feat: hits when type a wrong sub commands

src/main/kotlin/command/MiraiTreeCommand.kt

@@ -1,6 +1,8 @@
 package com.github.asforest.mshell.command
 
-import com.github.asforest.mshell.command.resolver.PrefixedCommandSignature
+import com.github.asforest.mshell.command.mshell.MShellCommand
+import com.github.asforest.mshell.command.resolver.TreeCommand
+import com.github.asforest.mshell.util.MShellUtils.buildUsage
 import net.mamoe.mirai.console.command.*
 import net.mamoe.mirai.console.command.descriptor.*
 import net.mamoe.mirai.console.permission.Permission
@@ -25,18 +27,16 @@ abstract class MiraiTreeCommand (
     override val prefixOptional: Boolean = false,
 ) : Command {
 
-    abstract val subCommandFunctions: List<PrefixedCommandSignature>
+    abstract val subCommandFunctions: List<TreeCommand.PrefixedCommandSignature>
 
     override val usage: String by lazy {
         subCommandFunctions.joinToString("\n") { pfun ->
-            val label = pfun.prefix
+            val prefix = pfun.prefix
             val func = pfun.signature
 
             buildString {
                 append(CommandManager.commandPrefix)
-                append("$primaryName $label ")
-                append(func.parameters.joinToString(" ") { parameter -> parameter.identity})
-                append("    # ${func.description}")
+                append(buildUsage(MShellCommand.rootLabal + if (prefix.isNotEmpty()) " $prefix" else "", func))
             }
         }
     }

src/main/kotlin/command/mshell/MShellCommand.kt

@@ -3,10 +3,11 @@ package com.github.asforest.mshell.command.mshell
 import com.github.asforest.mshell.MShellPlugin
 import com.github.asforest.mshell.command.MiraiTreeCommand
 import com.github.asforest.mshell.command.resolver.AbstractArgumentParsers
+import com.github.asforest.mshell.command.resolver.CommandSignature
 import com.github.asforest.mshell.command.resolver.TreeCommand
-import com.github.asforest.mshell.command.resolver.PrefixedCommandSignature
 import com.github.asforest.mshell.permission.MShellPermissions
 import com.github.asforest.mshell.session.SessionUser
+import com.github.asforest.mshell.util.MShellUtils.buildUsage
 import com.github.asforest.mshell.util.MShellUtils.toSessionUser
 import net.mamoe.mirai.console.command.CommandSender
 import net.mamoe.mirai.console.permission.PermissionService.Companion.testPermission
@@ -21,12 +22,14 @@ object MShellCommand : MiraiTreeCommand(
     description = "MShell插件指令",
     permission = MShellPermissions.use
 ) {
+    val rootLabal = secondaryNames.first()
+
     const val Nobody = 0
     const val User = 1 shl 0
     const val Admin = 1 shl 1
     const val All = User or Admin
 
-    override val subCommandFunctions: List<PrefixedCommandSignature> by lazy {
+    override val subCommandFunctions: List<TreeCommand.PrefixedCommandSignature> by lazy {
         MainCommand.allCommands
     }
 
@@ -46,21 +49,27 @@ object MShellCommand : MiraiTreeCommand(
                     Nobody
             }
 
-            val afun = MainCommand.resolveCommandText(commandText.split(" "), senderPermission, "")
-            afun.callSuspend(CallContext(this, senderPermission))
+            val prefix = rootLabal
+            val arguments = commandText.split(" ").filter { it.isNotEmpty() }
 
+            if (arguments.isNotEmpty())
+            {
+                val afun = MainCommand.resolveCommandText(prefix, arguments, senderPermission)
+                afun.callSuspend(CallContext(this, senderPermission))
+            } else {
+                sendMessage("输入 /$prefix help 来查看帮助信息")
+            }
+        } catch (e: TreeCommand.MissingSubCommandException) {
+            sendMessage("可用的子指令：\n${e.availables.generateUsage(e.prefix)}")
         } catch (e: TreeCommand.NoFunctionMatchedException) {
-            if (commandText.isEmpty())
-                sendMessage("输入 /${secondaryNames.first()} help 来查看帮助信息")
-            else
-                sendMessage("未知指令。输入 /${secondaryNames.first()} help 来查看帮助信息")
+            sendMessage("未知子指令 ${e.label} 。可用的子指令：${e.availables.joinToString(", ") { it.name }}")
         } catch (e: TreeCommand.TooFewArgumentsException) {
-            val signature = listOf("/${secondaryNames.first()}", e.prefix, e.signature.name, e.signature.params)
+            val signature = listOf(e.prefix, e.signature.name, e.signature.params)
                 .filter { it.isNotEmpty() }
                 .joinToString(" ")
             sendMessage("参数太少。正确的参数列表：$signature")
         } catch (e: TreeCommand.TooManyArgumentsException) {
-            val signature = listOf("/${secondaryNames.first()}", e.prefix, e.signature.name, e.signature.params)
+            val signature = listOf(e.prefix, e.signature.name, e.signature.params)
                 .filter { it.isNotEmpty() }
                 .joinToString(" ")
             sendMessage("参数太多。正确的参数列表：$signature")
@@ -71,6 +80,18 @@ object MShellCommand : MiraiTreeCommand(
         }
     }
 
+    private fun List<CommandSignature>.generateUsage(prefix: String): String
+    {
+        return buildString {
+            for (funcation in this@generateUsage)
+            {
+                append("/")
+                append(buildUsage(prefix, funcation))
+                append("\n")
+            }
+        }.trim()
+    }
+
     data class CallContext(val sender: CommandSender, val permission: Int)
     {
         val isUser = permission and User

src/main/kotlin/command/mshell/MainCommand.kt

@@ -2,15 +2,16 @@ package com.github.asforest.mshell.command.mshell
 
 import com.github.asforest.mshell.MShellPlugin
 import com.github.asforest.mshell.command.mshell.MShellCommand.Admin
-import com.github.asforest.mshell.command.mshell.MShellCommand.User
 import com.github.asforest.mshell.command.mshell.MShellCommand.CallContext
+import com.github.asforest.mshell.command.mshell.MShellCommand.User
 import com.github.asforest.mshell.command.resolver.TreeCommand
 import com.github.asforest.mshell.configuration.MShellConfig
 import com.github.asforest.mshell.exception.business.*
 import com.github.asforest.mshell.model.Preset
 import com.github.asforest.mshell.permission.PresetGrants
 import com.github.asforest.mshell.session.Session
 import com.github.asforest.mshell.session.SessionManager
+import com.github.asforest.mshell.util.MShellUtils.buildUsage
 
 object MainCommand : TreeCommand()
 {
@@ -27,17 +28,16 @@ object MainCommand : TreeCommand()
     suspend fun CallContext.help()
     {
         sendMessage(buildString {
-            for ((label, func) in allCommands)
+            for ((prefix, func) in allCommands)
             {
                 if (func.permissionMask and permission == 0)
                     continue
 
-                append(listOf("/${MShellCommand.primaryName}", label, func.params).joinToString(" "))
-                if(func.description.isNotEmpty())
-                    append(": ${func.description}")
+                append("/")
+                append(buildUsage(MShellCommand.rootLabal + if (prefix.isNotEmpty()) " $prefix" else "", func))
                 append("\n")
             }
-        })
+        }.trim())
     }
 
     @Command(desc = "开启一个会话并将当前用户连接到这个会话", permission = Admin or User)

src/main/kotlin/command/resolver/CommandSignature.kt

@@ -1,11 +1,13 @@
 package com.github.asforest.mshell.command.resolver
 
 import kotlin.reflect.*
+import kotlin.reflect.full.extensionReceiverParameter
 import kotlin.reflect.full.isSubtypeOf
+import kotlin.reflect.full.valueParameters
 import kotlin.reflect.jvm.jvmErasure
 
 /**
- * @param name: 指令名字
+ * @param name: callable 标识符名字
  * @param callable: 指令KFunction对象
  * @param parameters: value parameter
  * @param extensionReceiverParameter: extension receiver parameter
@@ -20,8 +22,21 @@ data class CommandSignature(
     val permissionMask: Int,
     val description: String
 ) {
+    /**
+     * 字符串化后的parameters
+     */
     val params = parameters.joinToString(" ") { p -> p.identity }
 
+    companion object {
+        @JvmStatic
+        fun CreateFromKF(kf: KFunction<*>, prefix: String, permissionMask: Int, description: String): CommandSignature
+        {
+            val parameters = kf.valueParameters.map { Parameter(it.name ?: "", it.isOptional, it.isVararg, it.type) }
+
+            return CommandSignature(prefix, kf, parameters, kf.extensionReceiverParameter, permissionMask, description)
+        }
+    }
+
     data class Parameter(
         val name: String,
         val isOptional: Boolean,

src/main/kotlin/command/resolver/TreeCommand.kt

@@ -8,6 +8,14 @@ import kotlin.reflect.KVisibility
 import kotlin.reflect.full.*
 import kotlin.reflect.jvm.javaField
 
+/**
+ * 指令指令的抽象类（一些变量命名说明：
+ *
+ * labal：指命令字符串用空格分割后的第一个元素，比如ms auth add中的ms。用来匹配方法标识符
+ *
+ * arguments：指命令字符串用空格分割后从第二个开始的后面的所有元素，比如ms auth add 123中的auth add 123。用来匹配方法形参
+ *
+ */
 abstract class TreeCommand
 {
     /**
@@ -17,37 +25,25 @@ abstract class TreeCommand
         val functions = mutableListOf<PrefixedCommandSignature>()
 
         for (command in this.commands)
-        {
-            functions += PrefixedCommandSignature(command.prefix, command.signature)
-        }
+            functions += PrefixedCommandSignature("", command)
 
-        fun collectFromMemberProperty(parent: TreeCommand)
-        {
-            for (subCommand in parent.subCommandObjects.filter { !it.isAlias })
-                for (command in subCommand.subtree.commands)
-                    functions += PrefixedCommandSignature(subCommand.field + " " + command.prefix, command.signature)
-        }
-
-        collectFromMemberProperty(this)
+        for (subCommand in subCommandObjects.filter { !it.isAlias })
+            for (command in subCommand.subtree.commands)
+                functions += PrefixedCommandSignature(subCommand.field + " " + command.name, command)
 
         functions
     }
 
     /**
      * 所有定义在本类/子类里的指令函数列表
      */
-    protected val commands: List<PrefixedCommandSignature> by lazy {
+    protected val commands: List<CommandSignature> by lazy {
         this::class.functions
             .filter { it.isSubCommandFunction() }
             .onEach { it.checkModifiers() }
-            .map { func ->
-                val annotation = func.findAnnotation<Command>()!!
-
-                val signature = CommandSignature(func.name, func, func.valueParameters.map {
-                    CommandSignature.Parameter(it.name ?: "", it.isOptional, it.isVararg, it.type)
-                }, func.extensionReceiverParameter, annotation.permission, annotation.desc)
-
-                PrefixedCommandSignature(func.name, signature)
+            .map { funcation ->
+                val annotation = funcation.findAnnotation<Command>()!!
+                CommandSignature.CreateFromKF(funcation, funcation.name, annotation.permission, annotation.desc)
             }
     }
 
@@ -74,31 +70,32 @@ abstract class TreeCommand
 
     /**
      * 尝试解析Arguments
-     * @param commands 要被解析的Arguments字符串列表
-     * @param callerPermission 调用者拥有的权限，用来判断有无权限执行指令
      * @param prefix 指令前缀。用来知道当前函数是第几层子指令
+     * @param arguments 要被解析的Arguments字符串列表
+     * @param callerPermission 调用者拥有的权限，用来判断有无权限执行指令
      * @return 解析结果
+     * @throws MissingSubCommandException 没有任何实参被传进来
      * @throws NoFunctionMatchedException 没有对应的函数（解析失败）
      * @throws TooFewArgumentsException 实参太少
      * @throws TooManyArgumentsException 实参太多
      * @throws AbstractArgumentParsers.ArgumentParserException 解析成功，但参数类型不正确（不匹配）时
      * @throws PermissionDeniedException 解析成功，但权限不够时
      */
-    fun resolveCommandText(commands: List<String>, callerPermission: Int, prefix: String): ArgumentedFunction
+    fun resolveCommandText(prefix: String, arguments: List<String>, callerPermission: Int): ArgumentedFunction
     {
-        if(commands.isEmpty())
-            throw NoFunctionMatchedException()
+        if(arguments.isEmpty())
+            throw MissingSubCommandException(prefix, this.commands)
 
-        val label = commands[0]
-        val arguments = commands.drop(1)
+        val label = arguments[0]
+        val arguments = arguments.drop(1)
 
         val resolveResult = resolveWithinSelf(label, arguments)
 
         if (resolveResult == null)
         {
-            val subCommand = subCommandObjects.firstOrNull { it.field == label } ?: throw NoFunctionMatchedException()
+            val subCommand = subCommandObjects.firstOrNull { it.field == label } ?: throw NoFunctionMatchedException(prefix, label, this.commands)
             val pfx = prefix + (if(prefix.isNotEmpty()) " " else "") + subCommand.field
-            return subCommand.subtree.resolveCommandText(arguments, callerPermission, pfx)
+            return subCommand.subtree.resolveCommandText(pfx, arguments, callerPermission)
         }
 
         when(resolveResult)
@@ -118,9 +115,9 @@ abstract class TreeCommand
     {
         var tempResult: CommandCallResolver.ResolveResult? = null
 
-        for (function in this.commands.filter { it.prefix == label })
+        for (function in this.commands.filter { it.name == label })
         {
-            tempResult = CommandCallResolver.resolve(function.signature, arguments, this)
+            tempResult = CommandCallResolver.resolve(function, arguments, this)
 
             if (tempResult is CommandCallResolver.ResolveResult.ResolveCorrect)
                 return tempResult
@@ -140,14 +137,24 @@ abstract class TreeCommand
 
     class IllegalDeclarationException(message: String) : Exception(message)
 
-    class NoFunctionMatchedException : Exception()
+    class NoFunctionMatchedException(val prefix: String, val label: String, val availables: List<CommandSignature>) : Exception()
+
+    class MissingSubCommandException(val prefix: String, val availables: List<CommandSignature>) : Exception()
 
     class TooFewArgumentsException(val prefix: String, val signature: CommandSignature) : Exception()
 
     class TooManyArgumentsException(val prefix: String, val signature: CommandSignature) : Exception()
 
     class PermissionDeniedException(val prefix: String, val function: ArgumentedFunction) : Exception()
 
+    /**
+     * 带前缀版本的CommandSignature
+     */
+    data class PrefixedCommandSignature(
+        val prefix: String,
+        val signature: CommandSignature,
+    )
+
     /**
      * 代表一个定义在子对象里的指令函数列表
      */

src/main/kotlin/util/MShellUtils.kt

@@ -1,5 +1,6 @@
 package com.github.asforest.mshell.util
 
+import com.github.asforest.mshell.command.resolver.CommandSignature
 import com.github.asforest.mshell.session.SessionUser
 import net.mamoe.mirai.Bot
 import net.mamoe.mirai.console.command.CommandSender
@@ -61,4 +62,14 @@ object MShellUtils
 
         return SessionUser.FriendUser(user!!)
     }
+
+    fun buildUsage(prefix: String, function: CommandSignature, separator: String = ":"): String
+    {
+        return listOf(
+            prefix,
+            function.name,
+            function.params,
+        ).filter { it.isNotEmpty() }
+            .joinToString(" ") + if(function.description.isNotEmpty()) "$separator ${function.description}" else ""
+    }
 }