Merge branch 'main' into empty_blocks

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,3 +1,12 @@
+<!-- ##################################################################### -->
+<!-- PLEASE READ BEFORE OPENING THIS PULL REQUEST -->
+
+<!-- All changes must adhere to PEP8 standards as enforced by Black. -->
+<!-- If your changes do NOT adhere, the test suite will fail. -->
+<!-- Please read our Contributing guide for instructions on how to apply these standards. -->
+<!-- Contributing Guide: https://pyomo.readthedocs.io/en/stable/contribution_guide.html -->
+<!-- ##################################################################### -->
+
 ## Fixes # .
 
 ## Summary/Motivation:

pyomo/contrib/appsi/base.py

@@ -900,7 +900,7 @@ def invalidate(self):
 
 
 class PersistentBase(abc.ABC):
-    def __init__(self, only_child_vars=True):
+    def __init__(self, only_child_vars=False):
         self._model = None
         self._active_constraints = dict()  # maps constraint to (lower, body, upper)
         self._vars = dict()  # maps var id to (var, lb, ub, fixed, domain, value)
@@ -1334,9 +1334,6 @@ def update(self, timer: HierarchicalTimer = None):
         self.remove_constraints(old_cons)
         self.remove_sos_constraints(old_sos)
         timer.stop('cons')
-        timer.start('vars')
-        self.remove_variables(old_vars)
-        timer.stop('vars')
         timer.start('params')
         self.remove_params(old_params)
 
@@ -1463,6 +1460,12 @@ def update(self, timer: HierarchicalTimer = None):
             self.set_objective(pyomo_obj)
         timer.stop('objective')
 
+        # this has to be done after the objective and constraints in case the
+        # old objective/constraints use old variables
+        timer.start('vars')
+        self.remove_variables(old_vars)
+        timer.stop('vars')
+
 
 legacy_termination_condition_map = {
     TerminationCondition.unknown: LegacyTerminationCondition.unknown,

pyomo/contrib/appsi/solvers/cbc.py

@@ -64,7 +64,7 @@ def __init__(
 
 
 class Cbc(PersistentSolver):
-    def __init__(self, only_child_vars=True):
+    def __init__(self, only_child_vars=False):
         self._config = CbcConfig()
         self._solver_options = dict()
         self._writer = LPWriter(only_child_vars=only_child_vars)

pyomo/contrib/appsi/solvers/cplex.py

@@ -67,7 +67,7 @@ def __init__(self, solver):
 class Cplex(PersistentSolver):
     _available = None
 
-    def __init__(self, only_child_vars=True):
+    def __init__(self, only_child_vars=False):
         self._config = CplexConfig()
         self._solver_options = dict()
         self._writer = LPWriter(only_child_vars=only_child_vars)

pyomo/contrib/appsi/solvers/gurobi.py

@@ -232,7 +232,7 @@ class Gurobi(PersistentBase, PersistentSolver):
     _available = None
     _num_instances = 0
 
-    def __init__(self, only_child_vars=True):
+    def __init__(self, only_child_vars=False):
         super(Gurobi, self).__init__(only_child_vars=only_child_vars)
         self._num_instances += 1
         self._config = GurobiConfig()

pyomo/contrib/appsi/solvers/highs.py

@@ -144,7 +144,7 @@ class Highs(PersistentBase, PersistentSolver):
 
     _available = None
 
-    def __init__(self, only_child_vars=True):
+    def __init__(self, only_child_vars=False):
         super().__init__(only_child_vars=only_child_vars)
         self._config = HighsConfig()
         self._solver_options = dict()

pyomo/contrib/appsi/solvers/ipopt.py

@@ -127,7 +127,7 @@ def __init__(
 
 
 class Ipopt(PersistentSolver):
-    def __init__(self, only_child_vars=True):
+    def __init__(self, only_child_vars=False):
         self._config = IpoptConfig()
         self._solver_options = dict()
         self._writer = NLWriter(only_child_vars=only_child_vars)

pyomo/contrib/appsi/solvers/tests/test_gurobi_persistent.py

@@ -373,6 +373,7 @@ def test_quadratic_constraint_attr(self):
     def test_var_attr(self):
         m = pe.ConcreteModel()
         m.x = pe.Var(within=pe.Binary)
+        m.obj = pe.Objective(expr=m.x)
 
         opt = Gurobi()
         opt.set_instance(m)
@@ -694,6 +695,8 @@ def test_update7(self):
         m.y = pe.Var()
 
         opt = self.opt
+        orig_only_child_vars = opt._only_child_vars
+        opt._only_child_vars = True
         opt.set_instance(m)
         self.assertEqual(opt._solver_model.getAttr('NumVars'), 2)
 
@@ -712,3 +715,4 @@ def test_update7(self):
         opt.remove_variables([m.x])
         opt.update()
         self.assertEqual(opt._solver_model.getAttr('NumVars'), 1)
+        opt._only_child_vars = orig_only_child_vars