ASSERT under WebAutomationSession::setProcessPool() when running W3C …

…test suite a second time

https://bugs.webkit.org/show_bug.cgi?id=182991
<rdar://problem/37620578>

Reviewed by Timothy Hatcher.

Sometimes when running more than one session end-to-end with the same browser instance,
UIProcess would crash under addMessageReceiver because another WebAutomationSession was still
registered. This is hard to reproduce, but upon code inspection, the receiver management code
is somewhat problematic because it only runs when the WebAutomationSession destructor runs.
In some cases the client could retain two sessions and cause the first one to never remove itself
as the message receiver.

Instead of unregistering the session as a message receiver underneath the session's destructor,
do this whenever a new session supplants an old session since there is only one active session at a time.

* UIProcess/Automation/WebAutomationSession.cpp:
(WebKit::WebAutomationSession::~WebAutomationSession):
* UIProcess/WebProcessPool.cpp:
(WebKit::WebProcessPool::setAutomationSession):


Canonical link: https://commits.webkit.org/198736@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@228854 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebKit/ChangeLog

@@ -1,3 +1,26 @@
+2018-02-20  Brian Burg  <bburg@apple.com>
+
+        ASSERT under WebAutomationSession::setProcessPool() when running W3C test suite a second time
+        https://bugs.webkit.org/show_bug.cgi?id=182991
+        <rdar://problem/37620578>
+
+        Reviewed by Timothy Hatcher.
+
+        Sometimes when running more than one session end-to-end with the same browser instance,
+        UIProcess would crash under addMessageReceiver because another WebAutomationSession was still
+        registered. This is hard to reproduce, but upon code inspection, the receiver management code
+        is somewhat problematic because it only runs when the WebAutomationSession destructor runs.
+        In some cases the client could retain two sessions and cause the first one to never remove itself
+        as the message receiver.
+
+        Instead of unregistering the session as a message receiver underneath the session's destructor,
+        do this whenever a new session supplants an old session since there is only one active session at a time.
+
+        * UIProcess/Automation/WebAutomationSession.cpp:
+        (WebKit::WebAutomationSession::~WebAutomationSession):
+        * UIProcess/WebProcessPool.cpp:
+        (WebKit::WebProcessPool::setAutomationSession):
+
 2018-02-20  Tim Horton  <timothy_horton@apple.com>
 
         Introduce HAVE(IOSURFACE_ACCELERATOR)

Source/WebKit/UIProcess/Automation/WebAutomationSession.cpp

@@ -71,9 +71,7 @@ WebAutomationSession::WebAutomationSession()
 WebAutomationSession::~WebAutomationSession()
 {
     ASSERT(!m_client);
-
-    if (m_processPool)
-        m_processPool->removeMessageReceiver(Messages::WebAutomationSession::messageReceiverName());
+    ASSERT(!m_processPool);
 }
 
 void WebAutomationSession::setClient(std::unique_ptr<API::AutomationSessionClient>&& client)

Source/WebKit/UIProcess/WebProcessPool.cpp

@@ -1502,6 +1502,9 @@ void WebProcessPool::updateAutomationCapabilities() const
 
 void WebProcessPool::setAutomationSession(RefPtr<WebAutomationSession>&& automationSession)
 {
+    if (m_automationSession)
+        m_automationSession->setProcessPool(nullptr);
+
     m_automationSession = WTFMove(automationSession);
 
 #if ENABLE(REMOTE_INSPECTOR)