Unify the generic peirpheral system a litte

Allows registering arbitrary block lookup functions instead of a
platform-specific capability. This is roughly what Fabric did before,
but generalised to also take an invalidation callback.

This callback is a little nasty - it needs to be a NonNullableConsumer
on Forge, but that class isn't available on Fabric. For now, we make the
lookup function (and thus the generic peripheral provider) generic on
some <T extends Runnable> type, then specialise that on the Forge side.
Hopefully we can clean this up when NeoForge reworks capabilities.

projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/ComponentLookup.java

@@ -0,0 +1,36 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.peripheral.generic;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.state.BlockState;
+
+import javax.annotation.Nullable;
+
+/**
+ * Extract some component (for instance a capability on Forge, or a {@code BlockApiLookup} on Fabric) from a block and
+ * block entity.
+ *
+ * @param <C> A platform-specific type, used for the invalidation callback.
+ */
+public interface ComponentLookup<C extends Runnable> {
+    /**
+     * Extract some component from a block in the world.
+     *
+     * @param level       The current level.
+     * @param pos         The position of the block in the level.
+     * @param state       The block state at that position.
+     * @param blockEntity The block entity at that position.
+     * @param side        The side of the block to extract the component from. Implementations should try to use a
+     *                    sideless lookup first, but may fall back to a sided lookup if needed.
+     * @param invalidate  An invalidation function to call if this component changes.
+     * @return The found component, or {@code null} if not present.
+     */
+    @Nullable
+    Object find(Level level, BlockPos pos, BlockState state, BlockEntity blockEntity, Direction side, C invalidate);
+}

projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheralBuilder.java

@@ -6,12 +6,9 @@ package dan200.computercraft.shared.peripheral.generic;
 
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.peripheral.PeripheralType;
-import dan200.computercraft.core.methods.MethodSupplier;
 import dan200.computercraft.core.methods.NamedMethod;
 import dan200.computercraft.core.methods.PeripheralMethod;
-import dan200.computercraft.shared.computer.core.ServerContext;
 import net.minecraft.core.Direction;
-import net.minecraft.server.MinecraftServer;
 import net.minecraft.world.level.block.entity.BlockEntity;
 
 import javax.annotation.Nullable;
@@ -28,16 +25,10 @@ import java.util.Set;
  * See the platform-specific peripheral providers for the usage of this.
  */
 final class GenericPeripheralBuilder {
-    private final MethodSupplier<PeripheralMethod> peripheralMethods;
-
     private @Nullable String name;
     private final Set<String> additionalTypes = new HashSet<>(0);
     private final ArrayList<SaturatedMethod> methods = new ArrayList<>();
 
-    GenericPeripheralBuilder(MinecraftServer server) {
-        peripheralMethods = ServerContext.get(server).peripheralMethods();
-    }
-
     @Nullable
     IPeripheral toPeripheral(BlockEntity blockEntity, Direction side) {
         if (methods.isEmpty()) return null;
@@ -46,18 +37,16 @@ final class GenericPeripheralBuilder {
         return new GenericPeripheral(blockEntity, side, name, additionalTypes, methods);
     }
 
-    boolean addMethods(Object target) {
+    void addMethod(Object target, String name, PeripheralMethod method, @Nullable NamedMethod<PeripheralMethod> info) {
-        return peripheralMethods.forEachSelfMethod(target, (name, method, info) -> {
+        methods.add(new SaturatedMethod(target, name, method));
-            methods.add(new SaturatedMethod(target, name, method));
 
-            // If we have a peripheral type, use it. Always pick the smallest one, so it's consistent (assuming mods
+        // If we have a peripheral type, use it. Always pick the smallest one, so it's consistent (assuming mods
-            // don't change).
+        // don't change).
-            var type = info == null ? null : info.genericType();
+        var type = info == null ? null : info.genericType();
-            if (type != null && type.getPrimaryType() != null) {
+        if (type != null && type.getPrimaryType() != null) {
-                var primaryType = type.getPrimaryType();
+            var primaryType = type.getPrimaryType();
-                if (this.name == null || this.name.compareTo(primaryType) > 0) this.name = primaryType;
+            if (this.name == null || this.name.compareTo(primaryType) > 0) this.name = primaryType;
-            }
+        }
-            if (type != null) additionalTypes.addAll(type.getAdditionalTypes());
+        if (type != null) additionalTypes.addAll(type.getAdditionalTypes());
-        });
     }
 }

projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheralProvider.java

@@ -0,0 +1,69 @@
+// SPDX-FileCopyrightText: 2020 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.peripheral.generic;
+
+import dan200.computercraft.api.lua.GenericSource;
+import dan200.computercraft.api.peripheral.IPeripheral;
+import dan200.computercraft.core.methods.MethodSupplier;
+import dan200.computercraft.core.methods.PeripheralMethod;
+import dan200.computercraft.shared.computer.core.ServerContext;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.annotation.Nullable;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A peripheral provider which finds methods from various {@linkplain GenericSource generic sources}.
+ * <p>
+ * Methods are found using the original block entity itself and a registered list of {@link ComponentLookup}s.
+ *
+ * @param <C> A platform-specific type, used for the invalidation callback.
+ */
+public final class GenericPeripheralProvider<C extends Runnable> {
+    private static final Logger LOG = LoggerFactory.getLogger(GenericPeripheralProvider.class);
+
+    private final List<ComponentLookup<? super C>> lookups = new ArrayList<>();
+
+    /**
+     * Register a component lookup function.
+     *
+     * @param lookup The component lookup function.
+     */
+    public synchronized void registerLookup(ComponentLookup<? super C> lookup) {
+        Objects.requireNonNull(lookup);
+        if (!lookups.contains(lookup)) lookups.add(lookup);
+    }
+
+    public void forEachMethod(MethodSupplier<PeripheralMethod> methods, Level level, BlockPos pos, Direction side, BlockEntity blockEntity, C invalidate, MethodSupplier.TargetedConsumer<PeripheralMethod> consumer) {
+        methods.forEachMethod(blockEntity, consumer);
+
+        for (var lookup : lookups) {
+            var contents = lookup.find(level, pos, blockEntity.getBlockState(), blockEntity, side, invalidate);
+            if (contents != null) methods.forEachMethod(contents, consumer);
+        }
+    }
+
+    @Nullable
+    public IPeripheral getPeripheral(Level level, BlockPos pos, Direction side, @Nullable BlockEntity blockEntity, C invalidate) {
+        if (blockEntity == null) return null;
+
+        var server = level.getServer();
+        if (server == null) {
+            LOG.warn("Fetching peripherals on a non-server level {}.", level, new IllegalStateException("Fetching peripherals on a non-server level."));
+            return null;
+        }
+
+        var builder = new GenericPeripheralBuilder();
+        forEachMethod(ServerContext.get(server).peripheralMethods(), level, pos, side, blockEntity, invalidate, builder::addMethod);
+        return builder.toPeripheral(blockEntity, side);
+    }
+}

projects/fabric/src/main/java/dan200/computercraft/impl/Peripherals.java

@@ -0,0 +1,35 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.impl;
+
+import dan200.computercraft.api.peripheral.IPeripheral;
+import dan200.computercraft.shared.peripheral.generic.ComponentLookup;
+import dan200.computercraft.shared.peripheral.generic.GenericPeripheralProvider;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.entity.BlockEntity;
+
+import javax.annotation.Nullable;
+
+/**
+ * The registry for peripheral providers.
+ * <p>
+ * This lives in the {@code impl} package despite it not being part of the public API, in order to mirror Forge's class.
+ */
+public final class Peripherals {
+    private static final GenericPeripheralProvider<Runnable> genericProvider = new GenericPeripheralProvider<>();
+
+    private Peripherals() {
+    }
+
+    public static void addGenericLookup(ComponentLookup<? super Runnable> lookup) {
+        genericProvider.registerLookup(lookup);
+    }
+
+    public static @Nullable IPeripheral getGenericPeripheral(Level level, BlockPos pos, Direction side, @Nullable BlockEntity blockEntity, Runnable invalidate) {
+        return genericProvider.getPeripheral(level, pos, side, blockEntity, invalidate);
+    }
+}

projects/fabric/src/main/java/dan200/computercraft/shared/ComputerCraft.java

@@ -8,6 +8,7 @@ import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.detail.FabricDetailRegistries;
 import dan200.computercraft.api.node.wired.WiredElementLookup;
 import dan200.computercraft.api.peripheral.PeripheralLookup;
+import dan200.computercraft.impl.Peripherals;
 import dan200.computercraft.shared.command.CommandComputerCraft;
 import dan200.computercraft.shared.config.Config;
 import dan200.computercraft.shared.config.ConfigSpec;
@@ -100,6 +101,8 @@ public class ComputerCraft {
         FabricDetailRegistries.FLUID_VARIANT.addProvider(FluidDetails::fill);
 
         ComputerCraftAPI.registerGenericSource(new InventoryMethods());
+
+        Peripherals.addGenericLookup((world, pos, state, blockEntity, side, invalidate) -> InventoryMethods.extractContainer(world, pos, state, blockEntity, side));
     }
 
     private record ReloadListener(String name, PreparableReloadListener listener)

projects/fabric/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheralProvider.java

@@ -1,52 +0,0 @@
-// SPDX-FileCopyrightText: 2020 The CC: Tweaked Developers
-//
-// SPDX-License-Identifier: MPL-2.0
-
-package dan200.computercraft.shared.peripheral.generic;
-
-import dan200.computercraft.api.peripheral.IPeripheral;
-import dan200.computercraft.shared.peripheral.generic.methods.InventoryMethods;
-import net.minecraft.core.BlockPos;
-import net.minecraft.core.Direction;
-import net.minecraft.world.level.Level;
-import net.minecraft.world.level.block.entity.BlockEntity;
-import net.minecraft.world.level.block.state.BlockState;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import javax.annotation.Nullable;
-import java.util.List;
-
-public class GenericPeripheralProvider {
-    private static final Logger LOG = LoggerFactory.getLogger(GenericPeripheralProvider.class);
-
-    interface Lookup<T> {
-        @Nullable
-        T find(Level world, BlockPos pos, BlockState state, @Nullable BlockEntity blockEntity, Direction context);
-    }
-
-    private static final List<Lookup<?>> lookups = List.of(
-        InventoryMethods::extractContainer
-    );
-
-    @Nullable
-    public static IPeripheral getPeripheral(Level level, BlockPos pos, Direction side, @Nullable BlockEntity blockEntity) {
-        if (blockEntity == null) return null;
-
-        var server = level.getServer();
-        if (server == null) {
-            LOG.warn("Fetching peripherals on a non-server level {}.", level, new IllegalStateException("Fetching peripherals on a non-server level."));
-            return null;
-        }
-
-        var builder = new GenericPeripheralBuilder(server);
-        builder.addMethods(blockEntity);
-
-        for (var lookup : lookups) {
-            var contents = lookup.find(level, pos, blockEntity.getBlockState(), blockEntity, side);
-            if (contents != null) builder.addMethods(contents);
-        }
-
-        return builder.toPeripheral(blockEntity, side);
-    }
-}

projects/fabric/src/main/java/dan200/computercraft/shared/platform/PlatformHelperImpl.java

@@ -14,12 +14,12 @@ import dan200.computercraft.api.network.wired.WiredElement;
 import dan200.computercraft.api.node.wired.WiredElementLookup;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.peripheral.PeripheralLookup;
+import dan200.computercraft.impl.Peripherals;
 import dan200.computercraft.mixin.ArgumentTypeInfosAccessor;
 import dan200.computercraft.shared.config.ConfigFile;
 import dan200.computercraft.shared.network.NetworkMessage;
 import dan200.computercraft.shared.network.client.ClientNetworkContext;
 import dan200.computercraft.shared.network.container.ContainerData;
-import dan200.computercraft.shared.peripheral.generic.GenericPeripheralProvider;
 import dan200.computercraft.shared.util.InventoryUtil;
 import net.fabricmc.fabric.api.event.player.AttackEntityCallback;
 import net.fabricmc.fabric.api.event.player.UseBlockCallback;
@@ -202,7 +202,7 @@ public class PlatformHelperImpl implements PlatformHelper {
 
     @Override
     public ComponentAccess<IPeripheral> createPeripheralAccess(Consumer<Direction> invalidate) {
-        return new PeripheralAccessImpl();
+        return new PeripheralAccessImpl(invalidate);
     }
 
     @Override
@@ -476,8 +476,11 @@ public class PlatformHelperImpl implements PlatformHelper {
     }
 
     private static final class PeripheralAccessImpl extends ComponentAccessImpl<IPeripheral> {
-        private PeripheralAccessImpl() {
+        private final Runnable[] invalidators = new Runnable[6];
+
+        private PeripheralAccessImpl(Consumer<Direction> invalidate) {
             super(PeripheralLookup.get());
+            for (var dir : Direction.values()) invalidators[dir.ordinal()] = () -> invalidate.accept(dir);
         }
 
         @Nullable
@@ -487,7 +490,8 @@ public class PlatformHelperImpl implements PlatformHelper {
             if (result != null) return result;
 
             var cache = caches[direction.ordinal()];
-            return GenericPeripheralProvider.getPeripheral(level, cache.getPos(), direction.getOpposite(), cache.getBlockEntity());
+            var invalidate = invalidators[direction.ordinal()];
+            return Peripherals.getGenericPeripheral(level, cache.getPos(), direction.getOpposite(), cache.getBlockEntity(), invalidate);
         }
     }
 }

projects/forge/src/main/java/dan200/computercraft/impl/ComputerCraftAPIImpl.java

@@ -11,7 +11,6 @@ import dan200.computercraft.api.network.wired.WiredElement;
 import dan200.computercraft.api.peripheral.IPeripheralProvider;
 import dan200.computercraft.impl.detail.DetailRegistryImpl;
 import dan200.computercraft.shared.details.FluidData;
-import dan200.computercraft.shared.peripheral.generic.GenericPeripheralProvider;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.world.level.BlockGetter;
@@ -45,7 +44,7 @@ public final class ComputerCraftAPIImpl extends AbstractComputerCraftAPI impleme
 
     @Override
     public void registerGenericCapability(Capability<?> capability) {
-        GenericPeripheralProvider.addCapability(capability);
+        Peripherals.registerGenericCapability(capability);
     }
 
     @Override

projects/forge/src/main/java/dan200/computercraft/impl/Peripherals.java

@@ -6,12 +6,16 @@ package dan200.computercraft.impl;
 
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.peripheral.IPeripheralProvider;
+import dan200.computercraft.shared.peripheral.generic.ComponentLookup;
 import dan200.computercraft.shared.peripheral.generic.GenericPeripheralProvider;
+import dan200.computercraft.shared.platform.InvalidateCallback;
 import dan200.computercraft.shared.util.CapabilityUtil;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.world.level.Level;
-import net.minecraftforge.common.util.NonNullConsumer;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.state.BlockState;
+import net.minecraftforge.common.capabilities.Capability;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -22,10 +26,16 @@ import java.util.Objects;
 
 import static dan200.computercraft.shared.Capabilities.CAPABILITY_PERIPHERAL;
 
+/**
+ * The registry for peripheral providers.
+ * <p>
+ * This lives in the {@code impl} package despite it not being part of the public API, in order to mirror Forge's class.
+ */
 public final class Peripherals {
     private static final Logger LOG = LoggerFactory.getLogger(Peripherals.class);
 
     private static final Collection<IPeripheralProvider> providers = new LinkedHashSet<>();
+    private static final GenericPeripheralProvider<InvalidateCallback> genericProvider = new GenericPeripheralProvider<>();
 
     private Peripherals() {
     }
@@ -35,13 +45,39 @@ public final class Peripherals {
         providers.add(provider);
     }
 
+    public static void registerGenericLookup(ComponentLookup<InvalidateCallback> lookup) {
+        genericProvider.registerLookup(lookup);
+    }
+
+    /**
+     * A {@link ComponentLookup} for {@linkplain Capability capabilities}.
+     * <p>
+     * This is a record to ensure that adding the same capability multiple times only results in one lookup being
+     * present in the resulting list.
+     *
+     * @param capability The capability to lookup
+     * @param <T>        The type of the capability we look up.
+     */
+    private record CapabilityLookup<T>(Capability<T> capability) implements ComponentLookup<InvalidateCallback> {
+        @Nullable
+        @Override
+        public T find(Level level, BlockPos pos, BlockState state, BlockEntity blockEntity, Direction side, InvalidateCallback invalidate) {
+            return CapabilityUtil.unwrap(CapabilityUtil.getCapability(blockEntity, this.capability(), side), invalidate);
+        }
+    }
+
+    public static void registerGenericCapability(Capability<?> capability) {
+        Objects.requireNonNull(capability, "Capability cannot be null");
+        registerGenericLookup(new CapabilityLookup<>(capability));
+    }
+
     @Nullable
-    public static IPeripheral getPeripheral(Level world, BlockPos pos, Direction side, NonNullConsumer<Object> invalidate) {
+    public static IPeripheral getPeripheral(Level world, BlockPos pos, Direction side, InvalidateCallback invalidate) {
         return world.isInWorldBounds(pos) && !world.isClientSide ? getPeripheralAt(world, pos, side, invalidate) : null;
     }
 
     @Nullable
-    private static IPeripheral getPeripheralAt(Level world, BlockPos pos, Direction side, NonNullConsumer<? super Object> invalidate) {
+    private static IPeripheral getPeripheralAt(Level world, BlockPos pos, Direction side, InvalidateCallback invalidate) {
         var block = world.getBlockEntity(pos);
         if (block != null) {
             var peripheral = block.getCapability(CAPABILITY_PERIPHERAL, side);
@@ -58,7 +94,6 @@ public final class Peripherals {
             }
         }
 
-        return GenericPeripheralProvider.getPeripheral(world, pos, side, invalidate);
+        return genericProvider.getPeripheral(world, pos, side, block, invalidate);
     }
-
 }

projects/forge/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheralProvider.java

@@ -1,54 +0,0 @@
-// SPDX-FileCopyrightText: 2020 The CC: Tweaked Developers
-//
-// SPDX-License-Identifier: MPL-2.0
-
-package dan200.computercraft.shared.peripheral.generic;
-
-import dan200.computercraft.api.peripheral.IPeripheral;
-import dan200.computercraft.shared.util.CapabilityUtil;
-import net.minecraft.core.BlockPos;
-import net.minecraft.core.Direction;
-import net.minecraft.world.level.Level;
-import net.minecraftforge.common.capabilities.Capability;
-import net.minecraftforge.common.util.NonNullConsumer;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import javax.annotation.Nullable;
-import java.util.ArrayList;
-import java.util.Objects;
-
-public class GenericPeripheralProvider {
-    private static final Logger LOG = LoggerFactory.getLogger(GenericPeripheralProvider.class);
-
-    private static final ArrayList<Capability<?>> capabilities = new ArrayList<>();
-
-    public static synchronized void addCapability(Capability<?> capability) {
-        Objects.requireNonNull(capability, "Capability cannot be null");
-        if (!capabilities.contains(capability)) capabilities.add(capability);
-    }
-
-    @Nullable
-    public static IPeripheral getPeripheral(Level level, BlockPos pos, Direction side, NonNullConsumer<Object> invalidate) {
-        var blockEntity = level.getBlockEntity(pos);
-        if (blockEntity == null) return null;
-
-        var server = level.getServer();
-        if (server == null) {
-            LOG.warn("Fetching peripherals on a non-server level {}.", level, new IllegalStateException("Fetching peripherals on a non-server level."));
-            return null;
-        }
-
-        var builder = new GenericPeripheralBuilder(server);
-        builder.addMethods(blockEntity);
-
-        for (var capability : capabilities) {
-            var wrapper = CapabilityUtil.getCapability(blockEntity, capability, side);
-            wrapper.ifPresent(contents -> {
-                if (builder.addMethods(contents)) CapabilityUtil.addListener(wrapper, invalidate);
-            });
-        }
-
-        return builder.toPeripheral(blockEntity, side);
-    }
-}

projects/forge/src/main/java/dan200/computercraft/shared/platform/InvalidateCallback.java

@@ -0,0 +1,33 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.platform;
+
+import dan200.computercraft.shared.peripheral.generic.ComponentLookup;
+import net.minecraftforge.common.util.LazyOptional;
+import net.minecraftforge.common.util.NonNullConsumer;
+
+/**
+ * A function which may be called when a capability (or some other object) has been invalidated.
+ * <p>
+ * This extends {@link NonNullConsumer} for use with {@link LazyOptional#addListener(NonNullConsumer)}, and
+ * {@link Runnable} for use with {@link ComponentLookup}.
+ */
+public interface InvalidateCallback extends Runnable, NonNullConsumer<Object> {
+    @Override
+    default void accept(Object o) {
+        run();
+    }
+
+    /**
+     * Cast this callback to a {@link NonNullConsumer} of an arbitrary type.
+     *
+     * @param <T> The type of the consumer, normally a {@link LazyOptional}.
+     * @return {@code this}, but with a compatible type.
+     */
+    @SuppressWarnings("unchecked")
+    default <T> NonNullConsumer<T> castConsumer() {
+        return (NonNullConsumer<T>) this;
+    }
+}

projects/forge/src/main/java/dan200/computercraft/shared/platform/PlatformHelperImpl.java

@@ -63,7 +63,6 @@ import net.minecraftforge.common.crafting.CraftingHelper;
 import net.minecraftforge.common.crafting.conditions.ICondition;
 import net.minecraftforge.common.crafting.conditions.ModLoadedCondition;
 import net.minecraftforge.common.extensions.IForgeMenuType;
-import net.minecraftforge.common.util.NonNullConsumer;
 import net.minecraftforge.event.ForgeEventFactory;
 import net.minecraftforge.eventbus.api.Event;
 import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
@@ -429,20 +428,19 @@ public class PlatformHelperImpl implements PlatformHelper {
     }
 
     private abstract static class ComponentAccessImpl<T> implements ComponentAccess<T> {
-        private final NonNullConsumer<Object>[] invalidators;
+        private final InvalidateCallback[] invalidators;
         private @Nullable Level level;
         private @Nullable BlockPos pos;
 
         ComponentAccessImpl(Consumer<Direction> invalidate) {
             // Generate a cache of invalidation functions so we can guarantee we only ever have one registered per
             // capability - there's no way to remove these callbacks!
-            @SuppressWarnings({ "unchecked", "rawtypes" })
+            var invalidators = this.invalidators = new InvalidateCallback[6];
-            var invalidators = this.invalidators = new NonNullConsumer[6];
+            for (var dir : Direction.values()) invalidators[dir.ordinal()] = () -> invalidate.accept(dir);
-            for (var dir : Direction.values()) invalidators[dir.ordinal()] = x -> invalidate.accept(dir);
         }
 
         @Nullable
-        protected abstract T get(ServerLevel world, BlockPos pos, Direction side, NonNullConsumer<Object> invalidate);
+        protected abstract T get(ServerLevel world, BlockPos pos, Direction side, InvalidateCallback invalidate);
 
         @Nullable
         @Override
@@ -463,7 +461,7 @@ public class PlatformHelperImpl implements PlatformHelper {
 
         @Nullable
         @Override
-        protected IPeripheral get(ServerLevel world, BlockPos pos, Direction side, NonNullConsumer<Object> invalidate) {
+        protected IPeripheral get(ServerLevel world, BlockPos pos, Direction side, InvalidateCallback invalidate) {
             return Peripherals.getPeripheral(world, pos, side, invalidate);
         }
     }
@@ -478,7 +476,7 @@ public class PlatformHelperImpl implements PlatformHelper {
 
         @Nullable
         @Override
-        protected T get(ServerLevel world, BlockPos pos, Direction side, NonNullConsumer<Object> invalidate) {
+        protected T get(ServerLevel world, BlockPos pos, Direction side, InvalidateCallback invalidate) {
             if (!world.isLoaded(pos)) return null;
 
             var blockEntity = world.getBlockEntity(pos);

projects/forge/src/main/java/dan200/computercraft/shared/util/CapabilityUtil.java

@@ -4,11 +4,11 @@
 
 package dan200.computercraft.shared.util;
 
+import dan200.computercraft.shared.platform.InvalidateCallback;
 import net.minecraft.core.Direction;
 import net.minecraftforge.common.capabilities.Capability;
 import net.minecraftforge.common.capabilities.ICapabilityProvider;
 import net.minecraftforge.common.util.LazyOptional;
-import net.minecraftforge.common.util.NonNullConsumer;
 
 import javax.annotation.Nullable;
 
@@ -32,18 +32,11 @@ public final class CapabilityUtil {
         }
     }
 
-    public static <T> void addListener(LazyOptional<T> p, NonNullConsumer<? super LazyOptional<T>> invalidate) {
-        // We can make this safe with invalidate::accept, but then we're allocating it's just kind of absurd.
-        @SuppressWarnings("unchecked")
-        var safeInvalidate = (NonNullConsumer<LazyOptional<T>>) invalidate;
-        p.addListener(safeInvalidate);
-    }
-
     @Nullable
-    public static <T> T unwrap(LazyOptional<T> p, NonNullConsumer<? super LazyOptional<T>> invalidate) {
+    public static <T> T unwrap(LazyOptional<T> p, InvalidateCallback invalidate) {
         if (!p.isPresent()) return null;
 
-        addListener(p, invalidate);
+        p.addListener(invalidate.castConsumer());
         return p.orElseThrow(NullPointerException::new);
     }