GH-43118: [JS] Add interval for unit MONTH_DAY_NANO

dev/archery/archery/integration/datagen.py

@@ -1887,11 +1887,9 @@ def _temp_path():
 
         generate_duration_case(),
 
-        generate_interval_case()
-        .skip_tester('JS'),
+        generate_interval_case(),
 
-        generate_month_day_nano_interval_case()
-        .skip_tester('JS'),
+        generate_month_day_nano_interval_case(),
 
         generate_map_case(),
 

js/src/util/interval.ts

@@ -0,0 +1,58 @@
+// 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.
+
+type EncodedIntervalMonthDayNano = {
+    months: number;
+    days: number;
+    nanoseconds: bigint | number;
+};
+
+type EncodedIntervalDayTime = {
+    days: number;
+    milliseconds: number;
+};
+
+export function encodeIntervalDayTime(intervalArray: EncodedIntervalDayTime[]) {
+    const length = intervalArray.length;
+    const data = new Int32Array(length * 2);
+    const intervalLength = intervalArray.length;
+    for (let i = 0, ptr = 0; i < intervalLength; i++) {
+        const interval = intervalArray[i];
+        data[ptr++] = interval.days ?? 0;
+        data[ptr++] = interval.milliseconds ?? 0;
+    }
+    return data;
+}
+
+export function encodeIntervalMonthDayNano(
+    intervalArray: EncodedIntervalMonthDayNano[]
+) {
+    const length = intervalArray.length;
+    const data = new Int32Array(length * 4);
+    const intervalLength = intervalArray.length;
+    for (let i = 0, ptr = 0; i < intervalLength; i++) {
+        const interval = intervalArray[i];
+        const nanoseconds = new Int32Array(
+            new BigInt64Array([BigInt(interval.nanoseconds ?? 0)]).buffer
+        );
+        data[ptr++] = interval.months ?? 0;
+        data[ptr++] = interval.days ?? 0;
+        data[ptr++] = nanoseconds[0];
+        data[ptr++] = nanoseconds[1];
+    }
+    return data;
+}

js/src/visitor/vectorloader.ts

@@ -24,9 +24,10 @@ import { Visitor } from '../visitor.js';
 import { packBools } from '../util/bit.js';
 import { encodeUtf8 } from '../util/utf8.js';
 import { Int64, Int128 } from '../util/int.js';
-import { UnionMode, DateUnit, MetadataVersion } from '../enum.js';
+import { UnionMode, DateUnit, MetadataVersion, IntervalUnit } from '../enum.js';
 import { toArrayBufferView } from '../util/buffer.js';
 import { BufferRegion, FieldNode } from '../ipc/metadata/message.js';
+import { encodeIntervalDayTime, encodeIntervalMonthDayNano } from '../util/interval.js';
 
 /** @ignore */
 export interface VectorLoader extends Visitor {
@@ -178,6 +179,13 @@ export class JSONVectorLoader extends VectorLoader {
             return packBools(sources[offset] as number[]);
         } else if (DataType.isUtf8(type) || DataType.isLargeUtf8(type)) {
             return encodeUtf8((sources[offset] as string[]).join(''));
+        } else if (DataType.isInterval(type)) {
+            if (type.unit === IntervalUnit.MONTH_DAY_NANO) {
+                return encodeIntervalMonthDayNano(sources[offset]);
+            }
+            if (type.unit === IntervalUnit.DAY_TIME) {
+                return encodeIntervalDayTime(sources[offset]);
+            }
         }
         return toArrayBufferView(Uint8Array, toArrayBufferView(type.ArrayType, sources[offset].map((x) => +x)));
     }