1 files changed, 425 insertions, 0 deletions
diff --git a/tests/auto/wasm/qwasmkeytranslator/tst_qwasmkeytranslator.cpp b/tests/auto/wasm/qwasmkeytranslator/tst_qwasmkeytranslator.cpp
new file mode 100644
index 0000000000..de06c298df
--- /dev/null
+++ b/tests/auto/wasm/qwasmkeytranslator/tst_qwasmkeytranslator.cpp
@@ -0,0 +1,425 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+
+#include "../../../../src/plugins/platforms/wasm/qwasmkeytranslator.h"
+
+#include "../../../../src/plugins/platforms/wasm/qwasmevent.h"
+
+#include <QTest>
+
+#include <emscripten/val.h>
+
+namespace {
+emscripten::val makeDeadKeyJsEvent(QString code, Qt::KeyboardModifiers modifiers)
+{
+    auto jsEvent = emscripten::val::object();
+    jsEvent.set("code", emscripten::val(code.toStdString()));
+    jsEvent.set("key", emscripten::val("Dead"));
+    jsEvent.set("shiftKey", emscripten::val(modifiers.testFlag(Qt::ShiftModifier)));
+    jsEvent.set("ctrlKey", emscripten::val(false));
+    jsEvent.set("altKey", emscripten::val(false));
+    jsEvent.set("metaKey", emscripten::val(false));
+
+    return jsEvent;
+}
+
+emscripten::val makeKeyJsEvent(QString code, QString key, Qt::KeyboardModifiers modifiers)
+{
+    auto jsEvent = emscripten::val::object();
+    jsEvent.set("code", emscripten::val(code.toStdString()));
+    jsEvent.set("key", emscripten::val(key.toStdString()));
+    jsEvent.set("shiftKey", emscripten::val(modifiers.testFlag(Qt::ShiftModifier)));
+    jsEvent.set("ctrlKey", emscripten::val(modifiers.testFlag(Qt::ControlModifier)));
+    jsEvent.set("altKey", emscripten::val(modifiers.testFlag(Qt::AltModifier)));
+    jsEvent.set("metaKey", emscripten::val(modifiers.testFlag(Qt::MetaModifier)));
+
+    return jsEvent;
+}
+} // unnamed namespace
+
+class tst_QWasmKeyTranslator : public QObject
+{
+    Q_OBJECT
+
+public:
+    tst_QWasmKeyTranslator() = default;
+
+private slots:
+    void init();
+
+    void modifyByDeadKey_data();
+    void modifyByDeadKey();
+    void deadKeyModifiesOnlyOneKeyPressAndUp();
+    void deadKeyIgnoresKeyUpPrecedingKeyDown();
+    void onlyKeysProducingTextAreModifiedByDeadKeys();
+};
+
+void tst_QWasmKeyTranslator::init() { }
+
+void tst_QWasmKeyTranslator::modifyByDeadKey_data()
+{
+    QTest::addColumn<QString>("deadKeyCode");
+    QTest::addColumn<Qt::KeyboardModifiers>("deadKeyModifiers");
+    QTest::addColumn<QString>("targetKeyCode");
+    QTest::addColumn<QString>("targetKey");
+    QTest::addColumn<Qt::Key>("targetQtKey");
+    QTest::addColumn<Qt::KeyboardModifiers>("modifiers");
+    QTest::addColumn<QString>("expectedModifiedKey");
+
+    QTest::newRow("à (Backquote)") << "Backquote" << Qt::KeyboardModifiers() << "KeyA"
+                                   << "a" << Qt::Key_Agrave << Qt::KeyboardModifiers() << "à";
+    QTest::newRow("À (Backquote)")
+            << "Backquote" << Qt::KeyboardModifiers() << "KeyA"
+            << "A" << Qt::Key_Agrave << Qt::KeyboardModifiers(Qt::ShiftModifier) << "À";
+    QTest::newRow("à (IntlBackslash)") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyA"
+                                       << "a" << Qt::Key_Agrave << Qt::KeyboardModifiers() << "à";
+    QTest::newRow("À (IntlBackslash)")
+            << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyA"
+            << "A" << Qt::Key_Agrave << Qt::KeyboardModifiers(Qt::ShiftModifier) << "À";
+    QTest::newRow("á (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyA"
+                               << "a" << Qt::Key_Aacute << Qt::KeyboardModifiers() << "á";
+    QTest::newRow("Á (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyA"
+                               << "A" << Qt::Key_Aacute << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                               << "Á";
+    QTest::newRow("á") << "KeyE" << Qt::KeyboardModifiers() << "KeyA"
+                       << "a" << Qt::Key_Aacute << Qt::KeyboardModifiers() << "á";
+    QTest::newRow("Á") << "KeyE" << Qt::KeyboardModifiers() << "KeyA"
+                       << "A" << Qt::Key_Aacute << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Á";
+    QTest::newRow("ä (Mac Umlaut)") << "KeyU" << Qt::KeyboardModifiers() << "KeyA"
+                                    << "a" << Qt::Key_Adiaeresis << Qt::KeyboardModifiers() << "ä";
+    QTest::newRow("Ä (Mac Umlaut)")
+            << "KeyU" << Qt::KeyboardModifiers() << "KeyA"
+            << "A" << Qt::Key_Adiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ä";
+    QTest::newRow("ä (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyA"
+            << "a" << Qt::Key_Adiaeresis << Qt::KeyboardModifiers() << "ä";
+    QTest::newRow("Ä (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyA"
+            << "A" << Qt::Key_Adiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ä";
+    QTest::newRow("â") << "KeyI" << Qt::KeyboardModifiers() << "KeyA"
+                       << "a" << Qt::Key_Acircumflex << Qt::KeyboardModifiers() << "â";
+    QTest::newRow("Â") << "KeyI" << Qt::KeyboardModifiers() << "KeyA"
+                       << "A" << Qt::Key_Acircumflex << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                       << "Â";
+    QTest::newRow("â (^ key)") << "Digit6" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyA"
+                               << "a" << Qt::Key_Acircumflex << Qt::KeyboardModifiers() << "â";
+    QTest::newRow("Â (^ key)") << "Digit6" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyA"
+                               << "A" << Qt::Key_Acircumflex
+                               << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Â";
+    QTest::newRow("ã") << "KeyN" << Qt::KeyboardModifiers() << "KeyA"
+                       << "a" << Qt::Key_Atilde << Qt::KeyboardModifiers() << "ã";
+    QTest::newRow("Ã") << "KeyN" << Qt::KeyboardModifiers() << "KeyA"
+                       << "A" << Qt::Key_Atilde << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ã";
+
+    QTest::newRow("è (Backquote)") << "Backquote" << Qt::KeyboardModifiers() << "KeyE"
+                                   << "e" << Qt::Key_Egrave << Qt::KeyboardModifiers() << "è";
+    QTest::newRow("È (Backquote)")
+            << "Backquote" << Qt::KeyboardModifiers() << "KeyE"
+            << "E" << Qt::Key_Egrave << Qt::KeyboardModifiers(Qt::ShiftModifier) << "È";
+    QTest::newRow("è") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyE"
+                       << "e" << Qt::Key_Egrave << Qt::KeyboardModifiers() << "è";
+    QTest::newRow("È") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyE"
+                       << "E" << Qt::Key_Egrave << Qt::KeyboardModifiers(Qt::ShiftModifier) << "È";
+    QTest::newRow("é") << "KeyE" << Qt::KeyboardModifiers() << "KeyE"
+                       << "e" << Qt::Key_Eacute << Qt::KeyboardModifiers() << "é";
+    QTest::newRow("É") << "KeyE" << Qt::KeyboardModifiers() << "KeyE"
+                       << "E" << Qt::Key_Eacute << Qt::KeyboardModifiers(Qt::ShiftModifier) << "É";
+    QTest::newRow("é (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyE"
+                               << "e" << Qt::Key_Eacute << Qt::KeyboardModifiers() << "é";
+    QTest::newRow("É (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyE"
+                               << "E" << Qt::Key_Eacute << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                               << "É";
+    QTest::newRow("ë (Mac Umlaut)") << "KeyU" << Qt::KeyboardModifiers() << "KeyE"
+                                    << "e" << Qt::Key_Ediaeresis << Qt::KeyboardModifiers() << "ë";
+    QTest::newRow("Ë (Mac Umlaut)")
+            << "KeyU" << Qt::KeyboardModifiers() << "KeyE"
+            << "E" << Qt::Key_Ediaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ë";
+    QTest::newRow("ë (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyE"
+            << "e" << Qt::Key_Ediaeresis << Qt::KeyboardModifiers() << "ë";
+    QTest::newRow("Ë (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyE"
+            << "E" << Qt::Key_Ediaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ë";
+    QTest::newRow("ê") << "KeyI" << Qt::KeyboardModifiers() << "KeyE"
+                       << "e" << Qt::Key_Ecircumflex << Qt::KeyboardModifiers() << "ê";
+    QTest::newRow("Ê") << "KeyI" << Qt::KeyboardModifiers() << "KeyE"
+                       << "E" << Qt::Key_Ecircumflex << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                       << "Ê";
+    QTest::newRow("ê (^ key)") << "Digit6" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyE"
+                               << "e" << Qt::Key_Ecircumflex << Qt::KeyboardModifiers() << "ê";
+    QTest::newRow("Ê (^ key)") << "Digit6" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyE"
+                               << "E" << Qt::Key_Ecircumflex
+                               << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ê";
+
+    QTest::newRow("ì (Backquote)") << "Backquote" << Qt::KeyboardModifiers() << "KeyI"
+                                   << "i" << Qt::Key_Igrave << Qt::KeyboardModifiers() << "ì";
+    QTest::newRow("Ì (Backquote)")
+            << "Backquote" << Qt::KeyboardModifiers() << "KeyI"
+            << "I" << Qt::Key_Igrave << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ì";
+    QTest::newRow("ì") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyI"
+                       << "i" << Qt::Key_Igrave << Qt::KeyboardModifiers() << "ì";
+    QTest::newRow("Ì") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyI"
+                       << "I" << Qt::Key_Igrave << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ì";
+    QTest::newRow("í") << "KeyE" << Qt::KeyboardModifiers() << "KeyI"
+                       << "i" << Qt::Key_Iacute << Qt::KeyboardModifiers() << "í";
+    QTest::newRow("Í") << "KeyE" << Qt::KeyboardModifiers() << "KeyI"
+                       << "I" << Qt::Key_Iacute << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Í";
+    QTest::newRow("í (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyI"
+                               << "i" << Qt::Key_Iacute << Qt::KeyboardModifiers() << "í";
+    QTest::newRow("Í (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyI"
+                               << "I" << Qt::Key_Iacute << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                               << "Í";
+    QTest::newRow("ï (Mac Umlaut)") << "KeyU" << Qt::KeyboardModifiers() << "KeyI"
+                                    << "i" << Qt::Key_Idiaeresis << Qt::KeyboardModifiers() << "ï";
+    QTest::newRow("Ï (Mac Umlaut)")
+            << "KeyU" << Qt::KeyboardModifiers() << "KeyI"
+            << "I" << Qt::Key_Idiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ï";
+    QTest::newRow("ï (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyI"
+            << "i" << Qt::Key_Idiaeresis << Qt::KeyboardModifiers() << "ï";
+    QTest::newRow("Ï (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyI"
+            << "I" << Qt::Key_Idiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ï";
+    QTest::newRow("î") << "KeyI" << Qt::KeyboardModifiers() << "KeyI"
+                       << "i" << Qt::Key_Icircumflex << Qt::KeyboardModifiers() << "î";
+    QTest::newRow("Î") << "KeyI" << Qt::KeyboardModifiers() << "KeyI"
+                       << "I" << Qt::Key_Icircumflex << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                       << "Î";
+    QTest::newRow("î (^ key)") << "Digit6" << Qt::KeyboardModifiers() << "KeyI"
+                               << "i" << Qt::Key_Icircumflex << Qt::KeyboardModifiers() << "î";
+    QTest::newRow("Î (^ key)") << "Digit6" << Qt::KeyboardModifiers() << "KeyI"
+                               << "I" << Qt::Key_Icircumflex
+                               << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Î";
+
+    QTest::newRow("ñ") << "KeyN" << Qt::KeyboardModifiers() << "KeyN"
+                       << "n" << Qt::Key_Ntilde << Qt::KeyboardModifiers() << "ñ";
+    QTest::newRow("Ñ") << "KeyN" << Qt::KeyboardModifiers() << "KeyN"
+                       << "N" << Qt::Key_Ntilde << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ñ";
+
+    QTest::newRow("ò (Backquote)") << "Backquote" << Qt::KeyboardModifiers() << "KeyO"
+                                   << "o" << Qt::Key_Ograve << Qt::KeyboardModifiers() << "ò";
+    QTest::newRow("Ò (Backquote)")
+            << "Backquote" << Qt::KeyboardModifiers() << "KeyO"
+            << "O" << Qt::Key_Ograve << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ò";
+    QTest::newRow("ò") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyO"
+                       << "o" << Qt::Key_Ograve << Qt::KeyboardModifiers() << "ò";
+    QTest::newRow("Ò") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyO"
+                       << "O" << Qt::Key_Ograve << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ò";
+    QTest::newRow("ó") << "KeyE" << Qt::KeyboardModifiers() << "KeyO"
+                       << "o" << Qt::Key_Oacute << Qt::KeyboardModifiers() << "ó";
+    QTest::newRow("Ó") << "KeyE" << Qt::KeyboardModifiers() << "KeyO"
+                       << "O" << Qt::Key_Oacute << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ó";
+    QTest::newRow("ó (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyO"
+                               << "o" << Qt::Key_Oacute << Qt::KeyboardModifiers() << "ó";
+    QTest::newRow("Ó  (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyO"
+                                << "O" << Qt::Key_Oacute << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                                << "Ó";
+    QTest::newRow("ö (Mac Umlaut)") << "KeyU" << Qt::KeyboardModifiers() << "KeyO"
+                                    << "o" << Qt::Key_Odiaeresis << Qt::KeyboardModifiers() << "ö";
+    QTest::newRow("Ö (Mac Umlaut)")
+            << "KeyU" << Qt::KeyboardModifiers() << "KeyO"
+            << "O" << Qt::Key_Odiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ö";
+    QTest::newRow("ö (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyO"
+            << "o" << Qt::Key_Odiaeresis << Qt::KeyboardModifiers() << "ö";
+    QTest::newRow("Ö (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyO"
+            << "O" << Qt::Key_Odiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ö";
+    QTest::newRow("ô") << "KeyI" << Qt::KeyboardModifiers() << "KeyO"
+                       << "o" << Qt::Key_Ocircumflex << Qt::KeyboardModifiers() << "ô";
+    QTest::newRow("Ô") << "KeyI" << Qt::KeyboardModifiers() << "KeyO"
+                       << "O" << Qt::Key_Ocircumflex << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                       << "Ô";
+    QTest::newRow("ô (^ key)") << "Digit6" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyO"
+                               << "o" << Qt::Key_Ocircumflex << Qt::KeyboardModifiers() << "ô";
+    QTest::newRow("Ô (^ key)") << "Digit6" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyO"
+                               << "O" << Qt::Key_Ocircumflex
+                               << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ô";
+    QTest::newRow("õ") << "KeyN" << Qt::KeyboardModifiers() << "KeyO"
+                       << "o" << Qt::Key_Otilde << Qt::KeyboardModifiers() << "õ";
+    QTest::newRow("Õ") << "KeyN" << Qt::KeyboardModifiers() << "KeyO"
+                       << "O" << Qt::Key_Otilde << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Õ";
+
+    QTest::newRow("ù (Backquote)") << "Backquote" << Qt::KeyboardModifiers() << "KeyU"
+                                   << "u" << Qt::Key_Ugrave << Qt::KeyboardModifiers() << "ù";
+    QTest::newRow("Ù (Backquote)")
+            << "Backquote" << Qt::KeyboardModifiers() << "KeyU"
+            << "U" << Qt::Key_Ugrave << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ù";
+    QTest::newRow("ù") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyU"
+                       << "u" << Qt::Key_Ugrave << Qt::KeyboardModifiers() << "ù";
+    QTest::newRow("Ù") << "IntlBackslash" << Qt::KeyboardModifiers() << "KeyU"
+                       << "U" << Qt::Key_Ugrave << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ù";
+    QTest::newRow("ú") << "KeyE" << Qt::KeyboardModifiers() << "KeyU"
+                       << "u" << Qt::Key_Uacute << Qt::KeyboardModifiers() << "ú";
+    QTest::newRow("Ú") << "KeyE" << Qt::KeyboardModifiers() << "KeyU"
+                       << "U" << Qt::Key_Uacute << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ú";
+    QTest::newRow("ú (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyU"
+                               << "u" << Qt::Key_Uacute << Qt::KeyboardModifiers() << "ú";
+    QTest::newRow("Ú (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyU"
+                               << "U" << Qt::Key_Uacute << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                               << "Ú";
+    QTest::newRow("ü (Mac Umlaut)") << "KeyU" << Qt::KeyboardModifiers() << "KeyU"
+                                    << "u" << Qt::Key_Udiaeresis << Qt::KeyboardModifiers() << "ü";
+    QTest::newRow("Ü (Mac Umlaut)")
+            << "KeyU" << Qt::KeyboardModifiers() << "KeyU"
+            << "U" << Qt::Key_Udiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ü";
+    QTest::newRow("ü (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyU"
+            << "u" << Qt::Key_Udiaeresis << Qt::KeyboardModifiers() << "ü";
+    QTest::newRow("Ü (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyU"
+            << "U" << Qt::Key_Udiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ü";
+    QTest::newRow("û") << "KeyI" << Qt::KeyboardModifiers() << "KeyU"
+                       << "û" << Qt::Key_Ucircumflex << Qt::KeyboardModifiers() << "û";
+    QTest::newRow("Û") << "KeyI" << Qt::KeyboardModifiers() << "KeyU"
+                       << "U" << Qt::Key_Ucircumflex << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                       << "Û";
+    QTest::newRow("û (^ key)") << "Digit6" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyU"
+                               << "û" << Qt::Key_Ucircumflex << Qt::KeyboardModifiers() << "û";
+    QTest::newRow("Û (^ key)") << "Digit6" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyU"
+                               << "U" << Qt::Key_Ucircumflex
+                               << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Û";
+
+    QTest::newRow("ý") << "KeyE" << Qt::KeyboardModifiers() << "KeyY"
+                       << "y" << Qt::Key_Yacute << Qt::KeyboardModifiers() << "ý";
+    QTest::newRow("Ý") << "KeyE" << Qt::KeyboardModifiers() << "KeyY"
+                       << "Y" << Qt::Key_Yacute << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ý";
+    QTest::newRow("ý (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyY"
+                               << "y" << Qt::Key_Yacute << Qt::KeyboardModifiers() << "ý";
+    QTest::newRow("Ý (Quote)") << "Quote" << Qt::KeyboardModifiers() << "KeyY"
+                               << "Y" << Qt::Key_Yacute << Qt::KeyboardModifiers(Qt::ShiftModifier)
+                               << "Ý";
+    QTest::newRow("ÿ (Mac Umlaut)") << "KeyU" << Qt::KeyboardModifiers() << "KeyY"
+                                    << "y" << Qt::Key_ydiaeresis << Qt::KeyboardModifiers() << "ÿ";
+    QTest::newRow("Ÿ (Mac Umlaut)")
+            << "KeyU" << Qt::KeyboardModifiers() << "KeyY"
+            << "Y" << Qt::Key_ydiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ÿ";
+    QTest::newRow("ÿ (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyY"
+            << "y" << Qt::Key_ydiaeresis << Qt::KeyboardModifiers() << "ÿ";
+    QTest::newRow("Ÿ (Shift+Quote)")
+            << "Quote" << Qt::KeyboardModifiers(Qt::ShiftModifier) << "KeyY"
+            << "Y" << Qt::Key_ydiaeresis << Qt::KeyboardModifiers(Qt::ShiftModifier) << "Ÿ";
+}
+
+void tst_QWasmKeyTranslator::modifyByDeadKey()
+{
+    QFETCH(QString, deadKeyCode);
+    QFETCH(Qt::KeyboardModifiers, deadKeyModifiers);
+    QFETCH(QString, targetKeyCode);
+    QFETCH(QString, targetKey);
+    QFETCH(Qt::Key, targetQtKey);
+    QFETCH(Qt::KeyboardModifiers, modifiers);
+    QFETCH(QString, expectedModifiedKey);
+
+    QWasmDeadKeySupport deadKeySupport;
+
+    KeyEvent event(EventType::KeyDown, makeDeadKeyJsEvent(deadKeyCode, deadKeyModifiers));
+    QCOMPARE(event.deadKey, true);
+
+    deadKeySupport.applyDeadKeyTranslations(&event);
+
+    KeyEvent eDown(EventType::KeyDown, makeKeyJsEvent(targetKeyCode, targetKey, modifiers));
+    QCOMPARE(eDown.deadKey, false);
+    deadKeySupport.applyDeadKeyTranslations(&eDown);
+    QCOMPARE(eDown.deadKey, false);
+    QCOMPARE(eDown.text, expectedModifiedKey);
+    QCOMPARE(eDown.key, targetQtKey);
+
+    KeyEvent eUp(EventType::KeyUp, makeKeyJsEvent(targetKeyCode, targetKey, modifiers));
+    QCOMPARE(eUp.deadKey, false);
+    deadKeySupport.applyDeadKeyTranslations(&eUp);
+    QCOMPARE(eUp.text, expectedModifiedKey);
+    QCOMPARE(eUp.key, targetQtKey);
+}
+
+void tst_QWasmKeyTranslator::deadKeyModifiesOnlyOneKeyPressAndUp()
+{
+    QWasmDeadKeySupport deadKeySupport;
+    KeyEvent event(EventType::KeyDown, makeDeadKeyJsEvent("KeyU", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&event);
+
+    KeyEvent eDown(EventType::KeyDown, makeKeyJsEvent("KeyU", "u", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&eDown);
+    QCOMPARE(eDown.text, "ü");
+    QCOMPARE(eDown.key, Qt::Key_Udiaeresis);
+
+    KeyEvent eUp(EventType::KeyUp, makeKeyJsEvent("KeyU", "u", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&eUp);
+    QCOMPARE(eUp.text, "ü");
+    QCOMPARE(eUp.key, Qt::Key_Udiaeresis);
+
+    KeyEvent eDown2(EventType::KeyDown, makeKeyJsEvent("KeyU", "u", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&eDown2);
+    QCOMPARE(eDown2.text, "u");
+    QCOMPARE(eDown2.key, Qt::Key_U);
+
+    KeyEvent eUp2(EventType::KeyUp, makeKeyJsEvent("KeyU", "u", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&eUp2);
+    QCOMPARE(eUp2.text, "u");
+    QCOMPARE(eUp2.key, Qt::Key_U);
+}
+
+void tst_QWasmKeyTranslator::deadKeyIgnoresKeyUpPrecedingKeyDown()
+{
+    QWasmDeadKeySupport deadKeySupport;
+
+    KeyEvent deadKeyDownEvent(EventType::KeyDown,
+                              makeDeadKeyJsEvent("KeyU", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&deadKeyDownEvent);
+
+    KeyEvent deadKeyUpEvent(EventType::KeyUp, makeDeadKeyJsEvent("KeyU", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&deadKeyUpEvent);
+
+    KeyEvent otherKeyUpEvent(EventType::KeyUp,
+                             makeKeyJsEvent("AltLeft", "Alt", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&otherKeyUpEvent);
+
+    KeyEvent eDown(EventType::KeyDown, makeKeyJsEvent("KeyU", "u", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&eDown);
+    QCOMPARE(eDown.text, "ü");
+    QCOMPARE(eDown.key, Qt::Key_Udiaeresis);
+
+    KeyEvent yetAnotherKeyUpEvent(
+            EventType::KeyUp, makeKeyJsEvent("ControlLeft", "Control", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&yetAnotherKeyUpEvent);
+
+    KeyEvent eUp(EventType::KeyUp, makeKeyJsEvent("KeyU", "u", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&eUp);
+    QCOMPARE(eUp.text, "ü");
+    QCOMPARE(eUp.key, Qt::Key_Udiaeresis);
+}
+
+void tst_QWasmKeyTranslator::onlyKeysProducingTextAreModifiedByDeadKeys()
+{
+    QWasmDeadKeySupport deadKeySupport;
+
+    KeyEvent deadKeyDownEvent(EventType::KeyDown,
+                              makeDeadKeyJsEvent("KeyU", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&deadKeyDownEvent);
+
+    KeyEvent noTextKeyDown(EventType::KeyDown,
+                           makeKeyJsEvent("AltLeft", "Alt", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&noTextKeyDown);
+    QCOMPARE(noTextKeyDown.text, "");
+    QCOMPARE(noTextKeyDown.key, Qt::Key_Alt);
+
+    KeyEvent noTextKeyUp(EventType::KeyUp,
+                         makeKeyJsEvent("AltLeft", "Alt", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&noTextKeyUp);
+    QCOMPARE(noTextKeyDown.text, "");
+    QCOMPARE(noTextKeyDown.key, Qt::Key_Alt);
+
+    KeyEvent eDown(EventType::KeyDown, makeKeyJsEvent("KeyU", "u", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&eDown);
+    QCOMPARE(eDown.text, "ü");
+    QCOMPARE(eDown.key, Qt::Key_Udiaeresis);
+
+    KeyEvent eUp(EventType::KeyUp, makeKeyJsEvent("KeyU", "u", Qt::KeyboardModifiers()));
+    deadKeySupport.applyDeadKeyTranslations(&eUp);
+    QCOMPARE(eUp.text, "ü");
+    QCOMPARE(eUp.key, Qt::Key_Udiaeresis);
+}
+
+QTEST_MAIN(tst_QWasmKeyTranslator)
+#include "tst_qwasmkeytranslator.moc"