Fix listeners with modifiers #123
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…o modifiers
Previously:
db.ref('/messages').on('child_added')
db.ref('/messages').limitToFirst(1).on('child_added')
db.ref('/messages').limitToLast(1).on('child_added')
would add native listeners for the appropiarate queries, but when
ANY of the three fired a child_added, than ALL three would receive it
e.g. the limitToFirst child_added would get called when the *last* element changed
We now keep track of the listeners by path as well as modifierString,
and to a lesser extent, by eventType
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Is this ready to go? |
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Not quite- I'll make a new PR soon which will include the immutable refs/queries as well as these commits. |
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Fix listeners with modifiers reusing handles with the same path but no modifiers
We now keep track of the listeners by path as well as modifierString, and to a lesser extent, by eventType
Previously, if we have:
a)
db.ref('/messages').on('child_added')b)
db.ref('/messages').limitToFirst(1).on('child_added')c)
db.ref('/messages').limitToLast(1).on('child_added')In short:
If we were to push a new message onto /messages, the 'b' query above with limitToFirst would fire its child_added listenerwould get called, despite only the last element having changed
Longer explanation:
it will reuse the same javascript subscription, and it will create 3 unique path+modifier references in the native code, to which we'll attach:
ios: only the appropriate listener
android: the multi-listener for all eventTypes
these listeners will fire correctly whenever (compare with a, b & c above):
a) anything gets added
b) when the last item changes
c) when the first item changes
but when any of these three listeners emit an event, all 3 will receive it