Add support for C++ functions attributes in moc

Done-with: Ryan Chu <ryan.chu@qt.io>
Change-Id: Id7f2ba35ccea79e0a0c316ca2736101b8cd57f97
Fixes: QTBUG-58628
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>

src/tools/moc/moc.cpp

@@ -159,6 +159,7 @@ Type Moc::parseType()
     bool isVoid = false;
     type.firstToken = lookup();
     for (;;) {
+        skipCxxAttributes();
         switch (next()) {
             case SIGNED:
             case UNSIGNED:
@@ -188,8 +189,11 @@ Type Moc::parseType()
         }
         break;
     }
+
+    skipCxxAttributes();
     test(ENUM) || test(CLASS) || test(STRUCT);
     for(;;) {
+        skipCxxAttributes();
         switch (next()) {
         case IDENTIFIER:
             // void mySlot(unsigned myArg)
@@ -356,6 +360,15 @@ bool Moc::testFunctionAttribute(Token tok, FunctionDef *def)
     return false;
 }
 
+bool Moc::skipCxxAttributes()
+{
+    auto rewind = index;
+    if (test(LBRACK) && test(LBRACK) && until(RBRACK) && test(RBRACK))
+        return true;
+    index = rewind;
+    return false;
+}
+
 bool Moc::testFunctionRevision(FunctionDef *def)
 {
     if (test(Q_REVISION_TOKEN)) {
@@ -381,7 +394,7 @@ bool Moc::parseFunction(FunctionDef *def, bool inMacro)
     //skip modifiers and attributes
     while (test(INLINE) || (test(STATIC) && (def->isStatic = true) == true) ||
         (test(VIRTUAL) && (def->isVirtual = true) == true) //mark as virtual
-        || testFunctionAttribute(def) || testFunctionRevision(def)) {}
+        || skipCxxAttributes() || testFunctionAttribute(def) || testFunctionRevision(def)) {}
     bool templateFunction = (lookup() == TEMPLATE);
     def->type = parseType();
     if (def->type.name.isEmpty()) {
@@ -454,10 +467,11 @@ bool Moc::parseFunction(FunctionDef *def, bool inMacro)
             until(RBRACE);
         else if ((def->isAbstract = test(EQ)))
             until(SEMIC);
+        else if (skipCxxAttributes())
+            until(SEMIC);
         else
             error();
     }
-
     if (scopedFunctionName) {
         const QByteArray msg = "Function declaration " + def->name
                 + " contains extra qualification. Ignoring as signal or slot.";
@@ -475,7 +489,7 @@ bool Moc::parseMaybeFunction(const ClassDef *cdef, FunctionDef *def)
     //skip modifiers and attributes
     while (test(EXPLICIT) || test(INLINE) || (test(STATIC) && (def->isStatic = true) == true) ||
         (test(VIRTUAL) && (def->isVirtual = true) == true) //mark as virtual
-        || testFunctionAttribute(def) || testFunctionRevision(def)) {}
+        || skipCxxAttributes() || testFunctionAttribute(def) || testFunctionRevision(def)) {}
     bool tilde = test(TILDE);
     def->type = parseType();
     if (def->type.name.isEmpty())

src/tools/moc/moc.h

@@ -257,6 +257,8 @@ public:
     bool testFunctionAttribute(Token tok, FunctionDef *def);
     bool testFunctionRevision(FunctionDef *def);
 
+    bool skipCxxAttributes();
+
     void checkSuperClasses(ClassDef *def);
     void checkProperties(ClassDef* cdef);
 };

tests/auto/tools/moc/cxx-attributes.h

@@ -0,0 +1,60 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef CXXATTRIBUTE_H
+#define CXXATTRIBUTE_H
+
+#include <QtCore/QObject>
+
+class CppAttribute : public QObject
+{
+    Q_OBJECT
+signals:
+    [[deprecated]] void deprecatedSignal();
+
+public slots:
+    [[deprecated]] void deprecatedSlot() {}
+    [[deprecated]] [[tst_moc::maybe_unused]] int deprecatedSlot2() { return 42; }
+    [[deprecated("reason")]] void deprecatedReason() {}
+    [[deprecated("reason[")]] void deprecatedReasonWithLBRACK() {}
+    [[deprecated("reason[[")]] void deprecatedReasonWith2LBRACK() {}
+    [[deprecated("reason]")]] void deprecatedReasonWithRBRACK() {}
+    [[deprecated("reason]]")]] void deprecatedReasonWith2RBRACK() {}
+    void slotWithArguments([[tst_moc::maybe_unused]] int) {}
+#if !defined(_MSC_VER) || _MSC_VER >= 1912
+    // On MSVC it causes:
+    // moc_cxx-attributes.cpp(133): fatal error C1001: An internal error has occurred in the compiler.
+    Q_INVOKABLE [[tst_moc::noreturn]] void noreturnSlot() { throw "unused"; }
+    [[tst_moc::noreturn]] Q_SCRIPTABLE void noreturnSlot2() { throw "unused"; }
+    [[deprecated]] int returnInt() { return 0; }
+    Q_SLOT [[tst_moc::noreturn]] [[deprecated]] void noreturnDeprecatedSlot() { throw "unused"; }
+    Q_INVOKABLE void noreturnSlot3() [[tst_moc::noreturn]] { throw "unused"; }
+#endif
+};
+
+#endif // CXXATTRIBUTE_H

tests/auto/tools/moc/moc.pro

@@ -29,7 +29,8 @@ HEADERS += using-namespaces.h no-keywords.h task87883.h c-comments.h backslash-n
            non-gadget-parent-class.h grand-parent-gadget-class.h \
            related-metaobjects-in-gadget.h \
            related-metaobjects-name-conflict.h \
-           namespace.h cxx17-namespaces.h
+           namespace.h cxx17-namespaces.h \
+           cxx-attributes.h
 
 
 if(*-g++*|*-icc*|*-clang*|*-llvm):!win32-*: HEADERS += os9-newlines.h win-newlines.h

tests/auto/tools/moc/tst_moc.cpp

@@ -71,6 +71,7 @@
 #include "grand-parent-gadget-class.h"
 #include "namespace.h"
 #include "cxx17-namespaces.h"
+#include "cxx-attributes.h"
 
 #ifdef Q_MOC_RUN
 // check that moc can parse these constructs, they are being used in Windows winsock2.h header
@@ -703,6 +704,7 @@ private slots:
     void optionsFileError();
     void testQNamespace();
     void cxx17Namespaces();
+    void cxxAttributes();
 
 signals:
     void sigWithUnsignedArg(unsigned foo);
@@ -3908,6 +3910,24 @@ void tst_Moc::cxx17Namespaces()
     QCOMPARE(QMetaEnum::fromType<CXX17Namespace::A::B::C::D::ClassInNamespace::GadEn>().value(0), 3);
 }
 
+void tst_Moc::cxxAttributes()
+{
+    auto so = CppAttribute::staticMetaObject;
+    QCOMPARE(so.className(), "CppAttribute");
+    QCOMPARE(so.enumeratorCount(), 0);
+    QVERIFY(so.indexOfSignal("deprecatedSignal") != 1);
+    for (auto a: {"deprecatedSlot", "deprecatedSlot2", "deprecatedReason", "deprecatedReasonWithLBRACK",
+                  "deprecatedReasonWith2LBRACK", "deprecatedReasonWithRBRACK", "deprecatedReasonWith2RBRACK",
+                  "slotWithArguments"
+#if !defined(_MSC_VER) || _MSC_VER >= 1912
+                  , "noreturnSlot", "noreturnSlot2", "returnInt", "noreturnDeprecatedSlot",
+                  "noreturnSlot3"
+#endif
+                  }) {
+        QVERIFY(so.indexOfSlot(a) != 1);
+    }
+}
+
 QTEST_MAIN(tst_Moc)
 
 // the generated code must compile with QT_NO_KEYWORDS