From af45b352d7c29c42035196bb2d7c5c76a2f303da Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tor=20Arne=20Vestb=C3=B8?=
 <tor.arne.vestbo@theqtcompany.com>
Date: Mon, 11 Jan 2016 19:25:05 +0100
Subject: [PATCH] Fix reentrancy regression in QShortcutMap after c7e5e1d9e

When closing a popup dialog using a shortcut, when the popup
was originally opened using a shortcut, the closing-shortcut
would interfere with the state of the first shortcut, and we
ended up sending a key event for the original shortcut.

Task-number: QTBUG-50360
Change-Id: I62e5ddb9ca43b28519ede629775bc0d7598dccc4
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>
---
 src/gui/kernel/qshortcutmap.cpp               |  8 +++++--
 .../kernel/qshortcut/tst_qshortcut.cpp        | 23 +++++++++++++++++--
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/src/gui/kernel/qshortcutmap.cpp b/src/gui/kernel/qshortcutmap.cpp
index 9c8218b7b5..3941f7233f 100644
--- a/src/gui/kernel/qshortcutmap.cpp
+++ b/src/gui/kernel/qshortcutmap.cpp
@@ -336,12 +336,16 @@ bool QShortcutMap::tryShortcut(QKeyEvent *e)
         // For a partial match we don't know yet if we will handle the shortcut
         // but we need to say we did, so that we get the follow-up key-presses.
         return true;
-    case QKeySequence::ExactMatch:
+    case QKeySequence::ExactMatch: {
+        // Save number of identical matches before dispatching
+        // to keep QShortcutMap and tryShortcut reentrant.
+        const int identicalMatches = d->identicals.count();
         resetState();
         dispatchEvent(e);
         // If there are no identicals we've only found disabled shortcuts, and
         // shouldn't say that we handled the event.
-        return d->identicals.count() > 0;
+        return identicalMatches > 0;
+    }
     default:
         Q_UNREACHABLE();
     }
diff --git a/tests/auto/widgets/kernel/qshortcut/tst_qshortcut.cpp b/tests/auto/widgets/kernel/qshortcut/tst_qshortcut.cpp
index f206a5fe9a..15aef8d503 100644
--- a/tests/auto/widgets/kernel/qshortcut/tst_qshortcut.cpp
+++ b/tests/auto/widgets/kernel/qshortcut/tst_qshortcut.cpp
@@ -72,7 +72,8 @@ public:
         TriggerSlot4,
         TriggerSlot5,
         TriggerSlot6,
-        TriggerSlot7
+        TriggerSlot7,
+        SendKeyEvent
     };
 
     enum Result {
@@ -84,6 +85,7 @@ public:
         Slot5Triggered,
         Slot6Triggered,
         Slot7Triggered,
+        SentKeyEvent,
         Ambiguous
     } currentResult;
 
@@ -104,6 +106,7 @@ public slots:
     void ambigSlot7() { currentResult = Ambiguous; ambigResult = Slot7Triggered; }
     void statusMessage( const QString& message ) { sbText = message; }
     void shortcutDestroyed(QObject* obj);
+    void sendKeyEvent() { sendKeyEvents(edit, Qt::CTRL + Qt::Key_B, 0); currentResult = SentKeyEvent; }
 
 public slots:
     void initTestCase();
@@ -981,6 +984,19 @@ void tst_QShortcut::keypressConsumption()
     QVERIFY(edit->toPlainText().endsWith("<Ctrl+I>a"));
 
     clearAllShortcuts();
+    edit->clear();
+    QCOMPARE(edit->toPlainText().size(), 0);
+
+    setupShortcut(edit, "first", SendKeyEvent, "Ctrl+A");
+
+    // Verify reentrancy when a non-shortcut is triggered as part
+    // of shortcut processing.
+    currentResult = NoResult;
+    ambigResult = NoResult;
+    sendKeyEvents(edit, Qt::CTRL + Qt::Key_A, 0);
+    QCOMPARE(currentResult, SentKeyEvent);
+    QCOMPARE(ambigResult, NoResult);
+    QCOMPARE(edit->toPlainText(), QString(QString("<Ctrl+B>")));
 }
 
 // ------------------------------------------------------------------
@@ -1182,9 +1198,12 @@ QShortcut *tst_QShortcut::setupShortcut(QWidget *parent, const char *name, int t
         normal = SLOT(slotTrig7());
         ambig  = SLOT(ambigSlot7());
         break;
+    case SendKeyEvent:
+        normal = SLOT(sendKeyEvent());
     }
     connect(cut, SIGNAL(activated()), this, normal);
-    connect(cut, SIGNAL(activatedAmbiguously()), this, ambig);
+    if (ambig)
+        connect(cut, SIGNAL(activatedAmbiguously()), this, ambig);
     connect(cut, SIGNAL(destroyed(QObject*)), this, SLOT(shortcutDestroyed(QObject*)));
     shortcuts.append(cut);
     return cut;