pruning: fix tests + implement 'not_replicated' and 'keep_regex' keep rule

tests expected that a KeepRule returns a *keep* list whereas it
actually returns a *destroy* list.

pruning/keep_not_replicated_test.go

@@ -0,0 +1,39 @@
+package pruning
+
+import (
+	"testing"
+)
+
+func TestNewKeepNotReplicated(t *testing.T) {
+
+	inputs := map[string][]Snapshot{
+		"s1": []Snapshot{
+			stubSnap{name: "1", replicated: true},
+			stubSnap{name: "2", replicated: false},
+			stubSnap{name: "3", replicated: true},
+		},
+		"s2": []Snapshot{},
+	}
+
+	tcs := map[string]testCase{
+		"destroysOnlyReplicated": {
+			inputs: inputs["s1"],
+			rules: []KeepRule{
+				NewKeepNotReplicated(),
+			},
+			expDestroy: map[string]bool{
+				"1": true, "3": true,
+			},
+		},
+		"empty": {
+			inputs: inputs["s2"],
+			rules: []KeepRule{
+				NewKeepNotReplicated(),
+			},
+			expDestroy: map[string]bool{},
+		},
+	}
+
+	testTable(tcs, t)
+
+}