Fix some bugs (with functions)

Author: bensku

src/main/java/ch/njol/skript/lang/TriggerItem.java

@@ -107,8 +107,10 @@ public final static boolean walk(final TriggerItem start, final Event e) {
 			if (ex.getStackTrace().length != 0) // empty exceptions have already been printed
 				Skript.exception(ex, i);
 		} finally {
-			assert timing != null;
-			timing.stop(); // Whatever happened, end the timing
+			if (Timings.enabled()) {
+				assert timing != null;
+				timing.stop(); // Whatever happened, end the timing
+			}
 		}
 		return false;
 	}

src/main/java/ch/njol/skript/lang/function/FunctionReference.java

@@ -78,6 +78,16 @@ public boolean validateFunction(final boolean first) {
 			else
 				Skript.error("The function '" + functionName + "' was deleted or renamed, but is still used in other script(s)."
 						+ " These will continue to use the old version of the function until Skript restarts.");
+			
+			function = (Function<? extends T>) new Function<Object>("empty_placeholder", new Parameter<?>[0], null, true) {
+
+				@Override
+				@Nullable
+				public Object[] execute(FunctionEvent e, Object[][] params) {
+					return null;
+				}
+				
+			};
 			return false;
 		}
 		if (newFunc == function)

src/main/java/ch/njol/skript/lang/function/ScriptFunction.java

@@ -24,6 +24,7 @@
 import org.eclipse.jdt.annotation.Nullable;
 
 import ch.njol.skript.ScriptLoader;
+import ch.njol.skript.Skript;
 import ch.njol.skript.classes.ClassInfo;
 import ch.njol.skript.config.SectionNode;
 import ch.njol.skript.effects.EffReturn;
@@ -66,6 +67,7 @@ public ScriptFunction(final String name, final Parameter<?>[] parameters, final
 	 * @param value
 	 */
 	public final void setReturnValue(final FunctionEvent e, final @Nullable T[] value) {
+		Skript.info("Trigger is " + trigger.toString());
 		assert !returnValueSet;
 		returnValueSet = true;
 		returnValue = value;

src/main/java/ch/njol/skript/util/WeatherType.java

@@ -74,7 +74,7 @@ public final static WeatherType parse(final String s) {
 
 	public static WeatherType fromWorld(final World world) {
 		assert world != null;
-		if (world.isThundering())
+		if (world.isThundering() && world.hasStorm()) // Sometimes thundering but no storm
 			return THUNDER;
 		if (world.hasStorm())
 			return RAIN;