ -13087,12 +13087,15 @@ DmlNode* UdfCallNode::parse(thread_db* tdbb, MemoryPool& pool, CompilerScratch*
 
 	for (auto& parameter : node->function->getInputFields())
 	{
-		if (const auto argValue = argsByName.get(parameter->prm_name))
+		const auto argValue = argsByName.get(parameter->prm_name);
+
+		if (argValue)
 		{
 			*argIt = *argValue;
 			argsByName.remove(parameter->prm_name);
 		}
-		else
+
+		if (!argValue || !*argValue)
 		{
 			if (parameter->prm_default_value)
 				*argIt = CMP_clone_node(tdbb, csb, parameter->prm_default_value);
@@ -13185,7 +13188,7 @@ void UdfCallNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 		dsqlScratch->appendUShort(args->items.getCount());
 
 		for (auto& arg : args->items)
-			GEN_expr(dsqlScratch, arg);
+			GEN_arg(dsqlScratch, arg);
 
 		dsqlScratch->appendUChar(blr_end);
 
@@ -13204,7 +13207,7 @@ void UdfCallNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 	dsqlScratch->appendUChar(args->items.getCount());
 
 	for (auto& arg : args->items)
-		GEN_expr(dsqlScratch, arg);
+		GEN_arg(dsqlScratch, arg);
 }
 
 void UdfCallNode::make(DsqlCompilerScratch* /*dsqlScratch*/, dsc* desc)

src/dsql/StmtNodes.cpp

@@ -3430,7 +3430,7 @@ void ExecProcedureNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 			dsqlScratch->appendUShort(inputSources->items.getCount());
 
 			for (auto& arg : inputSources->items)
-				GEN_expr(dsqlScratch, arg);
+				GEN_arg(dsqlScratch, arg);
 		}
 
 		// Output parameters.
@@ -3461,11 +3461,9 @@ void ExecProcedureNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 		if (inputSources)
 		{
 			dsqlScratch->appendUShort(inputSources->items.getCount());
-			auto ptr = inputSources->items.begin();
-			const auto end = inputSources->items.end();
 
-			while (ptr < end)
+			for (auto& arg : inputSources->items)
-				GEN_expr(dsqlScratch, *ptr++);
+				GEN_arg(dsqlScratch, arg);
 		}
 		else
 			dsqlScratch->appendUShort(0);
@@ -3474,10 +3472,9 @@ void ExecProcedureNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 		if (outputSources)
 		{
 			dsqlScratch->appendUShort(outputSources->items.getCount());
-			auto ptr = outputSources->items.begin();
 
-			for (const auto end = outputSources->items.end(); ptr != end; ++ptr)
+			for (auto& arg : outputSources->items)
-				GEN_expr(dsqlScratch, *ptr);
+				GEN_expr(dsqlScratch, arg);
 		}
 		else
 			dsqlScratch->appendUShort(0);

src/dsql/gen.cpp

@@ -65,6 +65,17 @@ using namespace Firebird;
 static void gen_plan(DsqlCompilerScratch*, const PlanNode*);
 
 
+// Generate blr for an argument.
+// When it is nullptr, generate blr_default_arg.
+void GEN_arg(DsqlCompilerScratch* dsqlScratch, ExprNode* node)
+{
+	if (node)
+		GEN_expr(dsqlScratch, node);
+	else
+		dsqlScratch->appendUChar(blr_default_arg);
+}
+
+
 void GEN_hidden_variables(DsqlCompilerScratch* dsqlScratch)
 {
 /**************************************

src/dsql/gen_proto.h

@@ -30,6 +30,7 @@ namespace Jrd
 	class ValueListNode;
 }
 
+void	GEN_arg(Jrd::DsqlCompilerScratch*, Jrd::ExprNode*);
 void	GEN_descriptor(Jrd::DsqlCompilerScratch* dsqlScratch, const dsc* desc, bool texttype);
 void	GEN_expr(Jrd::DsqlCompilerScratch*, Jrd::ExprNode*);
 void	GEN_hidden_variables(Jrd::DsqlCompilerScratch* dsqlScratch);

src/dsql/parse.y

@@ -8618,12 +8618,12 @@ argument_list_opt
 %type <namedArguments> argument_list
 argument_list
 	: named_argument_list
-	| value_list
+	| value_or_default_list
 		{
 			$$ = newNode<NonPooledPair<ObjectsArray<MetaName>*, ValueListNode*>>();
 			$$->second = $1;
 		}
-	| value_list ',' named_argument_list
+	| value_or_default_list ',' named_argument_list
 		{
 			$$ = $3;
 
@@ -8655,7 +8655,7 @@ named_argument_list
 
 %type <namedArgument> named_argument
 named_argument
-	: symbol_column_name NAMED_ARG_ASSIGN value
+	: symbol_column_name NAMED_ARG_ASSIGN value_or_default
 		{ $$ = newNode<NonPooledPair<MetaName*, ValueExprNode*>>($1, $3); }
 	;
 

src/include/firebird/impl/blr.h

@@ -492,4 +492,6 @@
 #define blr_invsel_procedure_context				(unsigned char) 6
 #define blr_invsel_procedure_alias					(unsigned char) 7
 
+#define blr_default_arg								(unsigned char) 227
+
 #endif // FIREBIRD_IMPL_BLR_H

src/include/firebird/impl/msg/jrd.h

@@ -970,5 +970,5 @@ FB_IMPL_MSG(JRD, 967, idx_expr_not_found, -902, "42", "000", "Definition of inde
 FB_IMPL_MSG(JRD, 968, idx_cond_not_found, -902, "42", "000", "Definition of index condition is not found for index @1")
 FB_IMPL_MSG(JRD, 969, uninitialized_var, -625, "42", "000", "Variable @1 is not initialized")
 FB_IMPL_MSG(JRD, 970, param_not_exist, -170, "07", "001", "Parameter @1 does not exist")
-FB_IMPL_MSG(JRD, 971, param_no_default_not_specified, -170, "07", "001", "Parameter @1 has no default value and was not specified")
+FB_IMPL_MSG(JRD, 971, param_no_default_not_specified, -170, "07", "001", "Parameter @1 has no default value and was not specified or was specified with DEFAULT")
 FB_IMPL_MSG(JRD, 972, param_multiple_assignments, -170, "07", "001", "Parameter @1 has multiple assignments")

src/jrd/RecordSourceNodes.cpp

@@ -1294,7 +1294,7 @@ void ProcedureSourceNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 			dsqlScratch->appendUShort(inputSources->items.getCount());
 
 			for (auto& arg : inputSources->items)
-				GEN_expr(dsqlScratch, arg);
+				GEN_arg(dsqlScratch, arg);
 		}
 
 		if (dsqlContext->ctx_context > MAX_UCHAR)
@@ -1355,7 +1355,7 @@ void ProcedureSourceNode::genBlr(DsqlCompilerScratch* dsqlScratch)
 		dsqlScratch->appendUShort(inputSources->items.getCount());
 
 		for (auto& arg : inputSources->items)
-			GEN_expr(dsqlScratch, arg);
+			GEN_arg(dsqlScratch, arg);
 	}
 	else
 		dsqlScratch->appendUShort(0);

src/jrd/blp.h

@@ -258,5 +258,6 @@ static const struct
 	{"invoke_function", invoke_function},
 	{"invoke_procedure", invsel_procedure},
 	{"select_procedure", invsel_procedure},
+	{"blr_default_arg", zero},
 	{0, 0}
 };

src/jrd/cmp.cpp

@@ -553,12 +553,15 @@ Arg::StatusVector CMP_procedure_arguments(
 
 		for (auto& parameter : fields)
 		{
-			if (const auto argValue = argsByName.get(parameter->prm_name))
+			const auto argValue = argsByName.get(parameter->prm_name);
+
+			if (argValue)
 			{
 				*sourceArgIt = *argValue;
 				argsByName.remove(parameter->prm_name);
 			}
-			else if (isInput)
+
+			if (isInput && (!argValue || !*argValue))
 			{
 				if (parameter->prm_default_value)
 					*sourceArgIt = CMP_clone_node(tdbb, csb, parameter->prm_default_value);

src/jrd/par.cpp

@@ -804,7 +804,12 @@ ValueListNode* PAR_args(thread_db* tdbb, CompilerScratch* csb, USHORT count, USH
 	{
 		do
 		{
-			*ptr++ = PAR_parse_value(tdbb, csb);
+			if (csb->csb_blr_reader.peekByte() == blr_default_arg)
+				csb->csb_blr_reader.getByte();
+			else
+				*ptr = PAR_parse_value(tdbb, csb);
+
+			++ptr;
 		} while (--count);
 	}