Add an assertion when updating conversations; update cleanData

ts/test-both/util/isIterable_test.ts

@@ -0,0 +1,50 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { assert } from 'chai';
+
+import { isIterable } from '../../util/isIterable';
+
+describe('isIterable', () => {
+  it('returns false for non-iterables', () => {
+    assert.isFalse(isIterable(undefined));
+    assert.isFalse(isIterable(null));
+    assert.isFalse(isIterable(123));
+    assert.isFalse(isIterable({ foo: 'bar' }));
+    assert.isFalse(
+      isIterable({
+        length: 2,
+        '0': 'fake',
+        '1': 'array',
+      })
+    );
+  });
+
+  it('returns true for iterables', () => {
+    assert.isTrue(isIterable('strings are iterable'));
+    assert.isTrue(isIterable(['arrays too']));
+    assert.isTrue(isIterable(new Set('and sets')));
+    assert.isTrue(isIterable(new Map([['and', 'maps']])));
+    assert.isTrue(
+      isIterable({
+        [Symbol.iterator]() {
+          return {
+            next() {
+              return {
+                value: 'endless iterable',
+                done: false,
+              };
+            },
+          };
+        },
+      })
+    );
+    assert.isTrue(
+      isIterable(
+        (function* generators() {
+          yield 123;
+        })()
+      )
+    );
+  });
+});