judge: check checker path

packages/hydrojudge/locales/zh.yaml

@@ -36,4 +36,5 @@ Unknown checker type {0}.: 未知的比较器类型 {0}。
 Unknown language type.: 未知的语言类型。
 Unsupported language {0}.: 不支持的语言 {0}。
 User output longer than standard answer.: 选手输出比标准输出长。
+You did not specify a checker.: 你没有指定比较器文件。
 Your program returned {0}.: 您的程序返回了{0}。

packages/hydrojudge/package.json

@@ -1,7 +1,7 @@
 {
     "name": "@hydrooj/hydrojudge",
     "bin": "bin/hydrojudge.js",
-    "version": "2.13.1",
+    "version": "2.13.2",
     "main": "package.json",
     "author": "undefined <i@undefined.moe>",
     "repository": "https://github.com/hydro-dev/Hydro.git",

packages/hydrojudge/src/cases.ts

@@ -195,6 +195,9 @@ function isValidConfig(config) {
     }
     const memMax = max(config.subtasks.map((subtask) => subtask.memory));
     if (memMax > parseMemoryMB(getConfig('memoryMax'))) throw new FormatError('Memory limit larger than memory_max');
+    if (['default', 'strict'].includes(config.checker_type || 'default') && !config.checker) {
+        throw new FormatError('You did not specify a checker.');
+    }
 }
 
 export default async function readCases(folder: string, cfg: Record<string, any> = {}, args) {