move cmd/pruning to pruning, as it's independent of the command implementation

pruning/pruning_test.go

@@ -0,0 +1,112 @@
+package pruning
+
+import (
+	"fmt"
+	"github.com/stretchr/testify/assert"
+	"testing"
+	"time"
+)
+
+type stubSnap struct {
+	name       string
+	replicated bool
+	date       time.Time
+}
+
+func (s stubSnap) Name() string { return s.name }
+
+func (s stubSnap) Replicated() bool { return s.replicated }
+
+func (s stubSnap) Date() time.Time { return s.date }
+
+type testCase struct {
+	inputs   []Snapshot
+	rules    []KeepRule
+	exp, eff map[string]bool
+}
+
+func testTable(tcs map[string]testCase, t *testing.T) {
+	mapEqual := func(a, b map[string]bool) bool {
+		if len(a) != len(b) {
+			return false
+		}
+		for k, v := range a {
+			if w, ok := b[k]; !ok || v != w {
+				return false
+			}
+		}
+		return true
+	}
+
+	for name := range tcs {
+		t.Run(name, func(t *testing.T) {
+			tc := tcs[name]
+			remove := PruneSnapshots(tc.inputs, tc.rules)
+			tc.eff = make(map[string]bool)
+			for _, s := range remove {
+				tc.eff[s.Name()] = true
+			}
+			assert.True(t, mapEqual(tc.exp, tc.eff), fmt.Sprintf("is %v but should be %v", tc.eff, tc.exp))
+		})
+	}
+}
+
+func TestPruneSnapshots(t *testing.T) {
+
+	inputs := map[string][]Snapshot{
+		"s1": []Snapshot{
+			stubSnap{name: "foo_123"},
+			stubSnap{name: "foo_456"},
+			stubSnap{name: "bar_123"},
+		},
+	}
+
+	tcs := map[string]testCase{
+		"simple": {
+			inputs: inputs["s1"],
+			rules: []KeepRule{
+				MustKeepRegex("foo_"),
+			},
+			exp: map[string]bool{
+				"bar_123": true,
+			},
+		},
+		"multipleRules": {
+			inputs: inputs["s1"],
+			rules: []KeepRule{
+				MustKeepRegex("foo_"),
+				MustKeepRegex("bar_"),
+			},
+			exp: map[string]bool{},
+		},
+		"onlyThoseRemovedByAllAreRemoved": {
+			inputs: inputs["s1"],
+			rules: []KeepRule{
+				MustKeepRegex("notInS1"), // would remove all
+				MustKeepRegex("bar_"),    // would remove all but bar_, i.e. foo_.*
+			},
+			exp: map[string]bool{
+				"foo_123": true,
+				"foo_456": true,
+			},
+		},
+		"noRulesKeepsAll": {
+			inputs: inputs["s1"],
+			rules:  []KeepRule{},
+			exp: map[string]bool{
+				"foo_123": true,
+				"foo_456": true,
+				"bar_123": true,
+			},
+		},
+		"noSnaps": {
+			inputs: []Snapshot{},
+			rules: []KeepRule{
+				MustKeepRegex("foo_"),
+			},
+			exp: map[string]bool{},
+		},
+	}
+
+	testTable(tcs, t)
+}