lalr1.cc: check (and fix) %printer exception safety

* tests/c++.at (Exception safety): Let the parser support the --debug
option.
On 'p', throw an exception from the %printer.
* data/lalr1.cc (yyparse): Do not display the values we discard, as it
uses %printer, which might have thrown the exception.
This commit is contained in:
Akim Demaille
2012-09-25 11:41:22 +02:00
parent a26424642b
commit 25a6ad2f10
2 changed files with 44 additions and 17 deletions

View File

@@ -203,11 +203,14 @@ AT_DATA_GRAMMAR([[input.yy]],
int debug = 0;
/// A class that counts its number of instances.
struct Object
{
static size_t counter;
int val;
Object ()
Object (int v)
: val (v)
{
++counter;
if (debug)
@@ -245,9 +248,14 @@ AT_DATA_GRAMMAR([[input.yy]],
}
%destructor { delete $$; } <obj>;
%printer { yyo << "counter == " << $$->counter; } <obj>;
%printer
{
yyo << "counter == " << $$->counter;
if ($$->val == 'p')
throw std::runtime_error ("printer");
} <obj>;
%token <obj> 'a' 's'
%token <obj> 'a' 'p' 's'
%type <obj> list item
%%
@@ -256,14 +264,12 @@ start: list { delete $1; };
list:
item { $$ = $1; }
| item list { $$ = $1; delete $2; } /* Right recursion to load the stack. */
| item list { $$ = $1; delete $2; } // Right recursion to load the stack.
;
item:
'a'
{
std::swap ($$, $1);
}
'a' { std::swap ($$, $1); }
| 'p' { std::swap ($$, $1); }
| 's'
{
std::swap ($$, $1);
@@ -284,7 +290,7 @@ yylex (yy::parser::semantic_type *lvalp)
case 'l':
throw std::runtime_error ("yylex");
default:
lvalp->obj = new Object;
lvalp->obj = new Object (res);
// Fall through.
case 0:
return res;
@@ -296,10 +302,22 @@ yylex (yy::parser::semantic_type *lvalp)
int
main (int argc, const char *argv[])
{
assert (argc == 2);
input = argv[1];
switch (argc)
{
case 2:
input = argv[1];
break;
case 3:
assert (!strcmp (argv[1], "--debug"));
debug = 1;
input = argv[2];
break;
default:
abort ();
}
yy::parser parser;
debug = !!getenv ("YYDEBUG");
debug |= !!getenv ("YYDEBUG");
parser.set_debug_level (debug);
int res = 2;
try
@@ -333,6 +351,11 @@ AT_PARSER_CHECK([[./input i]], [[2]], [[]],
[[exception caught: initial-action
]])
AT_PARSER_CHECK([[./input aaaap]])
AT_PARSER_CHECK([[./input --debug aaaap]], [[2]], [[]], [[stderr]])
AT_PARSER_CHECK([[grep '^exception caught: printer$' stderr]], [], [ignore])
AT_BISON_OPTION_POPDEFS
AT_CLEANUP