2 files changed, 21 insertions, 0 deletions
diff --git a/plumbing/protocol/packp/capability/list.go b/plumbing/protocol/packp/capability/list.go
index 2847580..69fdb51 100644
--- a/plumbing/protocol/packp/capability/list.go
+++ b/plumbing/protocol/packp/capability/list.go
@@ -167,6 +167,16 @@ func (l *List) Delete(capability Capability) {
 	}
 }
 
+// All returns a slice with all defined capabilities.
+func (l *List) All() []Capability {
+	var cs []Capability
+	for _, key := range l.sort {
+		cs = append(cs, Capability(key))
+	}
+
+	return cs
+}
+
 // String generates the capabilities strings, the capabilities are sorted in
 // insertion order
 func (l *List) String() string {
diff --git a/plumbing/protocol/packp/capability/list_test.go b/plumbing/protocol/packp/capability/list_test.go
index 42f0179..0a0ad26 100644
--- a/plumbing/protocol/packp/capability/list_test.go
+++ b/plumbing/protocol/packp/capability/list_test.go
@@ -171,3 +171,14 @@ func (s *SuiteCapabilities) TestAddErrMultipleArgumentsAtTheSameTime(c *check.C)
 	err := cap.Add(Agent, "foo", "bar")
 	c.Assert(err, check.Equals, ErrMultipleArguments)
 }
+
+func (s *SuiteCapabilities) TestAll(c *check.C) {
+	cap := NewList()
+	c.Assert(NewList().All(), check.IsNil)
+
+	cap.Add(Agent, "foo")
+	c.Assert(cap.All(), check.DeepEquals, []Capability{Agent})
+
+	cap.Add(OFSDelta)
+	c.Assert(cap.All(), check.DeepEquals, []Capability{Agent, OFSDelta})
+}