basic pigeon-holing of issues into days

src/issues.coffee

@@ -52,4 +52,19 @@ module.exports =
             cb null, warnings, filtered
         
         catch err
-            return cb err, warnings
+            return cb err, warnings
+
+    # Map a collection of closed issues into days.
+    'into_days': (collection, cb) ->
+        days = {}
+        for issue in collection
+            { state, number, closed_at } = issue
+            number ?= '?'
+            return "Issue ##{number} does not have a `closed_at` parameter" unless closed_at
+            unless matches = closed_at.match /^(\d{4}-\d{2}-\d{2})T(.*)/
+                return "Issue ##{number} does not match the `closed_at` pattern"
+            [ date, time ] = matches[1...]
+            days[date] ?= []
+            days[date].push issue
+
+        cb null, days

test/issues.coffee

@@ -181,4 +181,21 @@ module.exports =
             assert.ifError err
             assert.equal warn.length, 1
             assert.equal data.length, 1
+            done.call null
+
+    'organize issues into days': (done) ->
+        issues.into_days [
+            { number: 1, closed_at: '2013-05-09T10:04:53Z' }
+            { number: 2, closed_at: '2013-05-09T09:04:53Z' }
+            { number: 3, closed_at: '2013-05-10T09:04:53Z' }
+        ], (err, data) ->
+            assert.ifError err
+            assert.deepEqual data,
+                '2013-05-09': [
+                    { number: 1, closed_at: '2013-05-09T10:04:53Z' }
+                    { number: 2, closed_at: '2013-05-09T09:04:53Z' }
+                ]
+                '2013-05-10': [
+                    { number: 3, closed_at: '2013-05-10T09:04:53Z' }
+                ]
             done.call null