internal/format/packidx/bloom: Add

1 files changed, 108 insertions, 0 deletions

diff --git a/internal/format/packidx/bloom/write_test.go b/internal/format/packidx/bloom/write_test.go
new file mode 100644
index 00000000..18532a33
--- /dev/null
+++ b/internal/format/packidx/bloom/write_test.go
@@ -0,0 +1,108 @@
+package bloom_test
+
+import (
+	"bytes"
+	"errors"
+	"testing"
+
+	"lindenii.org/go/furgit/internal/format/packidx/bloom"
+	"lindenii.org/go/furgit/object/id"
+)
+
+func TestRecommendParams(t *testing.T) {
+	t.Parallel()
+
+	for _, format := range id.SupportedObjectFormats() {
+		t.Run(format.String(), func(t *testing.T) {
+			t.Parallel()
+
+			for _, n := range []int{0, 1, 1000, 10000, 1000000} {
+				bucketCount, k, err := bloom.RecommendParams(format, n)
+				if err != nil {
+					t.Fatalf("n=%d: %v", n, err)
+				}
+
+				if bucketCount == 0 || bucketCount&(bucketCount-1) != 0 {
+					t.Errorf("n=%d: bucket count %d not a power of two", n, bucketCount)
+				}
+
+				_, err = bloom.NewBuilder(format, bucketCount, k)
+				if err != nil {
+					t.Errorf("n=%d: recommended parameters rejected: %v", n, err)
+				}
+			}
+		})
+	}
+}
+
+func TestNewBuilderRejects(t *testing.T) {
+	t.Parallel()
+
+	cases := []struct {
+		name        string
+		bucketCount uint32
+		k           uint16
+	}{
+		{"zero buckets", 0, 8},
+		{"non power of two", 3, 8},
+		{"zero probe count", 4, 0},
+	}
+
+	for _, format := range id.SupportedObjectFormats() {
+		t.Run(format.String(), func(t *testing.T) {
+			t.Parallel()
+
+			for _, tc := range cases {
+				t.Run(tc.name, func(t *testing.T) {
+					t.Parallel()
+
+					_, err := bloom.NewBuilder(format, tc.bucketCount, tc.k)
+					if !errors.Is(err, bloom.ErrInvalidParameters) {
+						t.Fatalf("error = %v, want ErrInvalidParameters", err)
+					}
+				})
+			}
+		})
+	}
+}
+
+func TestAddBadLength(t *testing.T) {
+	t.Parallel()
+
+	builder, err := bloom.NewBuilder(id.ObjectFormatSHA256, 4, 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer func() {
+		if recover() == nil {
+			t.Fatal("Add did not panic on a short object ID")
+		}
+	}()
+
+	builder.Add(make([]byte, id.ObjectFormatSHA256.Size()-1))
+}
+
+func TestWriteTo(t *testing.T) {
+	t.Parallel()
+
+	builder, err := bloom.NewBuilder(id.ObjectFormatSHA256, 4, 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var buf bytes.Buffer
+
+	n, err := builder.WriteTo(&buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if int(n) != len(builder.Bytes()) {
+		t.Fatalf("WriteTo wrote %d bytes, want %d", n, len(builder.Bytes()))
+	}
+
+	if !bytes.Equal(buf.Bytes(), builder.Bytes()) {
+		t.Fatal("WriteTo output differs from Bytes")
+	}
+}