Added AlterTableTest using InMemoryCatalog.

Author: subkanthi

ice/src/test/java/com/altinity/ice/cli/internal/cmd/AlterTableTest.java

@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2025 Altinity Inc and/or its affiliates. All rights reserved.
+ *
+ * Licensed 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
+ */
+package com.altinity.ice.cli.internal.cmd;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+import java.util.Arrays;
+import java.util.List;
+import org.apache.iceberg.PartitionSpec;
+import org.apache.iceberg.Schema;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.catalog.TableIdentifier;
+import org.apache.iceberg.inmemory.InMemoryCatalog;
+import org.apache.iceberg.types.Types;
+import org.testng.annotations.BeforeMethod;
+import org.testng.annotations.Test;
+
+public class AlterTableTest {
+
+  private InMemoryCatalog catalog;
+  private TableIdentifier tableId;
+  private Schema schema;
+
+  @BeforeMethod
+  public void setUp() {
+    catalog = new InMemoryCatalog();
+    catalog.initialize("test-catalog", java.util.Map.of());
+    tableId = TableIdentifier.of("test", "table1");
+
+    // create namespace.
+    catalog.createNamespace(org.apache.iceberg.catalog.Namespace.of("test"));
+    schema =
+        new Schema(
+            Types.NestedField.required(1, "id", Types.LongType.get()),
+            Types.NestedField.required(2, "name", Types.StringType.get()),
+            Types.NestedField.required(3, "timestamp_col", Types.TimestampType.withZone()),
+            Types.NestedField.required(4, "date_col", Types.DateType.get()));
+  }
+
+  @Test
+  public void testDropPartitionField() throws Exception {
+    PartitionSpec partitionSpec =
+        PartitionSpec.builderFor(schema).identity("name").year("timestamp_col").build();
+
+    Table table = catalog.buildTable(tableId, schema).withPartitionSpec(partitionSpec).create();
+
+    assertThat(table.spec().fields()).hasSize(2);
+    assertThat(table.spec().fields().get(0).name()).isEqualTo("name");
+    assertThat(table.spec().fields().get(1).name()).isEqualTo("timestamp_col_year");
+
+    List<AlterTable.Update> updates = Arrays.asList(new AlterTable.DropPartitionField("name"));
+
+    AlterTable.run(catalog, tableId, updates);
+
+    table = catalog.loadTable(tableId);
+    assertThat(table.spec().fields()).hasSize(1);
+    assertThat(table.spec().fields().get(0).name()).isEqualTo("timestamp_col_year");
+  }
+
+  @Test
+  public void testDropPartitionFieldByTransformName() throws Exception {
+    PartitionSpec partitionSpec =
+        PartitionSpec.builderFor(schema).identity("name").year("timestamp_col").build();
+
+    Table table = catalog.buildTable(tableId, schema).withPartitionSpec(partitionSpec).create();
+
+    assertThat(table.spec().fields()).hasSize(2);
+
+    List<AlterTable.Update> updates =
+        Arrays.asList(new AlterTable.DropPartitionField("timestamp_col_year"));
+
+    AlterTable.run(catalog, tableId, updates);
+
+    table = catalog.loadTable(tableId);
+    assertThat(table.spec().fields()).hasSize(1);
+    assertThat(table.spec().fields().get(0).name()).isEqualTo("name");
+  }
+
+  @Test
+  public void testDropNonExistentPartitionField() throws Exception {
+    PartitionSpec partitionSpec = PartitionSpec.builderFor(schema).identity("name").build();
+
+    catalog.buildTable(tableId, schema).withPartitionSpec(partitionSpec).create();
+
+    List<AlterTable.Update> updates =
+        Arrays.asList(new AlterTable.DropPartitionField("non_existent_field"));
+
+    assertThatThrownBy(() -> AlterTable.run(catalog, tableId, updates))
+        .isInstanceOf(IllegalArgumentException.class);
+  }
+
+  @Test
+  public void testDropAllPartitionFields() throws Exception {
+    PartitionSpec partitionSpec =
+        PartitionSpec.builderFor(schema).identity("name").year("timestamp_col").build();
+
+    Table table = catalog.buildTable(tableId, schema).withPartitionSpec(partitionSpec).create();
+
+    assertThat(table.spec().fields()).hasSize(2);
+
+    List<AlterTable.Update> updates =
+        Arrays.asList(
+            new AlterTable.DropPartitionField("name"),
+            new AlterTable.DropPartitionField("timestamp_col_year"));
+
+    AlterTable.run(catalog, tableId, updates);
+
+    table = catalog.loadTable(tableId);
+    assertThat(table.spec().fields()).isEmpty();
+  }
+}