[Depends on #3762] Fix KNITRO tee

pyomo/contrib/solver/solvers/knitro/base.py

@@ -82,7 +82,7 @@ def solve(self, model: BlockData, **kwds) -> Results:
         if config.restore_variable_values_after_solve:
             self._save_var_values()
 
-        with capture_output(TeeStream(self._stream, *config.tee), capture_fd=False):
+        with capture_output(TeeStream(self._stream, *config.tee), capture_fd=True):
             self._solve(config, timer)
 
         if config.restore_variable_values_after_solve:
@@ -268,4 +268,6 @@ def _get_error_type(
             return NoReducedCostsError
         elif item_type is ConstraintData and value_type == ValueType.DUAL:
             return NoDualsError
-        raise DeveloperError()
+        raise DeveloperError(
+            f"Unsupported KNITRO item type {item_type} and value type {value_type}."
+        )

pyomo/contrib/solver/solvers/knitro/config.py

@@ -35,7 +35,13 @@ def __init__(
             ConfigValue(
                 domain=Bool,
                 default=False,
-                doc="KNITRO solver does not allow variable removal. We can either make the variable a continuous free variable or rebuild the whole model when variable removal is attempted. When `rebuild_model_on_remove_var` is set to True, the model will be rebuilt.",
+                doc=(
+                    "KNITRO solver does not allow variable removal. We can "
+                    "either make the variable a continuous free variable or "
+                    "rebuild the whole model when variable removal is "
+                    "attempted. When `rebuild_model_on_remove_var` is set to "
+                    "True, the model will be rebuilt."
+                ),
             ),
         )
 
@@ -44,6 +50,11 @@ def __init__(
             ConfigValue(
                 domain=Bool,
                 default=False,
-                doc="To evaluate non-linear constraints, KNITRO solver sets explicit values on variables. This option controls whether to restore the original variable values after solving.",
+                doc=(
+                    "To evaluate non-linear constraints, KNITRO solver sets "
+                    "explicit values on variables. This option controls "
+                    "whether to restore the original variable values after "
+                    "solving."
+                ),
             ),
         )

pyomo/contrib/solver/solvers/knitro/engine.py

@@ -44,18 +44,20 @@ def parse_bounds(
             if item.fixed:
                 bounds_map[BoundType.EQ][i] = value(item.value)
                 continue
-            if item.has_lb():
-                bounds_map[BoundType.LO][i] = value(item.lb)
-            if item.has_ub():
-                bounds_map[BoundType.UP][i] = value(item.ub)
+            lb, ub = item.bounds
+            if lb is not None:
+                bounds_map[BoundType.LO][i] = lb
+            if ub is not None:
+                bounds_map[BoundType.UP][i] = ub
         elif isinstance(item, ConstraintData):
+            lb, _, ub = item.to_bounded_expression(evaluate_bounds=True)
             if item.equality:
-                bounds_map[BoundType.EQ][i] = value(item.lower)
+                bounds_map[BoundType.EQ][i] = lb
                 continue
-            if item.has_lb():
-                bounds_map[BoundType.LO][i] = value(item.lower)
-            if item.has_ub():
-                bounds_map[BoundType.UP][i] = value(item.upper)
+            if lb is not None:
+                bounds_map[BoundType.LO][i] = lb
+            if ub is not None:
+                bounds_map[BoundType.UP][i] = ub
     return bounds_map
 
 
@@ -85,7 +87,7 @@ def api_set_param(param_type: int) -> Callable[..., None]:
         return knitro.KN_set_double_param
     elif param_type == knitro.KN_PARAMTYPE_STRING:
         return knitro.KN_set_char_param
-    raise DeveloperError()
+    raise DeveloperError(f"Unsupported KNITRO parameter type: {param_type}")
 
 
 def api_get_values(
@@ -101,15 +103,17 @@ def api_get_values(
             return knitro.KN_get_con_dual_values
         elif value_type == ValueType.PRIMAL:
             return knitro.KN_get_con_values
-    raise DeveloperError()
+    raise DeveloperError(
+        f"Unsupported KNITRO item type or value type: {item_type}, {value_type}"
+    )
 
 
 def api_add_items(item_type: type[ItemType]) -> Callable[..., Optional[list[int]]]:
     if item_type is VarData:
         return knitro.KN_add_vars
     elif item_type is ConstraintData:
         return knitro.KN_add_cons
-    raise DeveloperError()
+    raise DeveloperError(f"Unsupported KNITRO item type: {item_type}")
 
 
 def api_set_bnds(
@@ -129,13 +133,15 @@ def api_set_bnds(
             return knitro.KN_set_con_lobnds
         elif bound_type == BoundType.UP:
             return knitro.KN_set_con_upbnds
-    raise DeveloperError()
+    raise DeveloperError(
+        f"Unsupported KNITRO item type or bound type: {item_type}, {bound_type}"
+    )
 
 
 def api_set_types(item_type: type[ItemType]) -> Callable[..., None]:
     if item_type is VarData:
         return knitro.KN_set_var_types
-    raise DeveloperError()
+    raise DeveloperError(f"Unsupported KNITRO item type: {item_type}")
 
 
 def api_add_struct(is_obj: bool, structure_type: StructureType) -> Callable[..., None]:
@@ -153,7 +159,9 @@ def api_add_struct(is_obj: bool, structure_type: StructureType) -> Callable[...,
             return knitro.KN_add_con_linear_struct
         elif structure_type == StructureType.QUADRATIC:
             return knitro.KN_add_con_quadratic_struct
-    raise DeveloperError()
+    raise DeveloperError(
+        f"Unsupported KNITRO structure type: is_obj={is_obj}, structure_type={structure_type}"
+    )
 
 
 class Engine:

pyomo/contrib/solver/solvers/knitro/utils.py

@@ -18,6 +18,7 @@
 from pyomo.contrib.solver.solvers.knitro.typing import Function
 from pyomo.core.base.block import BlockData
 from pyomo.core.base.constraint import Constraint, ConstraintData
+from pyomo.core.base.enums import SortComponents
 from pyomo.core.base.expression import Expression
 from pyomo.core.base.objective import Objective, ObjectiveData
 from pyomo.core.base.var import VarData
@@ -51,7 +52,7 @@ def get_active_constraints(block: BlockData) -> list[ConstraintData]:
 
     """
     generator = block.component_data_objects(
-        Constraint, descend_into=True, active=True, sort=True
+        Constraint, descend_into=True, active=True, sort=SortComponents.deterministic
     )
     return list(generator)
 

pyomo/contrib/solver/tests/solvers/test_knitro_direct.py

@@ -9,6 +9,9 @@
 #  This software is distributed under the 3-clause BSD License.
 #  ___________________________________________________________________________
 
+import io
+from contextlib import redirect_stdout
+
 import pyomo.common.unittest as unittest
 
 from pyomo.contrib.solver.solvers.knitro.config import KnitroConfig
@@ -87,6 +90,32 @@ class TestKnitroDirectSolver(unittest.TestCase):
     def setUp(self):
         self.opt = KnitroDirectSolver()
 
+    def test_solve_tee(self):
+        m = pyo.ConcreteModel()
+        m.x = pyo.Var(initialize=1.5, bounds=(-5, 5))
+        m.y = pyo.Var(initialize=1.5, bounds=(-5, 5))
+        m.obj = pyo.Objective(
+            expr=(1.0 - m.x) + 100.0 * (m.y - m.x), sense=pyo.minimize
+        )
+        stream = io.StringIO()
+        with redirect_stdout(stream):
+            self.opt.solve(m, tee=True)
+        output = stream.getvalue()
+        self.assertTrue(bool(output.strip()))
+
+    def test_solve_no_tee(self):
+        m = pyo.ConcreteModel()
+        m.x = pyo.Var(initialize=1.5, bounds=(-5, 5))
+        m.y = pyo.Var(initialize=1.5, bounds=(-5, 5))
+        m.obj = pyo.Objective(
+            expr=(1.0 - m.x) + 100.0 * (m.y - m.x), sense=pyo.minimize
+        )
+        stream = io.StringIO()
+        with redirect_stdout(stream):
+            self.opt.solve(m, tee=False)
+        output = stream.getvalue()
+        self.assertFalse(bool(output.strip()))
+
     def test_solve(self):
         m = pyo.ConcreteModel()
         m.x = pyo.Var(initialize=1.5, bounds=(-5, 5))