From 686c5f1176a35fa0a0ea8aacb86be2b327381bb3 Mon Sep 17 00:00:00 2001
From: Noritaka Sekiyama <noritaka.sekiyama@databricks.com>
Date: Wed, 10 Jun 2026 12:41:22 +0900
Subject: [PATCH] Add Spark interop test for reading Puffin deletion vectors

---
 .../integration/test_puffin_spark_interop.py  | 93 +++++++++++++++++++
 1 file changed, 93 insertions(+)
 create mode 100644 tests/integration/test_puffin_spark_interop.py

diff --git a/tests/integration/test_puffin_spark_interop.py b/tests/integration/test_puffin_spark_interop.py
new file mode 100644
index 0000000000..d4c6735fca
--- /dev/null
+++ b/tests/integration/test_puffin_spark_interop.py
@@ -0,0 +1,93 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+import pytest
+from pyspark.sql import SparkSession
+
+from pyiceberg.catalog.rest import RestCatalog
+from pyiceberg.manifest import ManifestContent
+from pyiceberg.table.puffin import PuffinFile
+
+
+def run_spark_commands(spark: SparkSession, sqls: list[str]) -> None:
+    for sql in sqls:
+        spark.sql(sql)
+
+
+@pytest.mark.integration
+def test_read_spark_written_puffin_dv(spark: SparkSession, session_catalog: RestCatalog) -> None:
+    """Verify pyiceberg can read Puffin DVs written by Spark."""
+    identifier = "default.spark_puffin_format_test"
+
+    run_spark_commands(spark, [f"DROP TABLE IF EXISTS {identifier}"])
+    run_spark_commands(
+        spark,
+        [
+            f"""
+            CREATE TABLE {identifier} (id BIGINT)
+            USING iceberg
+            TBLPROPERTIES (
+                'format-version' = '3',
+                'write.delete.mode' = 'merge-on-read'
+            )
+            """,
+        ],
+    )
+
+    df = spark.range(1, 51)
+    df.coalesce(1).writeTo(identifier).append()
+
+    files_before = spark.sql(f"SELECT * FROM {identifier}.files").collect()
+    assert len(files_before) == 1, f"Expected 1 file, got {len(files_before)}"
+
+    run_spark_commands(spark, [f"DELETE FROM {identifier} WHERE id IN (10, 20, 30, 40)"])
+
+    table = session_catalog.load_table(identifier)
+    current_snapshot = table.current_snapshot()
+    assert current_snapshot is not None
+
+    manifests = current_snapshot.manifests(table.io)
+    delete_manifests = [m for m in manifests if m.content == ManifestContent.DELETES]
+    assert len(delete_manifests) > 0, "Expected delete manifest with DVs"
+
+    delete_manifest = delete_manifests[0]
+    entries = list(delete_manifest.fetch_manifest_entry(table.io))
+    assert len(entries) > 0, "Expected at least one delete file entry"
+
+    delete_entry = entries[0]
+    puffin_path = delete_entry.data_file.file_path
+    assert puffin_path.endswith(".puffin"), f"Expected Puffin file, got: {puffin_path}"
+
+    input_file = table.io.new_input(puffin_path)
+    with input_file.open() as f:
+        puffin_bytes = f.read()
+
+    puffin = PuffinFile(puffin_bytes)
+
+    assert len(puffin.footer.blobs) == 1, "Expected exactly one blob"
+
+    blob = puffin.footer.blobs[0]
+    assert blob.type == "deletion-vector-v1"
+    assert "referenced-data-file" in blob.properties
+    assert blob.properties["cardinality"] == "4"
+
+    dv_dict = puffin.to_vector()
+    assert len(dv_dict) == 1, "Expected one data file's deletions"
+
+    for _data_file_path, chunked_array in dv_dict.items():
+        positions = chunked_array.to_pylist()
+        assert len(positions) == 4, f"Expected 4 deleted positions, got {len(positions)}"
+        assert sorted(positions) == [9, 19, 29, 39], f"Unexpected positions: {positions}"