feat: enable mixed models (#1645)

This PR finally enables the coexistence of basic and list variables in the same model.

Author: zepfred

core/src/main/java/ai/timefold/solver/core/config/heuristic/selector/move/NearbyAutoConfigurationEnabled.java

@@ -11,6 +11,11 @@
  */
 public interface NearbyAutoConfigurationEnabled<Config_ extends MoveSelectorConfig<Config_>> {
 
+    /**
+     * @return true if it can enable the nearby setting for the given move configuration; otherwise, it returns false.
+     */
+    boolean canEnableNearbyInMixedModels();
+
     /**
      * @return new instance with the Nearby Selection settings properly configured
      */

core/src/main/java/ai/timefold/solver/core/config/heuristic/selector/move/composite/UnionMoveSelectorConfig.java

@@ -206,6 +206,11 @@ public boolean hasNearbySelectionConfig() {
                 && moveSelectorConfigList.stream().anyMatch(MoveSelectorConfig::hasNearbySelectionConfig);
     }
 
+    @Override
+    public boolean canEnableNearbyInMixedModels() {
+        return false;
+    }
+
     @Override
     public String toString() {
         return getClass().getSimpleName() + "(" + moveSelectorConfigList + ")";

core/src/main/java/ai/timefold/solver/core/config/heuristic/selector/move/generic/ChangeMoveSelectorConfig.java

@@ -104,6 +104,11 @@ public boolean hasNearbySelectionConfig() {
                 || (valueSelectorConfig != null && valueSelectorConfig.hasNearbySelectionConfig());
     }
 
+    @Override
+    public boolean canEnableNearbyInMixedModels() {
+        return false;
+    }
+
     @Override
     public String toString() {
         return getClass().getSimpleName() + "(" + entitySelectorConfig + ", " + valueSelectorConfig + ")";

core/src/main/java/ai/timefold/solver/core/config/heuristic/selector/move/generic/SwapMoveSelectorConfig.java

@@ -127,6 +127,11 @@ public boolean hasNearbySelectionConfig() {
                 || (secondaryEntitySelectorConfig != null && secondaryEntitySelectorConfig.hasNearbySelectionConfig());
     }
 
+    @Override
+    public boolean canEnableNearbyInMixedModels() {
+        return false;
+    }
+
     @Override
     public String toString() {
         return getClass().getSimpleName() + "(" + entitySelectorConfig

core/src/main/java/ai/timefold/solver/core/config/heuristic/selector/move/generic/chained/TailChainSwapMoveSelectorConfig.java

@@ -108,6 +108,11 @@ public boolean hasNearbySelectionConfig() {
                 || (valueSelectorConfig != null && valueSelectorConfig.hasNearbySelectionConfig());
     }
 
+    @Override
+    public boolean canEnableNearbyInMixedModels() {
+        return false;
+    }
+
     @Override
     public String toString() {
         return getClass().getSimpleName() + "(" + entitySelectorConfig + ", " + valueSelectorConfig + ")";

core/src/main/java/ai/timefold/solver/core/config/heuristic/selector/move/generic/list/ListChangeMoveSelectorConfig.java

@@ -106,6 +106,11 @@ public boolean hasNearbySelectionConfig() {
                 || (destinationSelectorConfig != null && destinationSelectorConfig.hasNearbySelectionConfig());
     }
 
+    @Override
+    public boolean canEnableNearbyInMixedModels() {
+        return true;
+    }
+
     @Override
     public String toString() {
         return getClass().getSimpleName() + "(" + valueSelectorConfig + ", " + destinationSelectorConfig + ")";

core/src/main/java/ai/timefold/solver/core/config/heuristic/selector/move/generic/list/ListSwapMoveSelectorConfig.java

@@ -104,6 +104,11 @@ public boolean hasNearbySelectionConfig() {
                 || (secondaryValueSelectorConfig != null && secondaryValueSelectorConfig.hasNearbySelectionConfig());
     }
 
+    @Override
+    public boolean canEnableNearbyInMixedModels() {
+        return true;
+    }
+
     @Override
     public String toString() {
         return getClass().getSimpleName() + "(" + valueSelectorConfig

core/src/main/java/ai/timefold/solver/core/config/heuristic/selector/move/generic/list/kopt/KOptListMoveSelectorConfig.java

@@ -138,6 +138,11 @@ public boolean hasNearbySelectionConfig() {
                 || (valueSelectorConfig != null && valueSelectorConfig.hasNearbySelectionConfig());
     }
 
+    @Override
+    public boolean canEnableNearbyInMixedModels() {
+        return true;
+    }
+
     @Override
     public String toString() {
         return getClass().getSimpleName() + "()";

core/src/main/java/ai/timefold/solver/core/impl/domain/solution/descriptor/SolutionDescriptor.java

@@ -166,10 +166,6 @@ public static <Solution_> SolutionDescriptor<Solution_> buildSolutionDescriptor(
             solutionDescriptor.constraintWeightSupplier.initialize(solutionDescriptor,
                     descriptorPolicy.getMemberAccessorFactory(), descriptorPolicy.getDomainAccessType());
         }
-        // Temporally disabling the mixed model
-        if (solutionDescriptor.hasBothBasicAndListVariables()) {
-            throw new IllegalStateException("Combining list variable and basic variables is currently not supported.");
-        }
         return solutionDescriptor;
     }
 

core/src/main/java/ai/timefold/solver/core/impl/heuristic/HeuristicConfigPolicy.java

@@ -161,6 +161,12 @@ public HeuristicConfigPolicy<Solution_> createPhaseConfigPolicy() {
         return cloneBuilder().build();
     }
 
+    public HeuristicConfigPolicy<Solution_> copyConfigPolicyWithoutNearbySetting() {
+        return cloneBuilder()
+                .withNearbyDistanceMeterClass(null)
+                .build();
+    }
+
     public HeuristicConfigPolicy<Solution_> createChildThreadConfigPolicy(ChildThreadType childThreadType) {
         return cloneBuilder()
                 .withLogIndentation(logIndentation + "        ")