1 files changed, 119 insertions, 0 deletions
diff --git a/pkg/targets/hash_bins_test.go b/pkg/targets/hash_bins_test.go
new file mode 100644
index 0000000..dce2ab8
--- /dev/null
+++ b/pkg/targets/hash_bins_test.go
@@ -0,0 +1,119 @@
+package targets
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func BenchmarkHexEncode1(b *testing.B) {
+	for n := 0; n <= b.N; n++ {
+		for x := uint64(0); x <= 0xf; x += 1 {
+			hexEncode(x, 1)
+		}
+	}
+}
+
+func BenchmarkHexEncode4(b *testing.B) {
+	for n := 0; n <= b.N; n++ {
+		for x := uint64(0); x <= 0xffff; x += 1 {
+			hexEncode(x, 4)
+		}
+	}
+}
+
+func TestHashBin(t *testing.T) {
+	tcs := []struct {
+		hb           *HashBin
+		roleName     string
+		hashPrefixes []string
+	}{
+		{
+			hb: &HashBin{
+				rolePrefix:  "abc_",
+				hexDigitLen: 1,
+				first:       0x0,
+				last:        0x7,
+			},
+			roleName: "abc_0-7",
+			hashPrefixes: []string{
+				"0", "1", "2", "3", "4", "5", "6", "7",
+			},
+		},
+		{
+			hb: &HashBin{
+				rolePrefix:  "abc_",
+				hexDigitLen: 2,
+				first:       0x0,
+				last:        0xf,
+			},
+			roleName: "abc_00-0f",
+			hashPrefixes: []string{
+				"00", "01", "02", "03", "04", "05", "06", "07",
+				"08", "09", "0a", "0b", "0c", "0d", "0e", "0f",
+			},
+		},
+		{
+			hb: &HashBin{
+				rolePrefix:  "cba_",
+				hexDigitLen: 4,
+				first:       0xcd,
+				last:        0xcf,
+			},
+			roleName:     "cba_00cd-00cf",
+			hashPrefixes: []string{"00cd", "00ce", "00cf"},
+		},
+		{
+			hb: &HashBin{
+				rolePrefix:  "cba_",
+				hexDigitLen: 3,
+				first:       0xc1,
+				last:        0xc1,
+			},
+			roleName:     "cba_0c1",
+			hashPrefixes: []string{"0c1"},
+		},
+	}
+
+	for i, tc := range tcs {
+		assert.Equalf(t, tc.roleName, tc.hb.RoleName(), "test case %v: RoleName()", i)
+		assert.Equalf(t, tc.hashPrefixes, tc.hb.HashPrefixes(), "test case %v: HashPrefixes()", i)
+	}
+}
+
+func TestHashBins(t *testing.T) {
+	tcs := []struct {
+		bitLen    int
+		roleNames []string
+	}{
+		{1, []string{"0-7", "8-f"}},
+		{2, []string{"0-3", "4-7", "8-b", "c-f"}},
+		{3, []string{"0-1", "2-3", "4-5", "6-7", "8-9", "a-b", "c-d", "e-f"}},
+		{4, []string{
+			"0", "1", "2", "3", "4", "5", "6", "7",
+			"8", "9", "a", "b", "c", "d", "e", "f",
+		}},
+		{5, []string{
+			"00-07", "08-0f", "10-17", "18-1f", "20-27", "28-2f", "30-37", "38-3f",
+			"40-47", "48-4f", "50-57", "58-5f", "60-67", "68-6f", "70-77", "78-7f",
+			"80-87", "88-8f", "90-97", "98-9f", "a0-a7", "a8-af", "b0-b7", "b8-bf",
+			"c0-c7", "c8-cf", "d0-d7", "d8-df", "e0-e7", "e8-ef", "f0-f7", "f8-ff",
+		}},
+	}
+	for i, tc := range tcs {
+		got := []string{}
+		hbs, err := NewHashBins("", tc.bitLen)
+		assert.NoError(t, err)
+		n := hbs.NumBins()
+		for i := uint64(0); i < n; i += 1 {
+			hb := hbs.GetBin(i)
+			got = append(got, hb.RoleName())
+		}
+		assert.Equalf(t, tc.roleNames, got, "test case %v", i)
+	}
+
+	_, err := NewHashBins("", 0)
+	assert.Error(t, err)
+	_, err = NewHashBins("", 33)
+	assert.Error(t, err)
+}