Properly honor the async option (or lack thereof) in iteration to maintain back-compat for sync iteration

Author: kriszyp

resources/Table.ts

@@ -2239,11 +2239,12 @@ export function makeTable(options) {
 				entries = transformToEntries(entries, select, context, readTxn, null);
 				let ordered;
 				// if we are doing post-ordering, we need to get records first, then sort them
-				results.iterate = function () {
+				results.iterate = function (options: { async: boolean }) {
 					let sortedArrayIterator: IterableIterator<any>;
-					const dbIterator = entries[Symbol.asyncIterator]
-						? entries[Symbol.asyncIterator]()
-						: entries[Symbol.iterator]();
+					const dbIterator =
+						options?.async && entries[Symbol.asyncIterator]
+							? entries[Symbol.asyncIterator]()
+							: entries[Symbol.iterator]();
 					let dbDone: boolean;
 					const dbOrderedAttribute = sort.dbOrderedAttribute;
 					let enqueuedEntryForNextGroup: any;
@@ -2357,7 +2358,10 @@ export function makeTable(options) {
 				};
 				applySortingOnSelect(sort);
 			} else {
-				results.iterate = (entries[Symbol.asyncIterator] || entries[Symbol.iterator]).bind(entries);
+				results.iterate = (options: { async: boolean }) => {
+					if (options?.async && entries[Symbol.asyncIterator]) return entries[Symbol.asyncIterator]();
+					else return entries[Symbol.iterator]();
+				};
 				results = results.map(function (entry) {
 					try {
 						// because this is a part of a stream of results, we will often be continuing to iterate over the results when there are errors,

unitTests/resources/query.test.js

@@ -199,6 +199,20 @@ describe('Querying through Resource API', () => {
 		}
 		assert.equal(results.length, 1);
 	});
+	it('Ensure that we are yielding when querying data in a table', async function () {
+		let results = [];
+		let yielded = false;
+		setImmediate(() => {
+			yielded = true;
+		});
+		for await (let record of QueryTable.search({
+			conditions: [{ attribute: 'id', comparator: 'less_than_equal', value: 'id-3' }],
+		})) {
+			results.push(record);
+		}
+		assert(yielded);
+		assert.equal(results.length, 24);
+	});
 	it('Query data in a table with non-indexed property', async function () {
 		let results = [];
 		for await (let record of QueryTable.search({
@@ -342,7 +356,8 @@ describe('Querying through Resource API', () => {
 
 		it('Query relational data in a table with many-to-one', async function () {
 			let results = [];
-			for await (let record of QueryTable.search({
+			// do this test with sync iteration to verify it is possible
+			for (let record of QueryTable.search({
 				conditions: [{ attribute: 'id', value: 'id-1' }],
 				select: ['id', 'related', 'name'],
 			})) {