From 338877b3cb544b528e98e089d48b0f1851d1a6cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marcos=20C=C3=A1ceres?= <mcaceres@mozilla.com>
Date: Wed, 17 Jun 2020 10:18:41 +0000
Subject: [PATCH] Bug 1643205 - Navigator's share() must consume user
 activation r=edgar

navigator.share() must consume the user activation.

Differential Revision: https://phabricator.services.mozilla.com/D79640
---
 dom/base/Navigator.cpp                        | 24 +++++------
 dom/moz.build                                 |  1 +
 dom/webshare/moz.build                        | 11 +++++
 dom/webshare/test/mochitest/mochitest.ini     |  5 +++
 ...vigator_share_consume_user_activation.html | 43 +++++++++++++++++++
 .../share-consume-activation.https.html       | 33 ++++++++++++++
 .../tests/web-share/share-empty.https.html    | 41 ++++++++++++------
 .../web-share/share-url-invalid.https.html    | 23 ++++++----
 8 files changed, 147 insertions(+), 34 deletions(-)
 create mode 100644 dom/webshare/moz.build
 create mode 100644 dom/webshare/test/mochitest/mochitest.ini
 create mode 100644 dom/webshare/test/mochitest/test_navigator_share_consume_user_activation.html
 create mode 100644 testing/web-platform/tests/web-share/share-consume-activation.https.html

diff --git a/dom/base/Navigator.cpp b/dom/base/Navigator.cpp
index aa3fa6719f05..d8600ea437f4 100644
--- a/dom/base/Navigator.cpp
+++ b/dom/base/Navigator.cpp
@@ -1374,6 +1374,17 @@ Promise* Navigator::Share(const ShareData& aData, ErrorResult& aRv) {
     return nullptr;
   }
 
+  // null checked above
+  auto* doc = mWindow->GetExtantDoc();
+
+  if (StaticPrefs::dom_webshare_requireinteraction() &&
+      !doc->ConsumeTransientUserGestureActivation()) {
+    aRv.ThrowNotAllowedError(
+        "User activation was already consumed "
+        "or share() was not activated by a user gesture.");
+    return nullptr;
+  }
+
   // If none of data's members title, text, or url are present, reject p with
   // TypeError, and abort these steps.
   bool someMemberPassed = aData.mTitle.WasPassed() || aData.mText.WasPassed() ||
@@ -1384,9 +1395,6 @@ Promise* Navigator::Share(const ShareData& aData, ErrorResult& aRv) {
     return nullptr;
   }
 
-  // null checked above
-  auto doc = mWindow->GetExtantDoc();
-
   // If data's url member is present, try to resolve it...
   nsCOMPtr<nsIURI> url;
   if (aData.mUrl.WasPassed()) {
@@ -1415,16 +1423,6 @@ Promise* Navigator::Share(const ShareData& aData, ErrorResult& aRv) {
     text.SetIsVoid(true);
   }
 
-  // The spec does the "triggered by user activation" after the data checks.
-  // Unfortunately, both Chrome and Safari behave this way, so interop wins.
-  // https://github.com/w3c/web-share/pull/118
-  if (StaticPrefs::dom_webshare_requireinteraction() &&
-      !UserActivation::IsHandlingUserInput()) {
-    NS_WARNING("Attempt to share not triggered by user activation");
-    aRv.Throw(NS_ERROR_DOM_NOT_ALLOWED_ERR);
-    return nullptr;
-  }
-
   // Let mSharePromise be a new promise.
   mSharePromise = Promise::Create(mWindow->AsGlobal(), aRv);
   if (aRv.Failed()) {
diff --git a/dom/moz.build b/dom/moz.build
index c4c446fefb69..d34d8a7f7562 100644
--- a/dom/moz.build
+++ b/dom/moz.build
@@ -86,6 +86,7 @@ DIRS += [
     'url',
     'webauthn',
     'webidl',
+    'webshare',
     'xml',
     'xslt',
     'xul',
diff --git a/dom/webshare/moz.build b/dom/webshare/moz.build
new file mode 100644
index 000000000000..42720eb7fde7
--- /dev/null
+++ b/dom/webshare/moz.build
@@ -0,0 +1,11 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+with Files("**"):
+    BUG_COMPONENT = ("Core", "DOM: Core & HTML")
+
+MOCHITEST_MANIFESTS += ['test/mochitest/mochitest.ini']
+
diff --git a/dom/webshare/test/mochitest/mochitest.ini b/dom/webshare/test/mochitest/mochitest.ini
new file mode 100644
index 000000000000..295815d492fa
--- /dev/null
+++ b/dom/webshare/test/mochitest/mochitest.ini
@@ -0,0 +1,5 @@
+[DEFAULT]
+prefs =
+  dom.webshare.enabled=true
+scheme = https
+[test_navigator_share_consume_user_activation.html]
diff --git a/dom/webshare/test/mochitest/test_navigator_share_consume_user_activation.html b/dom/webshare/test/mochitest/test_navigator_share_consume_user_activation.html
new file mode 100644
index 000000000000..9cb3f04d96a6
--- /dev/null
+++ b/dom/webshare/test/mochitest/test_navigator_share_consume_user_activation.html
@@ -0,0 +1,43 @@
+<!DOCTYPE html>
+<title>Web Share: consume transient activation</title>
+<script src="/tests/SimpleTest/SimpleTest.js"></script>
+<script src="/tests/SimpleTest/EventUtils.js"></script>
+<link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+<body>
+  <button id="share">Share</button>
+</body>
+<script>
+  // TODO: add a task that tests share() consume the transient user activation.
+  // Because OS-level prompt can't be cancelled, it's currently not possible to
+  // test this. We need to add a Web share Mocking service:
+  // https://bugzilla.mozilla.org/show_bug.cgi?id=1646229
+
+  // test that share() would be blocked with an already-consumed-activation.
+  add_task(async function blockedIfAlreadyConsumed() {
+    const wrappedDoc = SpecialPowers.wrap(document);
+    const button = document.getElementById("share");
+
+    // Kick off transient activation
+    synthesizeMouseAtCenter(button, {});
+
+    ok(
+      wrappedDoc.hasValidTransientUserGestureActivation,
+      "Activated by a gesture"
+    );
+
+    wrappedDoc.consumeTransientUserGestureActivation();
+
+    try {
+      const sharePromise = navigator.share({ title: "test" });
+      await sharePromise;
+      ok(false, "must throw because activation was already consumed");
+    } catch (err) {
+      is(err.name, "NotAllowedError", "Expected NotAllowedError DOMException");
+    } finally {
+      ok(
+        !wrappedDoc.hasValidTransientUserGestureActivation,
+        "share() must consume the activation"
+      );
+    }
+  });
+</script>
diff --git a/testing/web-platform/tests/web-share/share-consume-activation.https.html b/testing/web-platform/tests/web-share/share-consume-activation.https.html
new file mode 100644
index 000000000000..ba14117c1d95
--- /dev/null
+++ b/testing/web-platform/tests/web-share/share-consume-activation.https.html
@@ -0,0 +1,33 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8" />
+    <title>WebShare Test: consume user activation</title>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="resources/manual-helper.js"></script>
+    <script src="/resources/testdriver-vendor.js"></script>
+    <script src="/resources/testdriver.js"></script>
+  </head>
+  <body>
+    <script>
+      promise_test(async t => {
+        // Not activated by user gesture, so not allowed!
+        await promise_rejects_dom(t, "NotAllowedError", navigator.share());
+
+        await test_driver.bless("web share");
+
+        // We have a gesture, but the URL is invalid - so TypeError!
+        await promise_rejects_js(
+          t,
+          TypeError,
+          navigator.share({ url: "http://example.com:65536" })
+        );
+
+        // The activation has been consumed, so calling share() again would require
+        // a new gesture.
+        await promise_rejects_dom(t, "NotAllowedError", navigator.share());
+      }, "Calling share consumes user activation");
+    </script>
+  </body>
+</html>
diff --git a/testing/web-platform/tests/web-share/share-empty.https.html b/testing/web-platform/tests/web-share/share-empty.https.html
index ce7e2fefbd47..d0e0241ae44e 100644
--- a/testing/web-platform/tests/web-share/share-empty.https.html
+++ b/testing/web-platform/tests/web-share/share-empty.https.html
@@ -1,34 +1,49 @@
 <!DOCTYPE html>
 <html>
   <head>
-    <meta charset="utf-8">
+    <meta charset="utf-8" />
     <title>WebShare Test: Share no known fields</title>
     <script src="/resources/testharness.js"></script>
     <script src="/resources/testharnessreport.js"></script>
     <script src="resources/manual-helper.js"></script>
+    <script src="/resources/testdriver-vendor.js"></script>
+    <script src="/resources/testdriver.js"></script>
   </head>
   <body>
     <script>
-        promise_test(t => {
+      promise_test(async t => {
+        await test_driver.bless("web share", () => {
           return promise_rejects_js(t, TypeError, navigator.share());
-        }, 'share with no arguments (same as empty dictionary)');
+        });
+      }, "share with no arguments (same as empty dictionary)");
 
-        promise_test(t => {
+      promise_test(async t => {
+        await test_driver.bless("web share", () => {
           return promise_rejects_js(t, TypeError, navigator.share({}));
-        }, 'share with an empty dictionary');
+        });
+      }, "share with an empty dictionary");
 
-        promise_test(t => {
+      promise_test(async t => {
+        await test_driver.bless("web share", () => {
           return promise_rejects_js(t, TypeError, navigator.share(undefined));
-        }, 'share with a undefined argument (same as empty dictionary)');
+        });
+      }, "share with a undefined argument (same as empty dictionary)");
 
-        promise_test(t => {
+      promise_test(async t => {
+        await test_driver.bless("web share", () => {
           return promise_rejects_js(t, TypeError, navigator.share(null));
-        }, 'share with a null argument (same as empty dictionary)');
+        });
+      }, "share with a null argument (same as empty dictionary)");
 
-        promise_test(t => {
-          return promise_rejects_js(t,
-              TypeError, navigator.share({unused: 'unexpected field'}));
-        }, 'share with a dictionary containing only surplus fields');
+      promise_test(async t => {
+        await test_driver.bless("web share", () => {
+          return promise_rejects_js(
+            t,
+            TypeError,
+            navigator.share({ unused: "unexpected field" })
+          );
+        });
+      }, "share with a dictionary containing only surplus fields");
     </script>
   </body>
 </html>
diff --git a/testing/web-platform/tests/web-share/share-url-invalid.https.html b/testing/web-platform/tests/web-share/share-url-invalid.https.html
index ca20cf0c70cc..7c79d9e841e2 100644
--- a/testing/web-platform/tests/web-share/share-url-invalid.https.html
+++ b/testing/web-platform/tests/web-share/share-url-invalid.https.html
@@ -1,20 +1,27 @@
 <!DOCTYPE html>
 <html>
   <head>
-    <meta charset="utf-8">
+    <meta charset="utf-8" />
     <title>WebShare Test: Share with an invalid URL</title>
     <script src="/resources/testharness.js"></script>
     <script src="/resources/testharnessreport.js"></script>
+    <script src="/resources/testdriver-vendor.js"></script>
+    <script src="/resources/testdriver.js"></script>
   </head>
   <body>
     <script>
-        promise_test(t => {
-          // URL is invalid in that the URL Parser returns failure (port is too
-          // large).
-          const url = 'http://example.com:65536';
-          return promise_rejects_js(
-              t, TypeError, navigator.share({url}));
-        }, 'share with an invalid URL');
+      promise_test(async t => {
+        // URL is invalid in that the URL Parser returns failure (port is too
+        // large).
+        const url = "http://example.com:65536";
+        await test_driver.bless(
+          "web share",
+          () => {
+            return promise_rejects_js(t, TypeError, navigator.share({ url }));
+          },
+          "share with an invalid URL"
+        );
+      });
     </script>
   </body>
 </html>