Fixed CORE-1837 : Procedure text is stored truncated in system tables…

… if any variable have default value

src/dsql/Parser.h

@@ -26,6 +26,7 @@
 #include "../jrd/common.h"
 #include "../dsql/dsql.h"
 #include "../dsql/node.h"
+#include "../common/classes/stack.h"
 
 namespace Jrd {
 
@@ -65,7 +66,12 @@ class Parser : public Firebird::PermanentStorage
 		int dsql_debug;
 
 		// Actual lexer state begins from here
-		const TEXT* beginning;
+
+		// hvlad: if at some day 16 levels of nesting would be not enough
+		// then someone must add LexerState constructor and pass memory 
+		// pool into Stack's constructor or change Capacity value in template 
+		// instantiation below
+		Firebird::Stack<const TEXT*> beginnings;
 		const TEXT* ptr;
 		const TEXT* end;
 		const TEXT* last_token;

src/dsql/parse.y

@@ -2060,22 +2060,26 @@ alter_view_clause	: symbol_view_name column_parens_opt AS begin_string select_ex
 /* these rules will capture the input string for storage in metadata */
 
 begin_string	: 
-			{ lex.beginning = lex_position(); }
+			{ lex.beginnings.push(lex_position()); }
 		;
 /*
 end_string	:
-			{ $$ = (dsql_nod*) MAKE_string(lex.beginning,
-				   (lex_position() == lex.end) ?
-				   lex_position() - lex.beginning : lex.last_token - lex.beginning);}
+			{ 
+				const TEXT* start = lex.beginnings.pop();
+				$$ = (dsql_nod*) MAKE_string(start, 
+					(lex_position() == lex.end) ? lex_position() - start : lex.last_token - start);
+			}
 		;
 */
 begin_trigger	: 
-			{ lex.beginning = lex.last_token; }
+			{ lex.beginnings.push(lex.last_token); }
 		;
 
 end_trigger	:
-			{ $$ = (dsql_nod*) MAKE_string(lex.beginning,
-					lex_position() - lex.beginning); }
+			{ 
+				const TEXT* start = lex.beginnings.pop();
+				$$ = (dsql_nod*) MAKE_string(start, lex_position() - start); 
+			}
 		;