From f2649376c5d958fa3041785cb25f2471241e5c61 Mon Sep 17 00:00:00 2001
From: Dan Vanderkam <danvdk@gmail.com>
Date: Mon, 9 Mar 2015 19:19:47 -0400
Subject: [PATCH] passes flow checks

---
 lib/underscore.js       | 6 ++++++
 src/Root.js             | 6 ++++--
 src/TwoBitDataSource.js | 6 +++++-
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/lib/underscore.js b/lib/underscore.js
index e1e9e4a0..1007f04e 100644
--- a/lib/underscore.js
+++ b/lib/underscore.js
@@ -3,5 +3,11 @@
 declare module "underscore" {
   declare function findWhere<T>(list: Array<T>, properties: {}): ?T;
   declare function clone<T>(obj: T): T;
+
+  declare function isEqual<S, T>(a: S, b: T): boolean;
+  declare function range(a: number, b: number): Array<number>;
+  declare function extend(...o: Object): Object;
+
+  declare function chain<S>(obj: S): any;
 }
 
diff --git a/src/Root.js b/src/Root.js
index 93b6e2bf..f7ea5be9 100644
--- a/src/Root.js
+++ b/src/Root.js
@@ -6,8 +6,10 @@
 var React = require('react'),
     Controls = require('./Controls'),
     GenomeTrack = require('./GenomeTrack'),
-    types = require('./types');
     // TODO: make this an "import type" when react-tools 0.13.0 is out.
+    TwoBitDataSource = require('./TwoBitDataSource'),
+    types = require('./types');
+
 
 var Root = React.createClass({
   propTypes: {
@@ -22,7 +24,7 @@ var Root = React.createClass({
   },
   componentDidMount: function() {
     // Note: flow is unable to infer this type through `this.propTypes`.
-    var source: TwoBitDataSource = this.props.referenceSource;
+    var source = this.props.referenceSource;
     source.needContigs();
 
     source.on('contigs', () => { this.update() })
diff --git a/src/TwoBitDataSource.js b/src/TwoBitDataSource.js
index b91ee069..231ada92 100644
--- a/src/TwoBitDataSource.js
+++ b/src/TwoBitDataSource.js
@@ -20,13 +20,17 @@
 var Events = require('backbone').Events,
     _ = require('underscore');
 
+// TODO: make this an "import type" when react-tools 0.13.0 is out.
+var TwoBit = require('./TwoBit');
+
 // Factor by which to over-request data from the network.
 // If a range of 100bp is shown and this is 2.0, then 300 base pairs will be
 // requested over the network (100 * 2.0 too much)
 var EXPANSION_FACTOR = 2.0;
 
 
-var createTwoBitDataSource = function(remoteSource: TwoBit) {
+// TODO: make the return type more precise
+var createTwoBitDataSource = function(remoteSource: TwoBit): any {
   // Local cache of genomic data.
   var contigList = [];
   var basePairs = {};  // contig -> locus -> letter