Maximum recursion depth exceeded when dumping a large Finite State Machines

[cheuberg]

When calling dumps(fsm) for some large finite state machine, maximum recursion depth might be exceeded:

  File "sage/misc/persist.pyx", line 285, in sage.misc.persist.dumps (build/cythonized/sage/misc/persist.c:4397)
  File "sage/misc/persist.pyx", line 256, in sage.misc.persist._base_dumps (build/cythonized/sage/misc/persist.c:3989)
  File "sage/misc/persist.pyx", line 835, in sage.misc.persist.SagePickler.dumps (build/cythonized/sage/misc/persist.c:6593)
  File "sage/misc/persist.pyx", line 592, in sage.misc.persist._BasePickler.dump (build/cythonized/sage/misc/persist.c:5664)
RuntimeError: maximum recursion depth exceeded while calling a Python object

CC: @dkrenn

Component: finite state machines

Keywords: Pickle

Author: Clemens Heuberger

Branch/Commit: ef2d7a6

Reviewer: Daniel Krenn

Issue created by migration from https://trac.sagemath.org/ticket/26491

[cheuberg]

comment:1

I guess that the problem is that states save their outgoing transitions. So a dump will be recursive, because one state dumps its transitions which in turn dump their states and so on.

[cheuberg]

Commit: ef2d7a6

[cheuberg]

Changed keywords from none to Pickle

[cheuberg]

Author: Clemens Heuberger

[cheuberg]

New commits:

ef2d7a6

Trac #26491: Pickle Finite State Machines

[cheuberg]

Branch: u/cheuberg/t/26491/pickle-fsm

[dkrenn]

Reviewer: Daniel Krenn

[dkrenn]

comment:3

LGTM (positive review) modulo patchbot (which has not finished yet).

[vbraun]

Changed branch from u/cheuberg/t/26491/pickle-fsm to ef2d7a6

[embray]

comment:6

This should be re-targeted for 8.5.