From e49afbcd2dfd3e3fb25f97ee21bf3f8ef475de76 Mon Sep 17 00:00:00 2001
From: Andrey Smirnov <Smirnov.Andrey@gmail.com>
Date: Wed, 29 Jan 2014 17:13:42 +0400
Subject: [PATCH] Snapshot dropping.

---
 debian/snapshot.go      | 26 ++++++++++++++++++++++++++
 debian/snapshot_test.go | 21 +++++++++++++++++++++
 2 files changed, 47 insertions(+)

diff --git a/debian/snapshot.go b/debian/snapshot.go
index 8984da52..221385eb 100644
--- a/debian/snapshot.go
+++ b/debian/snapshot.go
@@ -224,3 +224,29 @@ func (collection *SnapshotCollection) ForEach(handler func(*Snapshot) error) err
 func (collection *SnapshotCollection) Len() int {
 	return len(collection.list)
 }
+
+// Drop removes snapshot from collection
+func (collection *SnapshotCollection) Drop(snapshot *Snapshot) error {
+	snapshotPosition := -1
+
+	for i, s := range collection.list {
+		if s == snapshot {
+			snapshotPosition = i
+			break
+		}
+	}
+
+	if snapshotPosition == -1 {
+		panic("snapshot not found!")
+	}
+
+	collection.list[len(collection.list)-1], collection.list[snapshotPosition], collection.list =
+		nil, collection.list[len(collection.list)-1], collection.list[:len(collection.list)-1]
+
+	err := collection.db.Delete(snapshot.Key())
+	if err != nil {
+		return err
+	}
+
+	return collection.db.Delete(snapshot.RefKey())
+}
diff --git a/debian/snapshot_test.go b/debian/snapshot_test.go
index d621e476..55c9f624 100644
--- a/debian/snapshot_test.go
+++ b/debian/snapshot_test.go
@@ -170,3 +170,24 @@ func (s *SnapshotCollectionSuite) TestFindByRemoteRepoSource(c *C) {
 
 	c.Check(s.collection.ByRemoteRepoSource(repo3), DeepEquals, []*Snapshot{})
 }
+
+func (s *SnapshotCollectionSuite) TestDrop(c *C) {
+	s.collection.Add(s.snapshot1)
+	s.collection.Add(s.snapshot2)
+
+	snap, _ := s.collection.ByUUID(s.snapshot1.UUID)
+	c.Check(snap, Equals, s.snapshot1)
+
+	err := s.collection.Drop(s.snapshot1)
+	c.Check(err, IsNil)
+
+	_, err = s.collection.ByUUID(s.snapshot1.UUID)
+	c.Check(err, ErrorMatches, "snapshot .* not found")
+
+	collection := NewSnapshotCollection(s.db)
+
+	_, err = collection.ByUUID(s.snapshot1.UUID)
+	c.Check(err, ErrorMatches, "snapshot .* not found")
+
+	c.Check(func() { s.collection.Drop(s.snapshot1) }, Panics, "snapshot not found!")
+}