Bug 1886709 part 2: Implement the UIA Invoke pattern. r=nlapre

Differential Revision: https://phabricator.services.mozilla.com/D205432

accessible/tests/browser/windows/uia/browser.toml

@@ -13,4 +13,6 @@ support-files = ["head.js"]
 ["browser_focus.js"]
 ["browser_generalProps.js"]
 
+["browser_simplePatterns.js"]
+
 ["browser_tree.js"]

accessible/tests/browser/windows/uia/browser_simplePatterns.js

@@ -0,0 +1,41 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+/**
+ * Test the Invoke pattern.
+ */
+addUiaTask(
+  `
+<button id="button">button</button>
+<p id="p">p</p>
+  `,
+  async function testInvoke() {
+    await definePyVar("doc", `getDocUia()`);
+    await assignPyVarToUiaWithId("button");
+    await definePyVar("pattern", `getUiaPattern(button, "Invoke")`);
+    ok(await runPython(`bool(pattern)`), "button has Invoke pattern");
+    info("Calling Invoke on button");
+    // The button will get focus when it is clicked.
+    let focused = waitForEvent(EVENT_FOCUS, "button");
+    // The UIA -> IA2 proxy doesn't fire the Invoked event.
+    if (gIsUiaEnabled) {
+      await setUpWaitForUiaEvent("Invoke_Invoked", "button");
+    }
+    await runPython(`pattern.Invoke()`);
+    await focused;
+    ok(true, "button got focus");
+    if (gIsUiaEnabled) {
+      await waitForUiaEvent();
+      ok(true, "button got Invoked event");
+    }
+
+    let hasPattern = await runPython(`
+      p = findUiaByDomId(doc, "p")
+      return bool(getUiaPattern(p, "Invoke"))
+    `);
+    ok(!hasPattern, "p doesn't have Invoke pattern");
+  }
+);

accessible/windows/msaa/MsaaAccessible.h

@@ -146,6 +146,10 @@ class MsaaAccessible : public ia2Accessible,
                                            EXCEPINFO* pExcepInfo,
                                            UINT* puArgErr) override;
 
+  // UIA's IInvokeProvider has a method called Invoke too, but it's fine because
+  // it accepts very different parameters.
+  using uiaRawElmProvider::Invoke;
+
  protected:
   explicit MsaaAccessible(Accessible* aAcc);
   virtual ~MsaaAccessible();

accessible/windows/uia/uiaRawElmProvider.cpp

@@ -73,6 +73,8 @@ uiaRawElmProvider::QueryInterface(REFIID aIid, void** aInterface) {
     *aInterface = static_cast<IRawElementProviderSimple*>(this);
   } else if (aIid == IID_IRawElementProviderFragment) {
     *aInterface = static_cast<IRawElementProviderFragment*>(this);
+  } else if (aIid == IID_IInvokeProvider) {
+    *aInterface = static_cast<IInvokeProvider*>(this);
   } else {
     return E_NOINTERFACE;
   }
@@ -164,8 +166,19 @@ STDMETHODIMP
 uiaRawElmProvider::GetPatternProvider(
     PATTERNID aPatternId, __RPC__deref_out_opt IUnknown** aPatternProvider) {
   if (!aPatternProvider) return E_INVALIDARG;
-
   *aPatternProvider = nullptr;
+  Accessible* acc = Acc();
+  if (!acc) {
+    return CO_E_OBJNOTCONNECTED;
+  }
+  switch (aPatternId) {
+    case UIA_InvokePatternId:
+      if (acc->ActionCount() > 0) {
+        RefPtr<IInvokeProvider> invoke = this;
+        invoke.forget(aPatternProvider);
+      }
+      return S_OK;
+  }
   return S_OK;
 }
 
@@ -453,6 +466,23 @@ uiaRawElmProvider::get_FragmentRoot(
   return S_OK;
 }
 
+// IInvokeProvider methods
+
+STDMETHODIMP
+uiaRawElmProvider::Invoke() {
+  Accessible* acc = Acc();
+  if (!acc) {
+    return CO_E_OBJNOTCONNECTED;
+  }
+  if (acc->DoAction(0)) {
+    // We don't currently have a way to notify when the action was actually
+    // handled. The UIA documentation says it's okay to fire this immediately if
+    // it "is not possible or practical to wait until the action is complete".
+    ::UiaRaiseAutomationEvent(this, UIA_Invoke_InvokedEventId);
+  }
+  return S_OK;
+}
+
 // Private methods
 
 bool uiaRawElmProvider::IsControl() {

accessible/windows/uia/uiaRawElmProvider.h

@@ -21,7 +21,8 @@ class Accessible;
  */
 class uiaRawElmProvider : public IAccessibleEx,
                           public IRawElementProviderSimple,
-                          public IRawElementProviderFragment {
+                          public IRawElementProviderFragment,
+                          public IInvokeProvider {
  public:
   static void RaiseUiaEventForGeckoEvent(Accessible* aAcc,
                                          uint32_t aGeckoEvent);
@@ -81,6 +82,9 @@ class uiaRawElmProvider : public IAccessibleEx,
       /* [retval][out] */ __RPC__deref_out_opt IRawElementProviderFragmentRoot**
           aRetVal);
 
+  // IInvokeProvider
+  virtual HRESULT STDMETHODCALLTYPE Invoke(void);
+
  private:
   Accessible* Acc() const;
   bool IsControl();