Add QT_TR*_N_NOOP() macros

[ChangeLog][QtCore][Global] Added the QT_TR_N_NOOP(),
QT_TRANSLATE_N_NOOP(), and QT_TRANSLATE_N_NOOP3() macros for numeral
dependent delayed translation.

Change-Id: I57c5b1ad4006267f49a57b0cbc40216b8e0399ff
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>
Reviewed-by: Martin Smith <martin.smith@qt.io>

src/corelib/doc/snippets/code/src_corelib_global_qglobal.cpp

@@ -440,6 +440,54 @@ QString global_greeting(int type)
 //! [36]
 
 
+//! [qttrnnoop]
+static const char * const StatusClass::status_strings[] = {
+    QT_TR_N_NOOP("There are %n new message(s)"),
+    QT_TR_N_NOOP("There are %n total message(s)")
+};
+
+QString StatusClass::status(int type, int count)
+{
+    return tr(status_strings[type], nullptr, count);
+}
+//! [qttrnnoop]
+
+//! [qttranslatennoop]
+static const char * const greeting_strings[] = {
+    QT_TRANSLATE_N_NOOP("Welcome Msg", "Hello, you have %n message(s)"),
+    QT_TRANSLATE_N_NOOP("Welcome Msg", "Hi, you have %n message(s)")
+};
+
+QString global_greeting(int type, int msgcnt)
+{
+    return translate("Welcome Msg", greeting_strings[type], nullptr, msgcnt);
+}
+//! [qttranslatennoop]
+
+//! [qttranslatennoop3]
+static { const char * const source; const char * const comment; } status_strings[] = {
+    QT_TRANSLATE_N_NOOP3("Message Status", "Hello, you have %n message(s)",
+                         "A login message status"),
+    QT_TRANSLATE_N_NOOP3("Message status", "You have %n new message(s)",
+                         "A new message query status")
+};
+
+QString FriendlyConversation::greeting(int type, int count)
+{
+    return tr(status_strings[type].source,
+              status_strings[type].comment, count);
+}
+
+QString global_greeting(int type, int count)
+{
+    return qApp->translate("Message Status",
+                           status_strings[type].source,
+                           status_strings[type].comment,
+                           count);
+}
+//! [qttranslatennoop3]
+
+
 //! [qttrid]
     //% "%n fooish bar(s) found.\n"
     //% "Do you want to continue?"

src/corelib/global/qglobal.cpp

@@ -650,7 +650,8 @@ Q_STATIC_ASSERT((std::is_same<qsizetype, qptrdiff>::value));
     The remaining macros are convenience macros for larger operations:
     The QT_TR_NOOP(), QT_TRANSLATE_NOOP(), and QT_TRANSLATE_NOOP3()
     macros provide the possibility of marking strings for delayed
-    translation.
+    translation. QT_TR_N_NOOP(), QT_TRANSLATE_N_NOOP(), and
+    QT_TRANSLATE_N_NOOP3() are numerator dependent variants of these.
     The Q_ASSERT() and Q_ASSERT_X() enables warning messages of various
     level of refinement. The Q_FOREACH() and foreach() macros
     implement Qt's foreach loop.
@@ -3732,6 +3733,71 @@ bool qunsetenv(const char *varName)
     \sa QT_TR_NOOP(), QT_TRANSLATE_NOOP(), {Internationalization with Qt}
 */
 
+/*!
+    \macro QT_TR_N_NOOP(sourceText)
+    \relates <QtGlobal>
+    \since 5.12
+
+    Marks the UTF-8 encoded string literal \a sourceText for numerator
+    dependent delayed translation in the current context (class).
+
+    The macro tells lupdate to collect the string, and expands to
+    \a sourceText itself.
+
+    The macro expands to \a sourceText.
+
+    Example:
+
+    \snippet code/src_corelib_global_qglobal.cpp qttrnnoop
+
+    \sa QT_TR_NOOP, {Internationalization with Qt}
+*/
+
+/*!
+    \macro QT_TRANSLATE_N_NOOP(context, sourceText)
+    \relates <QtGlobal>
+    \since 5.12
+
+    Marks the UTF-8 encoded string literal \a sourceText for numerator
+    dependent delayed translation in the given \a context.
+    The \a context is typically a class name and also needs to be
+    specified as a string literal.
+
+    The macro tells lupdate to collect the string, and expands to
+    \a sourceText itself.
+
+    Example:
+
+    \snippet code/src_corelib_global_qglobal.cpp qttranslatennoop
+
+    \sa QT_TRANSLATE_NOOP(), QT_TRANSLATE_N_NOOP3(),
+    {Internationalization with Qt}
+*/
+
+/*!
+    \macro QT_TRANSLATE_N_NOOP3(context, sourceText, comment)
+    \relates <QtGlobal>
+    \since 5.12
+
+    Marks the UTF-8 encoded string literal \a sourceText for numerator
+    dependent delayed translation in the given \a context with the given
+    \a disambiguation.
+    The \a context is typically a class and also needs to be specified
+    as a string literal. The string literal \a disambiguation should be
+    a short semantic tag to tell apart otherwise identical strings.
+
+    The macro tells lupdate to collect the string, and expands to an
+    anonymous struct of the two string literals passed as \a sourceText
+    and \a disambiguation.
+
+    Example:
+
+    \snippet code/src_corelib_global_qglobal.cpp qttranslatennoop3
+
+    \sa QT_TR_NOOP(), QT_TRANSLATE_NOOP(), QT_TRANSLATE_NOOP3(),
+    {Internationalization with Qt}
+*/
+
 /*!
     \fn QString qtTrId(const char *id, int n = -1)
     \relates <QtGlobal>

src/corelib/global/qglobal.h

@@ -1064,6 +1064,10 @@ template <typename Ptr> inline auto qGetPtrHelper(const Ptr &ptr) -> decltype(pt
 
 #ifndef QT_NO_TRANSLATION // ### Qt6: This should enclose the NOOPs above
 
+#define QT_TR_N_NOOP(x) x
+#define QT_TRANSLATE_N_NOOP(scope, x) x
+#define QT_TRANSLATE_N_NOOP3(scope, x, comment) {x, comment}
+
 // Defined in qcoreapplication.cpp
 // The better name qTrId() is reserved for an upcoming function which would
 // return a much more powerful QStringFormatter instead of a QString.