feat: [presto][iceberg] Add PUFFIN file format support for deletion vector discovery (#27393)

Summary:

Iceberg V3 introduces deletion vectors stored as blobs inside Puffin files.
Previously, the coordinator's IcebergSplitSource rejected PUFFIN-format delete
files with a NOT_SUPPORTED error, preventing V3 deletion vectors from being
discovered and sent to workers.

This diff:
1. Adds PUFFIN to the FileFormat enum (both presto-trunk and
   presto-facebook-trunk) so fromIcebergFileFormat() can convert
   Iceberg's PUFFIN format to Presto's FileFormat.PUFFIN.
2. Removes the PUFFIN rejection check in presto-trunk's
   IcebergSplitSource.toIcebergSplit(), allowing deletion vector
   files to flow through to workers.
3. Updates TestIcebergV3 to verify PUFFIN files are accepted rather
   than rejected at split enumeration time.

The C++ worker-side changes (protocol enum + connector conversion) will
follow in a separate diff.

Differential Revision: D97531557

Author: apurva-meta

presto-iceberg/src/main/java/com/facebook/presto/iceberg/FileFormat.java

@@ -26,7 +26,8 @@ public enum FileFormat
     ORC("orc", true),
     PARQUET("parquet", true),
     AVRO("avro", true),
-    METADATA("metadata.json", false);
+    METADATA("metadata.json", false),
+    PUFFIN("puffin", false);
 
     private final String ext;
     private final boolean splittable;
@@ -61,6 +62,9 @@ public static FileFormat fromIcebergFileFormat(org.apache.iceberg.FileFormat for
             case METADATA:
                 prestoFileFormat = METADATA;
                 break;
+            case PUFFIN:
+                prestoFileFormat = PUFFIN;
+                break;
             default:
                 throw new PrestoException(NOT_SUPPORTED, "Unsupported file format: " + format);
         }

presto-iceberg/src/main/java/com/facebook/presto/iceberg/IcebergSplitSource.java

@@ -18,7 +18,6 @@
 import com.facebook.presto.spi.ConnectorSession;
 import com.facebook.presto.spi.ConnectorSplit;
 import com.facebook.presto.spi.ConnectorSplitSource;
-import com.facebook.presto.spi.PrestoException;
 import com.facebook.presto.spi.SplitWeight;
 import com.facebook.presto.spi.connector.ConnectorPartitionHandle;
 import com.facebook.presto.spi.schedule.NodeSelectionStrategy;
@@ -47,7 +46,6 @@
 import static com.facebook.presto.iceberg.IcebergUtil.getTargetSplitSize;
 import static com.facebook.presto.iceberg.IcebergUtil.metadataColumnsMatchPredicates;
 import static com.facebook.presto.iceberg.IcebergUtil.partitionDataFromStructLike;
-import static com.facebook.presto.spi.StandardErrorCode.NOT_SUPPORTED;
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.common.collect.Iterators.limit;
 import static java.util.Objects.requireNonNull;
@@ -126,13 +124,6 @@ private ConnectorSplit toIcebergSplit(FileScanTask task)
         PartitionSpec spec = task.spec();
         Optional<PartitionData> partitionData = partitionDataFromStructLike(spec, task.file().partition());
 
-        // Validate no PUFFIN deletion vectors (Iceberg v3 feature not yet supported)
-        for (org.apache.iceberg.DeleteFile deleteFile : task.deletes()) {
-            if (deleteFile.format() == org.apache.iceberg.FileFormat.PUFFIN) {
-                throw new PrestoException(NOT_SUPPORTED, "Iceberg deletion vectors (PUFFIN format) are not supported");
-            }
-        }
-
         // TODO: We should leverage residual expression and convert that to TupleDomain.
         //       The predicate here is used by readers for predicate push down at reader level,
         //       so when we do not use residual expression, we are just wasting CPU cycles

presto-iceberg/src/test/java/com/facebook/presto/iceberg/TestIcebergV3.java

@@ -44,6 +44,7 @@
 import static java.lang.String.format;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertFalse;
 
 public class TestIcebergV3
         extends AbstractTestQueryFramework
@@ -279,10 +280,10 @@ public void testOptimizeOnV3Table()
     }
 
     @Test
-    public void testPuffinDeletionVectorsNotSupported()
+    public void testPuffinDeletionVectorsAccepted()
             throws Exception
     {
-        String tableName = "test_puffin_deletion_vectors_not_supported";
+        String tableName = "test_puffin_deletion_vectors_accepted";
         try {
             assertUpdate("CREATE TABLE " + tableName + " (id integer, value varchar) WITH (\"format-version\" = '3')");
             assertUpdate("INSERT INTO " + tableName + " VALUES (1, 'one'), (2, 'two')", 2);
@@ -309,7 +310,20 @@ public void testPuffinDeletionVectorsNotSupported()
                         .commit();
             }
 
-            assertQueryFails("SELECT * FROM " + tableName, "Iceberg deletion vectors.*PUFFIN.*not supported");
+            // The PUFFIN delete file is now accepted by the split source (no longer
+            // throws NOT_SUPPORTED). The query will fail downstream because the fake
+            // .puffin file doesn't exist on disk, but the important thing is that the
+            // coordinator no longer rejects it at split enumeration time.
+            try {
+                computeActual("SELECT * FROM " + tableName);
+            }
+            catch (RuntimeException e) {
+                // Verify the error is NOT the old "PUFFIN not supported" rejection.
+                // Other failures (e.g., fake .puffin file not on disk) are acceptable.
+                assertFalse(
+                        e.getMessage().contains("Iceberg deletion vectors") && e.getMessage().contains("not supported"),
+                        "PUFFIN deletion vectors should be accepted, not rejected: " + e.getMessage());
+            }
         }
         finally {
             dropTable(tableName);