test keep last n pruning

cmd/pruning/keep_last_n_test.go

@@ -0,0 +1,77 @@
+package pruning
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+	"time"
+)
+
+func TestKeepLastN(t *testing.T) {
+
+	o := func(minutes int) time.Time {
+		return time.Unix(123, 0).Add(time.Duration(minutes) * time.Minute)
+	}
+
+	inputs := map[string][]Snapshot{
+		"s1": []Snapshot{
+			stubSnap{name: "1", date: o(10)},
+			stubSnap{name: "2", date: o(20)},
+			stubSnap{name: "3", date: o(15)},
+			stubSnap{name: "4", date: o(30)},
+			stubSnap{name: "5", date: o(30)},
+		},
+		"s2": []Snapshot{},
+	}
+
+	tcs := map[string]testCase{
+		"keep2": {
+			inputs: inputs["s1"],
+			rules: []KeepRule{
+				KeepLastN{2},
+			},
+			exp: map[string]bool{
+				"4": true, "5": true,
+			},
+		},
+		"keep1": { // Keep one of two with same time
+			inputs: inputs["s1"],
+			rules: []KeepRule{
+				KeepLastN{1},
+			},
+			exp: map[string]bool{
+				"4": true, //5 would be ok too
+			},
+		},
+		"keepMany": {
+			inputs: inputs["s1"],
+			rules: []KeepRule{
+				KeepLastN{100},
+			},
+			exp: map[string]bool{
+				"1": true,
+				"2": true,
+				"3": true,
+				"4": true,
+				"5": true,
+			},
+		},
+		"empty": {
+			inputs: inputs["s2"],
+			rules: []KeepRule{
+				KeepLastN{100},
+			},
+			exp: map[string]bool{},
+		},
+	}
+
+	testTable(tcs, t)
+
+	t.Run("mustBePositive", func(t *testing.T) {
+		var err error
+		_, err = NewKeepLastN(0)
+		assert.Error(t, err)
+		_, err = NewKeepLastN(-5)
+		assert.Error(t, err)
+	})
+
+}