Change CommandCallResolverProvider to SingletonExtension

backend/mirai-console/src/command/resolve/BuiltInCommandCallResolver.kt

@@ -17,8 +17,6 @@ import net.mamoe.mirai.console.command.descriptor.ArgumentAcceptance.Companion.i
 import net.mamoe.mirai.console.command.parse.CommandCall
 import net.mamoe.mirai.console.command.parse.CommandValueArgument
 import net.mamoe.mirai.console.command.parse.DefaultCommandValueArgument
-import net.mamoe.mirai.console.extensions.CommandCallResolverProvider
-import net.mamoe.mirai.console.extensions.CommandCallResolverProviderImpl
 import net.mamoe.mirai.console.internal.data.classifierAsKClass
 import net.mamoe.mirai.console.util.ConsoleExperimentalApi
 import net.mamoe.mirai.console.util.safeCast
@@ -31,21 +29,20 @@ import net.mamoe.mirai.message.data.asMessageChain
 @ConsoleExperimentalApi
 @ExperimentalCommandDescriptors
 public object BuiltInCommandCallResolver : CommandCallResolver {
-    public object Provider : CommandCallResolverProvider by CommandCallResolverProviderImpl(BuiltInCommandCallResolver)
+    override fun resolve(call: CommandCall): CommandResolveResult {
-
+        val callee = CommandManager.matchCommand(call.calleeName) ?: return CommandResolveResult(null)
-    override fun resolve(call: CommandCall): ResolvedCommandCall? {
-        val callee = CommandManager.matchCommand(call.calleeName) ?: return null
 
         val valueArguments = call.valueArguments
         val context = callee.safeCast<CommandArgumentContextAware>()?.context
 
-        val signature = resolveImpl(call.caller, callee, valueArguments, context) ?: return null
+        val signature = resolveImpl(call.caller, callee, valueArguments, context) ?: return CommandResolveResult(null)
 
-        return ResolvedCommandCallImpl(call.caller,
+        return CommandResolveResult(ResolvedCommandCallImpl(call.caller,
             callee,
             signature.signature,
             signature.zippedArguments.map { it.second },
             context ?: EmptyCommandArgumentContext)
+        )
     }
 
     private data class ResolveData(

backend/mirai-console/src/command/resolve/CommandCallResolver.kt

@@ -9,11 +9,45 @@
 
 package net.mamoe.mirai.console.command.resolve
 
+import net.mamoe.mirai.console.command.CommandExecuteResult
 import net.mamoe.mirai.console.command.descriptor.ExperimentalCommandDescriptors
 import net.mamoe.mirai.console.command.parse.CommandCall
 import net.mamoe.mirai.console.extensions.CommandCallResolverProvider
 import net.mamoe.mirai.console.internal.extension.GlobalComponentStorage
 import net.mamoe.mirai.console.util.ConsoleExperimentalApi
+import net.mamoe.mirai.console.util.safeCast
+import org.jetbrains.annotations.Contract
+import kotlin.contracts.InvocationKind
+import kotlin.contracts.contract
+
+@ExperimentalCommandDescriptors
+public class CommandResolveResult private constructor(
+    internal val value: Any?,
+) {
+    @get:Contract(pure = true)
+    public val call: ResolvedCommandCall?
+        get() = value.safeCast()
+
+    @get:Contract(pure = true)
+    public val failure: CommandExecuteResult.Failure?
+        get() = value.safeCast()
+
+    public inline fun <R> fold(
+        onSuccess: (ResolvedCommandCall) -> R,
+        onFailure: (CommandExecuteResult.Failure) -> R,
+    ): R {
+        contract {
+            callsInPlace(onSuccess, InvocationKind.AT_MOST_ONCE)
+            callsInPlace(onFailure, InvocationKind.AT_MOST_ONCE)
+        }
+        call?.let(onSuccess)
+        failure?.let(onFailure)
+        null!!
+    }
+
+    public constructor(call: ResolvedCommandCall?) : this(call as Any?)
+    public constructor(failure: CommandExecuteResult.Failure) : this(failure as Any)
+}
 
 /**
  * The resolver converting a [CommandCall] into [ResolvedCommandCall] based on registered []
@@ -23,19 +57,17 @@ import net.mamoe.mirai.console.util.ConsoleExperimentalApi
  */
 @ExperimentalCommandDescriptors
 public interface CommandCallResolver {
-    public fun resolve(call: CommandCall): ResolvedCommandCall?
+    public fun resolve(call: CommandCall): CommandResolveResult
 
     public companion object {
         @JvmName("resolveCall")
         @ConsoleExperimentalApi
         @ExperimentalCommandDescriptors
-        public fun CommandCall.resolve(): ResolvedCommandCall? {
+        public fun CommandCall.resolve(): CommandResolveResult {
             GlobalComponentStorage.run {
-                CommandCallResolverProvider.useExtensions { provider ->
+                val instance = CommandCallResolverProvider.findSingletonInstance(CommandCallResolverProvider.builtinImplementation)
-                    provider.instance.resolve(this@resolve)?.let { return it }
+                return instance.resolve(this@resolve)
-                }
             }
-            return null
         }
     }
 }

backend/mirai-console/src/extensions/CommandCallResolverProvider.kt

@@ -12,14 +12,13 @@ package net.mamoe.mirai.console.extensions
 import net.mamoe.mirai.console.command.descriptor.ExperimentalCommandDescriptors
 import net.mamoe.mirai.console.command.resolve.BuiltInCommandCallResolver
 import net.mamoe.mirai.console.command.resolve.CommandCallResolver
-import net.mamoe.mirai.console.extension.AbstractInstanceExtensionPoint
+import net.mamoe.mirai.console.extension.AbstractSingletonExtensionPoint
-import net.mamoe.mirai.console.extension.InstanceExtension
+import net.mamoe.mirai.console.extension.SingletonExtension
 
 @ExperimentalCommandDescriptors
-public interface CommandCallResolverProvider : InstanceExtension<CommandCallResolver> {
+public interface CommandCallResolverProvider : SingletonExtension<CommandCallResolver> {
     public companion object ExtensionPoint :
-        AbstractInstanceExtensionPoint<CommandCallResolverProvider, CommandCallResolver>(CommandCallResolverProvider::class,
+        AbstractSingletonExtensionPoint<CommandCallResolverProvider, CommandCallResolver>(CommandCallResolverProvider::class, BuiltInCommandCallResolver)
-            BuiltInCommandCallResolver.Provider)
 }
 
 @ExperimentalCommandDescriptors