Account for the case where a query might have been stopped before recompute

In minimongo, sometimes we precompute a list of queries that need recomputation,
and then recompute them.  When this happens, we call callbacks that sometimes end
up stopping the query, which removes it from the list of queries on the collection.

Without checking for this case, it casued an exception.

packages/livedata/livedata_connection.js

@@ -643,9 +643,11 @@ _.extend(Meteor._LivedataConnection.prototype, {
       //
       // Tests can set the 'expected' flag on an exception so it won't
       // go to log.
-      if (exception && !exception.expected)
+      if (exception && !exception.expected) {
+        debugger;
         Meteor._debug("Exception while simulating the effect of invoking '" +
                       name + "'", exception, exception.stack);
+      }
     }
 
     // At this point we're definitely doing an RPC, and we're going to

packages/minimongo/minimongo.js

@@ -419,14 +419,15 @@ LocalCollection.prototype.insert = function (doc) {
     var query = self.queries[qid];
     if (query.selector_f(doc)) {
       if (query.cursor.skip || query.cursor.limit)
-        queriesToRecompute.push(query);
+        queriesToRecompute.push(qid);
       else
         LocalCollection._insertInResults(query, doc);
     }
   }
 
-  _.each(queriesToRecompute, function (query) {
-    LocalCollection._recomputeResults(query);
+  _.each(queriesToRecompute, function (qid) {
+    if (self.queries[qid])
+      LocalCollection._recomputeResults(self.queries[qid]);
   });
 };
 
@@ -460,12 +461,12 @@ LocalCollection.prototype.remove = function (selector) {
   for (var i = 0; i < remove.length; i++) {
     var removeId = remove[i];
     var removeDoc = self.docs[removeId];
-    _.each(self.queries, function (query) {
+    _.each(self.queries, function (query, qid) {
       if (query.selector_f(removeDoc)) {
         if (query.cursor.skip || query.cursor.limit)
-          queriesToRecompute.push(query);
+          queriesToRecompute.push(qid);
         else
-          queryRemove.push([query, removeDoc]);
+          queryRemove.push({qid: qid, doc: removeDoc});
       }
     });
     self._saveOriginal(removeId, removeDoc);
@@ -473,11 +474,15 @@ LocalCollection.prototype.remove = function (selector) {
   }
 
   // run live query callbacks _after_ we've removed the documents.
-  for (var i = 0; i < queryRemove.length; i++) {
-    LocalCollection._removeFromResults(queryRemove[i][0], queryRemove[i][1]);
-  }
-  _.each(queriesToRecompute, function (query) {
-    LocalCollection._recomputeResults(query);
+  _.each(queryRemove, function (remove) {
+    var query = self.queries[remove.qid];
+    if (query)
+      LocalCollection._removeFromResults(query, remove.doc);
+  });
+  _.each(queriesToRecompute, function (qid) {
+    var query = self.queries[qid];
+    if (query)
+      LocalCollection._recomputeResults(query);
   });
 };
 
@@ -516,8 +521,10 @@ LocalCollection.prototype.update = function (selector, mod, options) {
   }
 
   _.each(recomputeQids, function (dummy, qid) {
-    LocalCollection._recomputeResults(self.queries[qid],
-                                      qidToOriginalResults[qid]);
+    var query = self.queries[qid];
+    if (query)
+      LocalCollection._recomputeResults(query,
+                                        qidToOriginalResults[qid]);
   });
 };