Dispatch the combobox input event so onInput works

src/ui-kit/experimental/aria/abstract-combobox/abstract-combobox.spec.ts

@@ -0,0 +1,66 @@
+import { AbstractCombobox } from "./abstract-combobox";
+
+// A popup stands in for AbstractPopup: the combobox only needs the three
+// members its constructor and event wiring touch.
+function popupStub() {
+  const cell = {
+    node: { id: "cell-1" },
+    addToTabOrder: () => {},
+    removeFromTabOrder: () => {},
+  };
+  return {
+    node: { id: "popup-1" },
+    focused: cell,
+    getSelected: () => cell,
+    onClick: (_callback: Function, _context: Object) => {},
+    onKeydown: (_callback: Function, _context: Object) => {},
+  };
+}
+
+describe("The AbstractCombobox", () => {
+  let input: HTMLInputElement;
+  let combobox: AbstractCombobox;
+
+  beforeEach(() => {
+    input = document.createElement("input");
+    input.id = "combobox-input";
+    document.body.appendChild(input);
+    combobox = new AbstractCombobox(input, popupStub() as any);
+  });
+
+  afterEach(() => {
+    input.remove();
+  });
+
+  it("should call an onInput callback when the input changes", () => {
+    // onInput() is public and "input" is a registered event, but nothing used
+    // to dispatch it, so callbacks registered here were never invoked.
+    let calls = 0;
+    combobox.onInput(() => calls++, {});
+
+    input.value = "abc";
+    input.dispatchEvent(new Event("input"));
+
+    expect(calls).toBe(1);
+  });
+
+  it("should still call an onSearch callback when the input changes", () => {
+    let calls = 0;
+    combobox.onSearch(() => calls++, {});
+
+    input.value = "abc";
+    input.dispatchEvent(new Event("input"));
+
+    expect(calls).toBe(1);
+  });
+
+  it("should pass the input event through to both callbacks", () => {
+    const seen: string[] = [];
+    combobox.onInput((e: Event) => seen.push(`input:${e.type}`), {});
+    combobox.onSearch((e: Event) => seen.push(`search:${e.type}`), {});
+
+    input.dispatchEvent(new Event("input"));
+
+    expect(seen).toEqual(["input:input", "search:input"]);
+  });
+});

src/ui-kit/experimental/aria/abstract-combobox/abstract-combobox.ts

@@ -65,6 +65,10 @@ export class AbstractCombobox {
 
   private _setupInputEvents(): void {
     this._input.addEventListener("input", (e) => {
+      // "input" is declared in _initEventDispatcher and exposed by onInput(),
+      // so it has to be dispatched here as well; only "search" used to be, which
+      // left onInput() registering callbacks that were never called.
+      this._dispatcher.dispatch("input", e);
       this._dispatcher.dispatch("search", e);
     });