From 9d1baf07ec33d450bea8d87a61400898393fd7dc Mon Sep 17 00:00:00 2001
From: chensheng <csheng.dude@gmail.com>
Date: Mon, 16 Mar 2020 10:11:22 +0800
Subject: [PATCH] check invalid before names

---
 lib/Hook.js           |  3 +++
 lib/__tests__/Hook.js | 17 +++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/lib/Hook.js b/lib/Hook.js
index 55149f8..5eb6fa3 100644
--- a/lib/Hook.js
+++ b/lib/Hook.js
@@ -157,6 +157,9 @@ class Hook {
 					continue;
 				}
 				if (before.size > 0) {
+					if (i === 0) {
+						throw new Error(`Invalid before names [${[...before]}]`);
+					}
 					continue;
 				}
 			}
diff --git a/lib/__tests__/Hook.js b/lib/__tests__/Hook.js
index 71a73d5..0cb92d0 100644
--- a/lib/__tests__/Hook.js
+++ b/lib/__tests__/Hook.js
@@ -67,4 +67,21 @@ describe("Hook", () => {
 		hook.call();
 		expect(calls).toEqual(["E", "F", "C", "D", "B", "A"]);
 	});
+
+	it("should throw error when pass invalid before names", () => {
+		const hook = new SyncHook();
+
+		const calls = [];
+		hook.tap("A", () => calls.push("A"));
+
+		expect(() => {
+			hook.tap(
+				{
+					name: "B",
+					before: "C"
+				},
+				() => calls.push("B")
+			);
+		}).toThrowError("Invalid before names [C]");
+	});
 });