From c9fdf61bd91875cdc71559cd9bab8314ad8775e1 Mon Sep 17 00:00:00 2001
From: Runxi Yu
Date: Sun, 14 Jun 2026 14:13:45 +0000
Subject: object/store/packed, cmd/idx-bloom: NewBuilder wants a PackHash

---
 cmd/idx-bloom/main.go                           |  2 +-
 object/store/packed/internal/ingest/finalize.go |  9 +++++----
 object/store/packed/pack.go                     | 10 ++++++++--
 3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/cmd/idx-bloom/main.go b/cmd/idx-bloom/main.go
index 62fb347b..fa471237 100644
--- a/cmd/idx-bloom/main.go
+++ b/cmd/idx-bloom/main.go
@@ -86,7 +86,7 @@ func buildFilter(objectFormat id.ObjectFormat, index *packidx.Packidx) ([]byte,
 		return nil, fmt.Errorf("choosing parameters: %w", err)
 	}
 
-	builder, err := bloom.NewBuilder(objectFormat, bucketCount, k)
+	builder, err := bloom.NewBuilder(objectFormat, bucketCount, k, index.PackHash())
 	if err != nil {
 		return nil, fmt.Errorf("creating builder: %w", err)
 	}
diff --git a/object/store/packed/internal/ingest/finalize.go b/object/store/packed/internal/ingest/finalize.go
index 8caf6b2f..afed996c 100644
--- a/object/store/packed/internal/ingest/finalize.go
+++ b/object/store/packed/internal/ingest/finalize.go
@@ -39,7 +39,7 @@ func (ingestion *ingestion) finalize() (Result, error) {
 		return Result{}, err
 	}
 
-	bloomBuilder, err := ingestion.buildBloom(entries)
+	bloomBuilder, err := ingestion.buildBloom(entries, packHash)
 	if err != nil {
 		return Result{}, err
 	}
@@ -97,14 +97,15 @@ func (ingestion *ingestion) finalize() (Result, error) {
 	}, nil
 }
 
-// buildBloom builds a Bloom filter over the index entries' object IDs.
-func (ingestion *ingestion) buildBloom(entries []packidx.Entry) (*bloom.Builder, error) {
+// buildBloom builds a Bloom filter over the index entries' object IDs,
+// bound to packHash.
+func (ingestion *ingestion) buildBloom(entries []packidx.Entry, packHash []byte) (*bloom.Builder, error) {
 	bucketCount, k, err := bloom.RecommendParams(ingestion.objectFormat, len(entries))
 	if err != nil {
 		return nil, fmt.Errorf("object/store/packed/internal/ingest: %w", err)
 	}
 
-	builder, err := bloom.NewBuilder(ingestion.objectFormat, bucketCount, k)
+	builder, err := bloom.NewBuilder(ingestion.objectFormat, bucketCount, k, packHash)
 	if err != nil {
 		return nil, fmt.Errorf("object/store/packed/internal/ingest: %w", err)
 	}
diff --git a/object/store/packed/pack.go b/object/store/packed/pack.go
index ba865e51..9cd6162b 100644
--- a/object/store/packed/pack.go
+++ b/object/store/packed/pack.go
@@ -73,7 +73,7 @@ func openPack(root *os.Root, name string, objectFormat id.ObjectFormat) (*pack,
 		return nil, fmt.Errorf("%w: pack %q: %w", ErrMalformedPackedStore, name, err)
 	}
 
-	bloomMapping, filter := openBloom(root, name, objectFormat)
+	bloomMapping, filter := openBloom(root, name, objectFormat, idx.PackHash())
 
 	return &pack{
 		name:         name,
@@ -86,7 +86,7 @@ func openPack(root *os.Root, name string, objectFormat id.ObjectFormat) (*pack,
 	}, nil
 }
 
-func openBloom(root *os.Root, name string, objectFormat id.ObjectFormat) (*mmap.Mmap, *bloom.Bloom) {
+func openBloom(root *os.Root, name string, objectFormat id.ObjectFormat, packHash []byte) (*mmap.Mmap, *bloom.Bloom) {
 	mapping, err := mapFile(root, name+".bloom")
 	if err != nil {
 		return nil, nil
@@ -99,6 +99,12 @@ func openBloom(root *os.Root, name string, objectFormat id.ObjectFormat) (*mmap.
 		return nil, nil
 	}
 
+	if !bytes.Equal(filter.PackHash(), packHash) {
+		_ = mapping.Close()
+
+		return nil, nil
+	}
+
 	return mapping, &filter
 }
 
-- 
cgit v1.3.1-10-gc9f91