1 files changed, 145 insertions, 0 deletions
diff --git a/src/go/collectors/go.d.plugin/pkg/metrics/unique_counter_test.go b/src/go/collectors/go.d.plugin/pkg/metrics/unique_counter_test.go
new file mode 100644
index 000000000..b9439c9a3
--- /dev/null
+++ b/src/go/collectors/go.d.plugin/pkg/metrics/unique_counter_test.go
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package metrics
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestHyperLogLogUniqueCounter_Value(t *testing.T) {
+	for _, useHLL := range []bool{true, false} {
+		t.Run(fmt.Sprintf("HLL=%v", useHLL), func(t *testing.T) {
+			c := NewUniqueCounter(useHLL)
+			assert.Equal(t, 0, c.Value())
+
+			c.Insert("foo")
+			assert.Equal(t, 1, c.Value())
+
+			c.Insert("foo")
+			assert.Equal(t, 1, c.Value())
+
+			c.Insert("bar")
+			assert.Equal(t, 2, c.Value())
+
+			c.Insert("baz")
+			assert.Equal(t, 3, c.Value())
+
+			c.Reset()
+			assert.Equal(t, 0, c.Value())
+
+			c.Insert("foo")
+			assert.Equal(t, 1, c.Value())
+		})
+	}
+}
+
+func TestHyperLogLogUniqueCounter_WriteTo(t *testing.T) {
+	for _, useHLL := range []bool{true, false} {
+		t.Run(fmt.Sprintf("HLL=%v", useHLL), func(t *testing.T) {
+			c := NewUniqueCounterVec(useHLL)
+			c.Get("a").Insert("foo")
+			c.Get("a").Insert("bar")
+			c.Get("b").Insert("foo")
+
+			m := map[string]int64{}
+			c.WriteTo(m, "pi", 100, 1)
+			assert.Len(t, m, 2)
+			assert.EqualValues(t, 200, m["pi_a"])
+			assert.EqualValues(t, 100, m["pi_b"])
+		})
+	}
+}
+
+func TestUniqueCounterVec_Reset(t *testing.T) {
+	for _, useHLL := range []bool{true, false} {
+		t.Run(fmt.Sprintf("HLL=%v", useHLL), func(t *testing.T) {
+			c := NewUniqueCounterVec(useHLL)
+			c.Get("a").Insert("foo")
+			c.Get("a").Insert("bar")
+			c.Get("b").Insert("foo")
+
+			assert.Equal(t, 2, len(c.Items))
+			assert.Equal(t, 2, c.Get("a").Value())
+			assert.Equal(t, 1, c.Get("b").Value())
+
+			c.Reset()
+			assert.Equal(t, 2, len(c.Items))
+			assert.Equal(t, 0, c.Get("a").Value())
+			assert.Equal(t, 0, c.Get("b").Value())
+		})
+	}
+}
+
+func BenchmarkUniqueCounter_Insert(b *testing.B) {
+	benchmarks := []struct {
+		name        string
+		same        bool
+		hyperloglog bool
+		nop         bool
+	}{
+
+		{"map-same", true, false, false},
+		{"hll-same", true, true, false},
+
+		{"nop", false, false, true},
+		{"map-diff", false, false, false},
+		{"hll-diff", false, true, false},
+	}
+	for _, bm := range benchmarks {
+		b.Run(bm.name, func(b *testing.B) {
+			c := NewUniqueCounter(bm.hyperloglog)
+			if bm.same {
+				for i := 0; i < b.N; i++ {
+					c.Insert("foo")
+				}
+			} else if bm.nop {
+				for i := 0; i < b.N; i++ {
+					strconv.Itoa(i)
+				}
+			} else {
+				for i := 0; i < b.N; i++ {
+					c.Insert(strconv.Itoa(i))
+				}
+			}
+		})
+	}
+}
+
+func BenchmarkUniqueCounterVec_Insert(b *testing.B) {
+	benchmarks := []struct {
+		name        string
+		same        bool
+		hyperloglog bool
+		nop         bool
+	}{
+
+		{"map-same", true, false, false},
+		{"hll-same", true, true, false},
+
+		{"nop", false, false, true},
+		{"map-diff", false, false, false},
+		{"hll-diff", false, true, false},
+	}
+	for _, bm := range benchmarks {
+		b.Run(bm.name, func(b *testing.B) {
+			c := NewUniqueCounterVec(bm.hyperloglog)
+			if bm.same {
+				for i := 0; i < b.N; i++ {
+					c.Get("a").Insert("foo")
+				}
+			} else if bm.nop {
+				for i := 0; i < b.N; i++ {
+					strconv.Itoa(i)
+				}
+			} else {
+				for i := 0; i < b.N; i++ {
+					c.Get("a").Insert(strconv.Itoa(i))
+				}
+			}
+		})
+	}
+}