1 files changed, 16 insertions, 0 deletions
diff --git a/packages/frontend/src/aiscript/common.ts b/packages/frontend/src/aiscript/common.ts
new file mode 100644
index 0000000000..ba5dfb8368
--- /dev/null
+++ b/packages/frontend/src/aiscript/common.ts
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { errors, utils } from '@syuilo/aiscript';
+import type { values } from '@syuilo/aiscript';
+
+export function assertStringAndIsIn<A extends readonly string[]>(value: values.Value | undefined, expects: A): asserts value is values.VStr & { value: A[number] } {
+	utils.assertString(value);
+	const str = value.value;
+	if (!expects.includes(str)) {
+		const expected = expects.map((expect) => `"${expect}"`).join(', ');
+		throw new errors.AiScriptRuntimeError(`"${value.value}" is not in ${expected}`);
+	}
+}