feat: Variant Support

crates/catalog/glue/src/schema.rs

@@ -182,6 +182,10 @@ impl SchemaVisitor for GlueSchemaBuilder {
 
         Ok(glue_type)
     }
+
+    fn variant(&mut self, _v: &iceberg::spec::VariantType) -> Result<Self::T> {
+        Ok("variant".to_string())
+    }
 }
 
 #[cfg(test)]

crates/catalog/hms/src/schema.rs

@@ -139,6 +139,10 @@ impl SchemaVisitor for HiveSchemaBuilder {
 
         Ok(hive_type)
     }
+
+    fn variant(&mut self, _v: &iceberg::spec::VariantType) -> Result<Self::T> {
+        Ok("variant".to_string())
+    }
 }
 
 #[cfg(test)]

crates/iceberg/src/arrow/caching_delete_file_loader.rs

@@ -34,7 +34,7 @@ use crate::io::FileIO;
 use crate::scan::{ArrowRecordBatchStream, FileScanTaskDeleteFile};
 use crate::spec::{
     DataContentType, Datum, ListType, MapType, NestedField, NestedFieldRef, PartnerAccessor,
-    PrimitiveType, Schema, SchemaRef, SchemaWithPartnerVisitor, StructType, Type,
+    PrimitiveType, Schema, SchemaRef, SchemaWithPartnerVisitor, StructType, Type, VariantType,
     visit_schema_with_partner,
 };
 use crate::{Error, ErrorKind, Result};
@@ -537,6 +537,10 @@ impl SchemaWithPartnerVisitor<ArrayRef> for EqDelColumnProcessor<'_> {
     fn primitive(&mut self, _primitive: &PrimitiveType, _partner: &ArrayRef) -> Result<()> {
         Ok(())
     }
+
+    fn variant(&mut self, _v: &VariantType, _partner: &ArrayRef) -> Result<()> {
+        Ok(())
+    }
 }
 
 struct EqDelRecordBatchPartnerAccessor;

crates/iceberg/src/arrow/nan_val_cnt_visitor.rs

@@ -28,7 +28,7 @@ use crate::Result;
 use crate::arrow::{ArrowArrayAccessor, FieldMatchMode};
 use crate::spec::{
     ListType, MapType, NestedFieldRef, PrimitiveType, Schema, SchemaRef, SchemaWithPartnerVisitor,
-    StructType, visit_struct_with_partner,
+    StructType, VariantType, visit_struct_with_partner,
 };
 
 macro_rules! cast_and_update_cnt_map {
@@ -122,6 +122,10 @@ impl SchemaWithPartnerVisitor<ArrayRef> for NanValueCountVisitor {
         Ok(())
     }
 
+    fn variant(&mut self, _v: &VariantType, _col: &ArrayRef) -> Result<Self::T> {
+        Ok(())
+    }
+
     fn after_struct_field(&mut self, field: &NestedFieldRef, partner: &ArrayRef) -> Result<()> {
         let field_id = field.id;
         count_float_nans!(partner, self, field_id);