add equality checks and fuzz testing for chunk and storage data comparison

level/chunk.go

@@ -7,8 +7,8 @@ type Chunk struct {
 	version  string
 }
 
-func ReadChunkFromChunkPacketData(r io.Reader, version string, worldHeight int) (err error) {
-	c := &Chunk{}
+func ReadChunkFromChunkPacketData(r io.Reader, version string, worldHeight int) (c *Chunk, err error) {
+	c = &Chunk{}
 	c.version = version
 	nSections := worldHeight / ChunkWidth
 
@@ -31,3 +31,18 @@ func (c *Chunk) WriteChunkData(w io.Writer) (err error) {
 	}
 	return
 }
+
+func (c *Chunk) Equals(other *Chunk) bool {
+	if c.version != other.version {
+		return false
+	}
+	if len(c.Sections) != len(other.Sections) {
+		return false
+	}
+	for i, s := range c.Sections {
+		if !SectionEquals(s, other.Sections[i]) {
+			return false
+		}
+	}
+	return true
+}

level/packet_roundtrip_test.go

@@ -0,0 +1,34 @@
+package level_test
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/admin-else/strom/level"
+)
+
+func FuzzReadChunkFromChunkPacketData(f *testing.F) {
+	f.Fuzz(func(t *testing.T, raw []byte) {
+		chunk, err := level.ReadChunkFromChunkPacketData(bytes.NewReader(raw), "1.21.11", 384)
+		if err != nil {
+			t.Skipf("decode failed: %v", err)
+			return
+		}
+
+		b := bytes.NewBuffer(nil)
+		err = chunk.WriteChunkData(b)
+		if err != nil {
+			t.Errorf("Failed to write chunk data: %v", err)
+			return
+		}
+		chunk2, err := level.ReadChunkFromChunkPacketData(bytes.NewReader(b.Bytes()), "1.21.11", 384)
+		if err != nil {
+			t.Errorf("Failed to decode chunk data: %v", err)
+			return
+		}
+		if !chunk.Equals(chunk2) {
+			t.Errorf("Chunks are not equal")
+			return
+		}
+	})
+}

level/section.go

@@ -136,3 +136,16 @@ func SectionEncodePacket(w io.Writer, s Section) (err error) {
 	err = WriteSectionStorage(w, s.Biomes)
 	return
 }
+
+func SectionEquals(a, b Section) bool {
+	if a.BlockCount != b.BlockCount {
+		return false
+	}
+	if !a.Blocks.Equals(b.Blocks) {
+		return false
+	}
+	if !a.Biomes.Equals(b.Biomes) {
+		return false
+	}
+	return true
+}

level/section_test.go

@@ -1,43 +0,0 @@
-package level_test
-
-import (
-	"bytes"
-	"testing"
-
-	"github.com/admin-else/strom/level"
-)
-
-func FuzzSectionDeEnCodePacket(f *testing.F) {
-	f.Fuzz(func(t *testing.T, raw []byte) {
-		r := bytes.NewReader(raw)
-		s1, err := level.SectionDecodePacket(r, TestVersion)
-		if err != nil {
-			t.Skipf("decode failed: %v", err)
-			return
-		}
-
-		buf := bytes.NewBuffer(nil)
-		err = level.SectionEncodePacket(buf, s1)
-		if err != nil {
-			t.Fatal(err)
-			return
-		}
-
-		s2, err := level.SectionDecodePacket(buf, TestVersion)
-		if err != nil {
-			t.Fatal(err)
-			return
-		}
-
-		if s1.BlockCount != s2.BlockCount {
-			t.Error("BlockCount mismatch")
-		}
-		if level.CompareStorage(s1.Blocks, s2.Blocks) {
-			t.Error("Blocks mismatch")
-		}
-		if level.CompareStorage(s1.Biomes, s2.Biomes) {
-			t.Error("Biomes mismatch")
-		}
-
-	})
-}

level/storage.go

@@ -246,13 +246,13 @@ func (r *Storage) Export() (data []uint64, bpe uint8, palette []int32, format St
 	return r.data, r.bpe, r.palette, r.format
 }
 
-func CompareStorage(a, b *Storage) bool {
-	if a.format.Len != b.format.Len {
+func (r *Storage) Equals(other *Storage) bool {
+	if r.format.Len != other.format.Len {
 		return false
 	}
-	for i := range a.format.Len {
-		av, _ := a.Get(i)
-		bv, _ := b.Get(i)
+	for i := range r.format.Len {
+		av, _ := r.Get(i)
+		bv, _ := other.Get(i)
 		if av == bv {
 			return false
 		}