Fix nits

graph/mongo/lru.go

@@ -16,7 +16,6 @@ package mongo
 
 import (
 	"container/list"
-	"fmt"
 )
 
 // TODO(kortschak) Reimplement without container/list.
@@ -49,9 +48,6 @@ func (lru *cache) Put(key string, value interface{}) {
 		lru.removeOldest()
 	}
 	lru.priority.PushFront(kv{key: key, value: value})
-	if lru.priority == nil {
-		fmt.Println("wat")
-	}
 	lru.cache[key] = lru.priority.Front()
 }
 
@@ -60,7 +56,7 @@ func (lru *cache) Get(key string) (interface{}, bool) {
 		lru.priority.MoveToFront(element)
 		return element.Value.(kv).value, true
 	}
-	return "", false
+	return nil, false
 }
 
 func (lru *cache) removeOldest() {

graph/mongo/quadstore.go

@@ -382,7 +382,6 @@ func (qs *QuadStore) Type() string {
 
 func (qs *QuadStore) getSize(collection string, constraint bson.M) (int64, error) {
 	var size int
-	var err error
 	bytes, err := bson.Marshal(constraint)
 	if err != nil {
 		glog.Errorf("Couldn't marshal internal constraint")

graph/mongo/quadstore_iterator_optimize.go

@@ -48,12 +48,12 @@ func (qs *QuadStore) optimizeAndIterator(it *iterator.And) (graph.Iterator, bool
 	}
 
 	newAnd := iterator.NewAnd(qs)
-	var firstmongo *Iterator
+	var mongoIt *Iterator
 	for _, it := range it.SubIterators() {
 		switch it.Type() {
 		case mongoType:
-			if firstmongo == nil {
-				firstmongo = it.(*Iterator)
+			if mongoIt == nil {
+				mongoIt = it.(*Iterator)
 			} else {
 				newAnd.AddSubIterator(it)
 			}
@@ -63,30 +63,30 @@ func (qs *QuadStore) optimizeAndIterator(it *iterator.And) (graph.Iterator, bool
 			newAnd.AddSubIterator(it)
 		}
 	}
-	mongostats := firstmongo.Stats()
+	stats := mongoIt.Stats()
 
 	lset := []graph.Linkage{
 		{
-			Dir:    firstmongo.dir,
-			Values: []graph.Value{qs.ValueOf(firstmongo.name)},
+			Dir:    mongoIt.dir,
+			Values: []graph.Value{qs.ValueOf(mongoIt.name)},
 		},
 	}
 
-	ltocount := 0
+	n := 0
 	for _, it := range it.SubIterators() {
 		if it.Type() == graph.LinksTo {
 			lto := it.(*iterator.LinksTo)
 			// Is it more effective to do the replacement, or let the mongo check the linksto?
 			ltostats := lto.Stats()
-			if (ltostats.ContainsCost+mongostats.NextCost)*mongostats.Size > (ltostats.NextCost+mongostats.ContainsCost)*ltostats.Size {
+			if (ltostats.ContainsCost+stats.NextCost)*stats.Size > (ltostats.NextCost+stats.ContainsCost)*ltostats.Size {
 				continue
 			}
 			newLto := NewLinksTo(qs, lto.SubIterators()[0], "quads", lto.Direction(), lset)
 			newAnd.AddSubIterator(newLto)
-			ltocount++
+			n++
 		}
 	}
-	if ltocount == 0 {
+	if n == 0 {
 		return it, false
 	}