From a41cffe3d59210ca8ea0ac3b0950a14b7ce26a31 Mon Sep 17 00:00:00 2001
From: Alex Lindsay <alexlindsay239@gmail.com>
Date: Wed, 2 Feb 2022 12:34:16 -0800
Subject: [PATCH] Support mortar meshes without corresponding mortar
 constraints

Closes #20214
---
 .../include/constraints/ConstraintWarehouse.h |  3 +-
 .../src/constraints/ConstraintWarehouse.C     | 10 ++++-
 framework/src/systems/NonlinearSystemBase.C   | 40 ++++++-------------
 3 files changed, 23 insertions(+), 30 deletions(-)

diff --git a/framework/include/constraints/ConstraintWarehouse.h b/framework/include/constraints/ConstraintWarehouse.h
index 865b79fa9ead..f33517d3f8fc 100644
--- a/framework/include/constraints/ConstraintWarehouse.h
+++ b/framework/include/constraints/ConstraintWarehouse.h
@@ -57,6 +57,8 @@ class ConstraintWarehouse : public MooseObjectWarehouse<Constraint>
    * Deterimine if active objects exist.
    */
   bool hasActiveNodalConstraints() const;
+  bool hasActiveMortarConstraints(const std::pair<BoundaryID, BoundaryID> & mortar_interface_key,
+                                  bool displaced) const;
   bool hasActiveElemElemConstraints(const InterfaceID interface_id, bool displaced) const;
   bool hasActiveNodeFaceConstraints(BoundaryID boundary_id, bool displaced) const;
   bool hasActiveNodeElemConstraints(SubdomainID secondary_id,
@@ -110,4 +112,3 @@ class ConstraintWarehouse : public MooseObjectWarehouse<Constraint>
   std::map<std::pair<SubdomainID, SubdomainID>, MooseObjectWarehouse<NodeElemConstraint>>
       _displaced_node_elem_constraints;
 };
-
diff --git a/framework/src/constraints/ConstraintWarehouse.C b/framework/src/constraints/ConstraintWarehouse.C
index 1737e5675423..8bfa53feb3a9 100644
--- a/framework/src/constraints/ConstraintWarehouse.C
+++ b/framework/src/constraints/ConstraintWarehouse.C
@@ -131,9 +131,17 @@ ConstraintWarehouse::getActiveNodeFaceConstraints(BoundaryID boundary_id, bool d
   return it->second.getActiveObjects();
 }
 
+bool
+ConstraintWarehouse::hasActiveMortarConstraints(
+    const std::pair<BoundaryID, BoundaryID> & mortar_interface_key, const bool displaced) const
+{
+  const auto & constraints = displaced ? _displaced_mortar_constraints : _mortar_constraints;
+  return constraints.find(mortar_interface_key) != constraints.end();
+}
+
 const std::vector<std::shared_ptr<MortarConstraintBase>> &
 ConstraintWarehouse::getActiveMortarConstraints(
-    const std::pair<BoundaryID, BoundaryID> & mortar_interface_key, bool displaced) const
+    const std::pair<BoundaryID, BoundaryID> & mortar_interface_key, const bool displaced) const
 {
   std::map<std::pair<BoundaryID, BoundaryID>,
            MooseObjectWarehouse<MortarConstraintBase>>::const_iterator it,
diff --git a/framework/src/systems/NonlinearSystemBase.C b/framework/src/systems/NonlinearSystemBase.C
index 318bb4def41c..ed490fa96949 100644
--- a/framework/src/systems/NonlinearSystemBase.C
+++ b/framework/src/systems/NonlinearSystemBase.C
@@ -294,7 +294,10 @@ NonlinearSystemBase::initialSetup()
         _fe_problem.getMortarInterfaces(/*displaced=*/false);
     for (const auto & mortar_interface : undisplaced_mortar_interfaces)
     {
-      auto primary_secondary_boundary_pair = mortar_interface.first;
+      const auto primary_secondary_boundary_pair = mortar_interface.first;
+      if (!_constraints.hasActiveMortarConstraints(primary_secondary_boundary_pair, false))
+        continue;
+
       const auto & mortar_generation_object = mortar_interface.second;
 
       auto & mortar_constraints = _constraints.getActiveMortarConstraints(
@@ -313,7 +316,10 @@ NonlinearSystemBase::initialSetup()
     {
       mooseAssert(_fe_problem.getDisplacedProblem(),
                   "Cannot create displaced mortar functors when the displaced problem is null");
-      auto primary_secondary_boundary_pair = mortar_interface.first;
+      const auto primary_secondary_boundary_pair = mortar_interface.first;
+      if (!_constraints.hasActiveMortarConstraints(primary_secondary_boundary_pair, true))
+        continue;
+
       const auto & mortar_generation_object = mortar_interface.second;
 
       auto & mortar_constraints = _constraints.getActiveMortarConstraints(
@@ -3311,33 +3317,11 @@ NonlinearSystemBase::setPreviousNewtonSolution(const NumericVector<Number> & sol
 void
 NonlinearSystemBase::mortarConstraints()
 {
-  const auto & undisplaced_mortar_interfaces = _fe_problem.getMortarInterfaces(/*displaced=*/false);
-
-  for (const auto & mortar_interface : undisplaced_mortar_interfaces)
-  {
-    auto it = _undisplaced_mortar_functors.find(mortar_interface.first);
+  for (auto & map_pr : _undisplaced_mortar_functors)
+    map_pr.second();
 
-    mooseAssert(it != _undisplaced_mortar_functors.end(),
-                "No ComputeMortarFunctor exists for the specified primary-secondary boundary "
-                "pair, primary "
-                    << mortar_interface.first.first << " and secondary "
-                    << mortar_interface.first.second);
-    it->second();
-  }
-
-  const auto & displaced_mortar_interfaces = _fe_problem.getMortarInterfaces(/*displaced=*/true);
-
-  for (const auto & mortar_interface : displaced_mortar_interfaces)
-  {
-    auto it = _displaced_mortar_functors.find(mortar_interface.first);
-
-    mooseAssert(it != _displaced_mortar_functors.end(),
-                "No ComputeMortarFunctor exists for the specified primary-secondary boundary "
-                "pair, primary "
-                    << mortar_interface.first.first << " and secondary "
-                    << mortar_interface.first.second);
-    it->second();
-  }
+  for (auto & map_pr : _displaced_mortar_functors)
+    map_pr.second();
 }
 
 void