From 1b2ea3c6bf64650d94fa93da23f22887d7742d2a Mon Sep 17 00:00:00 2001
From: jackb-p <jackbondpreston@outlook.com>
Date: Thu, 4 Aug 2016 18:16:09 +0100
Subject: [PATCH] Add runtime error checking for custom JS

---
 TriviaBot/bot/APIHelper.cpp        |  4 ++++
 TriviaBot/bot/js/CommandHelper.cpp |  2 +-
 TriviaBot/bot/js/V8Instance.cpp    | 29 ++++++++++++++++++++++-------
 3 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/TriviaBot/bot/APIHelper.cpp b/TriviaBot/bot/APIHelper.cpp
index 2e8fd03..5df8e88 100644
--- a/TriviaBot/bot/APIHelper.cpp
+++ b/TriviaBot/bot/APIHelper.cpp
@@ -15,6 +15,10 @@ APIHelper::APIHelper() : BASE_URL("https://discordapp.com/api"), CHANNELS_URL(BA
 }
 
 void APIHelper::send_message(std::string channel_id, std::string message) {
+	if (message == "") {
+		Logger::write("[send_message] Tried to send empty message", Logger::LogLevel::Warning);
+	}
+
 	const std::string url = CHANNELS_URL + "/" + channel_id + "/messages";
 	json data = {
 		{ "content", message }
diff --git a/TriviaBot/bot/js/CommandHelper.cpp b/TriviaBot/bot/js/CommandHelper.cpp
index d641f8b..4722632 100644
--- a/TriviaBot/bot/js/CommandHelper.cpp
+++ b/TriviaBot/bot/js/CommandHelper.cpp
@@ -34,7 +34,7 @@ CommandHelper::CommandHelper() {
 		}
 	}
 
-	Logger::write(std::to_string(commands.size()) + " custom command loaded", Logger::LogLevel::Info);
+	Logger::write(std::to_string(commands.size()) + " custom command(s) loaded", Logger::LogLevel::Info);
 
 	sqlite3_finalize(stmt);
 	sqlite3_close(db);
diff --git a/TriviaBot/bot/js/V8Instance.cpp b/TriviaBot/bot/js/V8Instance.cpp
index a8fd3f0..78ba8cf 100644
--- a/TriviaBot/bot/js/V8Instance.cpp
+++ b/TriviaBot/bot/js/V8Instance.cpp
@@ -67,22 +67,37 @@ void V8Instance::exec_js(std::string js, std::string channel_id) {
 	// compile
 	Logger::write("[v8] Isolate nullptr? " + std::to_string(isolate == nullptr) + " Context empty? " + std::to_string(context.IsEmpty()), Logger::LogLevel::Debug);
 
-	TryCatch try_catch(isolate);
+	TryCatch compile_try_catch(isolate);
 	Local<Script> script;
 
 	if (!Script::Compile(context, source).ToLocal(&script)) {
-		String::Utf8Value error(try_catch.Exception());
-		Logger::write("[v8] Compilation error: " + std::string((const char *) *error), Logger::LogLevel::Debug);
+		String::Utf8Value error(compile_try_catch.Exception());
+
+		std::string err_msg = *error;
+		Logger::write("[v8] Compilation error: " + err_msg, Logger::LogLevel::Debug);
+		ah->send_message(channel_id, ":warning: **Compilation error:** `" + err_msg + "`");
+
+		return;
+	}
+
+	TryCatch run_try_catch(isolate);
+	MaybeLocal<Value> v = script->Run(context);
+	if (v.IsEmpty()) {
+		String::Utf8Value error(run_try_catch.Exception());
+
+		std::string err_msg = *error;
+		Logger::write("[v8] Runtime error: " + err_msg, Logger::LogLevel::Debug);
+		ah->send_message(channel_id, ":warning: **Runtime error:** `" + err_msg + "`");
 
 		return;
 	}
 
-	// run
-	script->Run(context);
 	Logger::write("[v8] Script compiled and run", Logger::LogLevel::Debug);
 
-	ah->send_message(channel_id, print_text);
-	print_text = "";
+	if (print_text != "") {
+		ah->send_message(channel_id, print_text);
+		print_text = "";
+	}
 }
 
 void V8Instance::js_print(const v8::FunctionCallbackInfo<v8::Value> &args) {