test: Add DuckDB arrow scan compatibility tests.

Author: jheer

test/duckdb-compat-test.js

@@ -0,0 +1,43 @@
+import assert from 'node:assert';
+import { DuckDB } from '@uwdata/mosaic-duckdb';
+import { tableFromArrays, tableFromIPC, tableToIPC } from '../src/index.js';
+import * as dataMethods from './util/data.js';
+
+// Arrow types not supported by DuckDB
+const skip = new Set([
+  'binaryView', 'empty', 'largeListView', 'listView',
+  'runEndEncoded32', 'runEndEncoded64', 'utf8View'
+]);
+
+describe('DuckDB compatibility', () => {
+  for (const [name, method] of Object.entries(dataMethods)) {
+    if (skip.has(name)) continue;
+    it(`includes ${name} data`, async () => {
+      const data = await method();
+      const load = await Promise.all(
+        data.map(({ bytes }) => loadIPC(tableFromIPC(bytes)))
+      );
+      assert.deepStrictEqual(load, Array(data.length).fill(true));
+    });
+  }
+
+  it('includes default dictionary types', async () => {
+    const t = tableFromArrays({ foo: ['x', 'y', 'z'] });
+    assert.strictEqual(await loadIPC(t), true);
+  });
+});
+
+function loadIPC(table) {
+  const bytes = tableToIPC(table, { format: 'stream' });
+  return new Promise((resolve) => {
+    const db = new DuckDB();
+    db.db.register_buffer('arrow_ipc', [bytes], true, (err) => {
+      if (err) {
+        console.error(err);
+        resolve(false);
+      } else {
+        resolve(true);
+      }
+    });
+  });
+}