Merge branch 'main' into bugfix/adjust-mps-structure

pyomo/core/base/units_container.py

@@ -1514,6 +1514,19 @@ def __getattribute__(self, attr):
         # present, at which point this instance __class__ will fall back
         # to PyomoUnitsContainer (where this method is not declared, OR
         # pint is not available and an ImportError will be raised.
+        #
+        # We need special case handling for __class__: gurobipy
+        # interrogates things by looking at their __class__ during
+        # python shutdown.  Unfortunately, interrogating this
+        # singleton's __class__ evaluates `pint_available`, which - if
+        # DASK is installed - imports dask.  Importing dask creates
+        # threading objects.  Unfortunately, creating threading objects
+        # during interpreter shutdown generates a RuntimeError.  So, our
+        # solution is to special-case the resolution of __class__ here
+        # to avoid accidentally triggering the imports.
+        if attr == "__class__":
+            return _DeferredUnitsSingleton
+        #
         if pint_available:
             # If the first thing that is being called is
             # "units.set_pint_registry(...)", then we will call __init__

pyomo/solvers/plugins/solvers/SCIPAMPL.py

@@ -288,115 +288,123 @@ def _postsolve(self):
 
         # UNKNOWN # unknown='unknown' # An uninitialized value
 
-        if results.solver.message == "unknown":
+        if "unknown" in results.solver.message:
             results.solver.status = SolverStatus.unknown
             results.solver.termination_condition = TerminationCondition.unknown
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.unknown
 
         # ABORTED # userInterrupt='userInterrupt' # Interrupt signal generated by user
 
-        elif results.solver.message == "user interrupt":
+        elif "user interrupt" in results.solver.message:
             results.solver.status = SolverStatus.aborted
             results.solver.termination_condition = TerminationCondition.userInterrupt
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.unknown
 
         # OK # maxEvaluations='maxEvaluations' # Exceeded maximum number of problem evaluations
 
-        elif results.solver.message == "node limit reached":
+        elif "node limit reached" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.maxEvaluations
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.stoppedByLimit
 
         # OK # maxEvaluations='maxEvaluations' # Exceeded maximum number of problem evaluations
 
-        elif results.solver.message == "total node limit reached":
+        elif "total node limit reached" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.maxEvaluations
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.stoppedByLimit
 
         # OK # maxEvaluations='maxEvaluations' # Exceeded maximum number of problem evaluations
 
-        elif results.solver.message == "stall node limit reached":
+        elif "stall node limit reached" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.maxEvaluations
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.stoppedByLimit
 
         # OK # maxTimeLimit='maxTimeLimit' # Exceeded maximum time limited allowed by user but having return a feasible solution
 
-        elif results.solver.message == "time limit reached":
+        elif "time limit reached" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.maxTimeLimit
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.stoppedByLimit
 
         # OK # other='other' # Other, uncategorized normal termination
 
-        elif results.solver.message == "memory limit reached":
+        elif "memory limit reached" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.other
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.stoppedByLimit
 
         # OK # other='other' # Other, uncategorized normal termination
 
-        elif results.solver.message == "gap limit reached":
+        elif "gap limit reached" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.other
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.stoppedByLimit
 
         # OK # other='other' # Other, uncategorized normal termination
 
-        elif results.solver.message == "solution limit reached":
+        elif "solution limit reached" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.other
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.stoppedByLimit
 
         # OK # other='other' # Other, uncategorized normal termination
 
-        elif results.solver.message == "solution improvement limit reached":
+        elif "solution improvement limit reached" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.other
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.stoppedByLimit
 
         # OK # optimal='optimal' # Found an optimal solution
 
-        elif results.solver.message == "optimal solution found":
+        elif "optimal solution" in results.solver.message:
             results.solver.status = SolverStatus.ok
             results.solver.termination_condition = TerminationCondition.optimal
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.optimal
-            if results.problem.sense == ProblemSense.minimize:
-                results.problem.lower_bound = results.solver.primal_bound
-            else:
-                results.problem.upper_bound = results.solver.primal_bound
+            try:
+                if results.problem.sense == ProblemSense.minimize:
+                    results.problem.lower_bound = results.solver.primal_bound
+                else:
+                    results.problem.upper_bound = results.solver.primal_bound
+            except AttributeError:
+                """
+                This may occur if SCIP solves the problem during presolve. In that case,
+                the log file may not get parsed correctly (self.read_scip_log), and
+                results.solver.primal_bound will not be populated.
+                """
+                pass
 
         # WARNING # infeasible='infeasible' # Demonstrated that the problem is infeasible
 
-        elif results.solver.message == "infeasible":
+        elif "infeasible" in results.solver.message:
             results.solver.status = SolverStatus.warning
             results.solver.termination_condition = TerminationCondition.infeasible
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.infeasible
 
         # WARNING # unbounded='unbounded' # Demonstrated that problem is unbounded
 
-        elif results.solver.message == "unbounded":
+        elif "unbounded" in results.solver.message:
             results.solver.status = SolverStatus.warning
             results.solver.termination_condition = TerminationCondition.unbounded
             if len(results.solution) > 0:
                 results.solution(0).status = SolutionStatus.unbounded
 
         # WARNING # infeasibleOrUnbounded='infeasibleOrUnbounded'   # Problem is either infeasible or unbounded
 
-        elif results.solver.message == "infeasible or unbounded":
+        elif "infeasible or unbounded" in results.solver.message:
             results.solver.status = SolverStatus.warning
             results.solver.termination_condition = (
                 TerminationCondition.infeasibleOrUnbounded