Fix for SF bug 1569998: break permitted inside try.

The compiler was checking that there was something on the fblock
stack, but not that there was a loop on the stack.  Fixed that and
added a test for the specific syntax error.

Bug fix candidate.
This commit is contained in:
Jeremy Hylton 2006-10-04 02:24:52 +00:00
parent 1e3c3b15df
commit 82271f13e7
2 changed files with 27 additions and 1 deletions

View File

@ -322,6 +322,20 @@ This is essentially a continue in a finally which should not be allowed.
...
SyntaxError: 'continue' not supported inside 'finally' clause (<doctest test.test_syntax[41]>, line 8)
There is one test for a break that is not in a loop. The compiler
uses a single data structure to keep track of try-finally and loops,
so we need to be sure that a break is actually inside a loop. If it
isn't, there should be a syntax error.
>>> try:
... print 1
... break
... print 2
... finally:
... print 3
Traceback (most recent call last):
...
SyntaxError: 'break' outside loop (<doctest test.test_syntax[42]>, line 3)
"""
import re

View File

@ -187,6 +187,8 @@ static int compiler_push_fblock(struct compiler *, enum fblocktype,
basicblock *);
static void compiler_pop_fblock(struct compiler *, enum fblocktype,
basicblock *);
/* Returns true if there is a loop on the fblock stack. */
static int compiler_in_loop(struct compiler *);
static int inplace_binop(struct compiler *, operator_ty);
static int expr_constant(expr_ty e);
@ -2157,7 +2159,7 @@ compiler_visit_stmt(struct compiler *c, stmt_ty s)
case Pass_kind:
break;
case Break_kind:
if (!c->u->u_nfblocks)
if (!compiler_in_loop(c))
return compiler_error(c, "'break' outside loop");
ADDOP(c, BREAK_LOOP);
break;
@ -3147,6 +3149,16 @@ compiler_pop_fblock(struct compiler *c, enum fblocktype t, basicblock *b)
assert(u->u_fblock[u->u_nfblocks].fb_block == b);
}
static int
compiler_in_loop(struct compiler *c) {
int i;
struct compiler_unit *u = c->u;
for (i = 0; i < u->u_nfblocks; ++i) {
if (u->u_fblock[i].fb_type == LOOP)
return 1;
}
return 0;
}
/* Raises a SyntaxError and returns 0.
If something goes wrong, a different exception may be raised.
*/