change to go style vars and error msgs in lru tests

Error messages changed to use "got X; expected Y" style.
and no underscore for var names.

lru/lru_test.go

@@ -74,7 +74,7 @@ func TestRemove(t *testing.T) {
 }
 
 func TestAdd(t *testing.T) {
-	lru_cache := New(3)
+	lru := New(3)
 	items := []struct {
 		key   string
 		value string
@@ -86,10 +86,10 @@ func TestAdd(t *testing.T) {
 		{"four", "4"},
 	}
 	for _, tt := range items {
-		lru_cache.Add(tt.key, tt.value)
+		lru.Add(tt.key, tt.value)
 	}
-	if lru_cache.ll.Len() != 3 {
-		t.Fatalf("Expected 3 items; got %d items", lru_cache.ll.Len())
+	if lru.ll.Len() != 3 {
+		t.Fatalf("lru size: %d items; expected 3 items", lru.ll.Len())
 	}
 }
 
@@ -101,6 +101,6 @@ func TestAddToNilCache(t *testing.T) {
 	}
 	c.Add("foo", "bar")
 	if c.ll.Len() != 1 {
-		t.Fatalf("Expected 1 item; got %d items", c.ll.Len())
+		t.Fatalf("lru size: %d items; expected 1 item", c.ll.Len())
 	}
 }