Basic tests and trying to fix address sanitizer errors

src/plugin_tests.cpp

@@ -1,3 +1,4 @@
+#if PLUGIN_TESTS
 bool Testing = true;
 
 void Wait(mco_coro *co) {
@@ -37,4 +38,19 @@ void CO_FirstTest(mco_coro *co) {
     {Event ev = {};ev.kind = EVENT_TEXT_INPUT; ev.xwindow = 1412; ev.ywindow = 1032; ev.xmouse = 1234; ev.ymouse = 594; ev.text = "f"; Add(&EventPlayback, ev);}
     Wait(co);
 
+    String16 result = uR"FOO(
+
+
+
+
+
+
+Memes and stuff)FOO";
+    BSet set = GetBSet(PrimaryWindowID);
+    Assert(AreEqual(result, GetString(set.buffer)));
+
+    void CMD_QuitWithoutSaving();
+    CMD_QuitWithoutSaving();
+
 } RegisterCoroutineCommand(CO_FirstTest, "", "Basic tests");
+#endif