Immediately blow up if the user passes incorrect query params

Summary: If state.selectedId is null, or otherwise cannot find item, don't throw exception

Test Plan: Run tests

Reviewers: evan

Reviewed By: evan

Differential Revision: https://review.inboxapp.com/D1373

internal_packages/thread-list/lib/draft-list.cjsx

@@ -88,6 +88,8 @@ DraftList = React.createClass
 
   _onShiftSelectedIndex: (delta) ->
     item = _.find @state.items, (draft) => draft.id is @state.selectedId
+    return unless item
+
     index = if item then @state.items.indexOf(item) else -1
     index = Math.max(0, Math.min(index + delta, @state.items.length-1))
     @setState
@@ -95,6 +97,7 @@ DraftList = React.createClass
 
   _onDeleteSelected: ->
     item = _.find @state.items, (draft) => draft.id is @state.selectedId
+    return unless item
 
     DatabaseStore.localIdForModel(item).then (localId) ->
       Actions.destroyDraft(localId)

src/component-registry.coffee

@@ -28,7 +28,7 @@ Mixin =
       @setState getViewsByName(@components)
 
   componentWillUnmount: ->
-    @_componentUnlistener()
+    @_componentUnlistener() if @_componentUnlistener
 
 # Internal representation of components
 class Component

src/flux/stores/database-store.coffee

@@ -288,16 +288,20 @@ DatabaseStore = Reflux.createStore
   # ActiveRecord-style Querying
 
   find: (klass, id) ->
-    throw (new Error "find takes a string Id. You may have intended to use findBy.") unless _.isString(id)
+    throw new Error("You must provide a class to findByLocalId") unless klass
+    throw new Error("find takes a string id. You may have intended to use findBy.") unless _.isString(id)
     new ModelQuery(klass, @).where({id:id}).one()
 
   findBy: (klass, predicates = []) ->
+    throw new Error("You must provide a class to findBy") unless klass
     new ModelQuery(klass, @).where(predicates).one()
 
   findAll: (klass, predicates = []) ->
+    throw new Error("You must provide a class to findAll") unless klass
     new ModelQuery(klass, @).where(predicates)
 
   count: (klass, predicates = []) ->
+    throw new Error("You must provide a class to count") unless klass
     new ModelQuery(klass, @).where(predicates).count()
 
   # Support for Local IDs
@@ -306,12 +310,17 @@ DatabaseStore = Reflux.createStore
   # (like body, stored in a separate table) are always included.
   #
   findByLocalId: (klass, localId) ->
+    return Promise.reject(new Error("You must provide a class to findByLocalId")) unless klass
+    return Promise.reject(new Error("You must provide a local Id to findByLocalId")) unless localId
+
     new Promise (resolve, reject) =>
       @find(LocalLink, localId).then (link) =>
         return reject("Find by local ID lookup failed") unless link
         query = @find(klass, link.objectId).includeAll().then(resolve)
 
   bindToLocalId: (model, localId) ->
+    return Promise.reject(new Error("You must provide a model to bindToLocalId")) unless model
+
     new Promise (resolve, reject) =>
       unless localId
         if isTempId(model.id)
@@ -325,10 +334,11 @@ DatabaseStore = Reflux.createStore
       .catch(reject)
 
   localIdForModel: (model) ->
+    return Promise.reject(new Error("You must provide a model to localIdForModel")) unless model
+
     new Promise (resolve, reject) =>
       if @_localIdLookupCache[model.id]
-        resolve(@_localIdLookupCache[model.id])
-        return
+        return resolve(@_localIdLookupCache[model.id])
 
       @findBy(LocalLink, {objectId: model.id}).then (link) =>
         if link