LP writer dies given a Var with an empty domain

[emma58]

Summary

If I create a Var that has an empty domain created by intersecting Binary and $\{2, 3\}$ (the model is structurally infeasible), the LP writer croaks somewhere in figuring out the domain (I think).

Steps to reproduce the issue

from pyomo.environ import *

m = ConcreteModel()
m.thing = Set(initialize=[2, 3])
m.x = Var(domain=Binary & m.thing)

m.c = Constraint(expr=m.x >= 0.5)

m.obj = Objective(expr=m.x)

SolverFactory('gurobi').solve(m, tee=True)

Error Message

Traceback (most recent call last):
  File "/home/esjohn/src/pyomo/pyomo/core/base/set.py", line 729, in _get_discrete_interval
    step = min(abs(r.step) for r in ranges if r.step != 0)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: min() arg is an empty sequence

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/esjohn/src/pyomo/just_checking.py", line 11, in <module>
    SolverFactory('gurobi').solve(m, tee=True)
  File "/home/esjohn/src/pyomo/pyomo/opt/base/solvers.py", line 598, in solve
    self._presolve(*args, **kwds)
  File "/home/esjohn/src/pyomo/pyomo/solvers/plugins/solvers/GUROBI.py", line 249, in _presolve
    ILMLicensedSystemCallSolver._presolve(self, *args, **kwds)
  File "/home/esjohn/src/pyomo/pyomo/opt/solver/shellcmd.py", line 223, in _presolve
    OptSolver._presolve(self, *args, **kwds)
  File "/home/esjohn/src/pyomo/pyomo/opt/base/solvers.py", line 704, in _presolve
    self._convert_problem(
  File "/home/esjohn/src/pyomo/pyomo/opt/base/solvers.py", line 756, in _convert_problem
    return convert_problem(
           ^^^^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/opt/base/convert.py", line 97, in convert_problem
    problem_files, symbol_map = converter.apply(*tmp, **tmpkw)
                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/solvers/plugins/converter/model.py", line 78, in apply
    (problem_filename, symbol_map_id) = instance.write(
                                        ^^^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/core/base/block.py", line 1940, in write
    (filename, smap) = problem_writer(self, filename, solver_capability, io_options)
                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/repn/plugins/lp_writer.py", line 208, in __call__
    info = self.write(model, FILE, **io_options)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/repn/plugins/lp_writer.py", line 241, in write
    return _LPWriter_impl(ostream, config).write(model)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/repn/plugins/lp_writer.py", line 522, in write
    if v.is_binary():
       ^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/core/base/var.py", line 190, in is_binary
    return domain.get_interval() == (0, 1, 1)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/core/base/set.py", line 704, in get_interval
    return self._get_discrete_interval()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/esjohn/src/pyomo/pyomo/core/base/set.py", line 738, in _get_discrete_interval
    return (vals[0], vals[0], 0)
            ~~~~^^^
IndexError: list index out of range

Information on your system

Pyomo version: main
Python version: 3.11
Operating system:
How Pyomo was installed (PyPI, conda, source):
Solver (if applicable):