Introduce Q_MOC_INCLUDE

A new macro that can be added in the header file parsed by moc to tell moc
to include that file in the generated file

Change-Id: I03ad702c3fcd8380371015f226ee4b7456daf132
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/kernel/qobject.cpp

@@ -4542,6 +4542,23 @@ QDebug operator<<(QDebug dbg, const QObject *o)
     \sa Q_NAMESPACE, {Creating Shared Libraries}
 */
 
+/*!
+    \macro Q_MOC_INCLUDE
+    \relates QObject
+    \since 6.0
+
+    The Q_MOC_INCLUDE macro can be used within or outside a class, and tell the
+    \l{moc}{Meta Object Compiler} to add an include.
+
+    \code
+        // Put this in your code and the generated code will include this header.
+        Q_MOC_INCLUDE("myheader.h")
+    \endcode
+
+    This is useful if the types you use as properties or signal/slots arguments
+    are forward declared.
+*/
+
 /*!
     \macro Q_SIGNALS
     \relates QObject

src/corelib/kernel/qtmetamacros.h

@@ -112,6 +112,7 @@ QT_BEGIN_NAMESPACE
 #define Q_INVOKABLE  QT_ANNOTATE_FUNCTION(qt_invokable)
 #define Q_SIGNAL QT_ANNOTATE_FUNCTION(qt_signal)
 #define Q_SLOT QT_ANNOTATE_FUNCTION(qt_slot)
+#define Q_MOC_INCLUDE(...) QT_ANNOTATE_CLASS(qt_moc_include, __VA_ARGS__)
 #endif // QT_NO_META_MACROS
 
 #ifndef QT_NO_TRANSLATION

src/tools/moc/keywords.cpp

@@ -30,12 +30,12 @@
 // DO NOT EDIT.
 
 static const short keyword_trans[][128] = {
-    {0,0,0,0,0,0,0,0,0,568,565,0,0,0,0,0,
+    {0,0,0,0,0,0,0,0,0,579,576,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     568,252,566,569,8,38,239,567,25,26,236,234,30,235,27,237,
+     579,252,577,580,8,38,239,578,25,26,236,234,30,235,27,237,
      22,22,22,22,22,22,22,22,22,22,34,41,23,39,24,43,
      0,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
-     8,21,8,8,8,8,8,8,8,8,8,31,571,32,238,8,
+     8,21,8,8,8,8,8,8,8,8,8,31,582,32,238,8,
      0,1,2,3,4,5,6,7,8,9,8,8,10,11,12,13,
      14,8,15,16,17,18,19,20,8,8,8,36,245,37,248,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -177,7 +177,7 @@ static const short keyword_trans[][128] = {
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,42,0,0,0,28,0,
-     574,574,574,574,574,574,574,574,574,574,0,0,0,0,0,0,
+     585,585,585,585,585,585,585,585,585,585,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -336,7 +336,7 @@ static const short keyword_trans[][128] = {
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,0,0,0,0,0,0,573,0,0,0,0,572,
+     0,0,0,0,0,0,0,0,0,0,584,0,0,0,0,583,
      0,0,0,0,0,0,0,0,0,0,0,0,0,258,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -378,7 +378,7 @@ static const short keyword_trans[][128] = {
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,475,424,408,416,380,0,484,0,0,0,0,364,358,
+     0,0,0,475,424,408,416,380,0,484,0,0,0,565,364,358,
      386,0,557,472,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
@@ -1021,11 +1021,22 @@ static const struct
     {CHARACTER, 0, 79, 563, CHARACTER},
     {CHARACTER, 0, 78, 564, CHARACTER},
     {Q_REVISION_TOKEN, 0, 0, 0, CHARACTER},
+    {CHARACTER, 0, 79, 566, CHARACTER},
+    {CHARACTER, 0, 67, 567, CHARACTER},
+    {CHARACTER, 0, 95, 568, CHARACTER},
+    {CHARACTER, 0, 73, 569, CHARACTER},
+    {CHARACTER, 0, 78, 570, CHARACTER},
+    {CHARACTER, 0, 67, 571, CHARACTER},
+    {CHARACTER, 0, 76, 572, CHARACTER},
+    {CHARACTER, 0, 85, 573, CHARACTER},
+    {CHARACTER, 0, 68, 574, CHARACTER},
+    {CHARACTER, 0, 69, 575, CHARACTER},
+    {Q_MOC_INCLUDE_TOKEN, 0, 0, 0, CHARACTER},
     {NEWLINE, 0, 0, 0, NOTOKEN},
     {QUOTE, 0, 0, 0, NOTOKEN},
     {SINGLEQUOTE, 0, 0, 0, NOTOKEN},
     {WHITESPACE, 0, 0, 0, NOTOKEN},
-    {HASH, 0, 35, 570, HASH},
+    {HASH, 0, 35, 581, HASH},
     {PP_HASHHASH, 0, 0, 0, NOTOKEN},
     {BACKSLASH, 0, 0, 0, NOTOKEN},
     {CPP_COMMENT, 0, 0, 0, NOTOKEN},

src/tools/moc/moc.cpp

@@ -653,6 +653,11 @@ void Moc::parse()
                             case Q_CLASSINFO_TOKEN:
                                 parseClassInfo(&def);
                                 break;
+                            case Q_MOC_INCLUDE_TOKEN:
+                                // skip it, the namespace is parsed twice
+                                next(LPAREN);
+                                lexemUntil(RPAREN);
+                                break;
                             case ENUM: {
                                 EnumDef enumDef;
                                 if (parseEnum(&enumDef))
@@ -696,6 +701,9 @@ void Moc::parse()
             case Q_DECLARE_METATYPE_TOKEN:
                 parseDeclareMetatype();
                 break;
+            case Q_MOC_INCLUDE_TOKEN:
+                parseMocInclude();
+                break;
             case USING:
                 if (test(NAMESPACE)) {
                     while (test(SCOPE) || test(IDENTIFIER))
@@ -828,6 +836,9 @@ void Moc::parse()
                 case Q_CLASSINFO_TOKEN:
                     parseClassInfo(&def);
                     break;
+                case Q_MOC_INCLUDE_TOKEN:
+                    parseMocInclude();
+                    break;
                 case Q_INTERFACES_TOKEN:
                     parseInterfaces(&def);
                     break;
@@ -1562,6 +1573,16 @@ void Moc::parseDeclareMetatype()
     metaTypes.append(typeName);
 }
 
+void Moc::parseMocInclude()
+{
+    next(LPAREN);
+    QByteArray include = lexemUntil(RPAREN);
+    // remove parentheses
+    include.remove(0, 1);
+    include.chop(1);
+    includeFiles.append(include);
+}
+
 void Moc::parseSlotInPrivate(ClassDef *def, FunctionDef::Access access)
 {
     next(LPAREN);

src/tools/moc/moc.h

@@ -256,6 +256,7 @@ public:
     void parseInterfaces(ClassDef *def);
     void parseDeclareInterface();
     void parseDeclareMetatype();
+    void parseMocInclude();
     void parseSlotInPrivate(ClassDef *def, FunctionDef::Access access);
     void parsePrivateProperty(ClassDef *def);
 

src/tools/moc/token.h

@@ -179,6 +179,7 @@ QT_BEGIN_NAMESPACE
     F(Q_SCRIPTABLE_TOKEN) \
     F(Q_PRIVATE_PROPERTY_TOKEN) \
     F(Q_REVISION_TOKEN) \
+    F(Q_MOC_INCLUDE_TOKEN) \
     F(SPECIAL_TREATMENT_MARK) \
     F(MOC_INCLUDE_BEGIN) \
     F(MOC_INCLUDE_END) \

src/tools/moc/util/generate_keywords.cpp

@@ -243,6 +243,7 @@ static const Keyword keywords[] = {
     { "Q_SCRIPTABLE", "Q_SCRIPTABLE_TOKEN" },
     { "Q_PRIVATE_PROPERTY", "Q_PRIVATE_PROPERTY_TOKEN" },
     { "Q_REVISION", "Q_REVISION_TOKEN" },
+    { "Q_MOC_INCLUDE", "Q_MOC_INCLUDE_TOKEN" },
     { "\n", "NEWLINE" },
     { "\"", "QUOTE" },
     { "\'", "SINGLEQUOTE" },

tests/auto/tools/moc/allmocs_baseline_in.json

@@ -1012,6 +1012,65 @@
         "inputFile": "grand-parent-gadget-class.h",
         "outputRevision": 67
     },
+    {
+        "classes": [
+            {
+                "className": "TestFwdProperties",
+                "properties": [
+                    {
+                        "constant": false,
+                        "designable": true,
+                        "final": false,
+                        "name": "prop1",
+                        "read": "getProp1",
+                        "scriptable": true,
+                        "stored": true,
+                        "type": "FwdClass1",
+                        "user": false,
+                        "write": "setProp1"
+                    },
+                    {
+                        "constant": false,
+                        "designable": true,
+                        "final": false,
+                        "name": "prop2",
+                        "read": "getProp2",
+                        "scriptable": true,
+                        "stored": true,
+                        "type": "FwdClass2",
+                        "user": false,
+                        "write": "setProp2"
+                    },
+                    {
+                        "constant": false,
+                        "designable": true,
+                        "final": false,
+                        "name": "prop3",
+                        "read": "getProp3",
+                        "scriptable": true,
+                        "stored": true,
+                        "type": "FwdClass3",
+                        "user": false,
+                        "write": "setProp3"
+                    }
+                ],
+                "qualifiedClassName": "TestFwdProperties",
+                "superClasses": [
+                    {
+                        "access": "public",
+                        "name": "QObject"
+                    }
+                ]
+            },
+            {
+                "className": "SomeRandomNamespace",
+                "gadget": true,
+                "qualifiedClassName": "SomeRandomNamespace"
+            }
+        ],
+        "inputFile": "moc_include.h",
+        "outputRevision": 67
+    },
     {
         "classes": [
             {

tests/auto/tools/moc/fwdclass1.h

@@ -0,0 +1,38 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 Olivier Goffart <ogoffart@woboq.com>
+** 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifdef FWDCLASS1_H
+#error "This file can only be included once"
+#endif
+#define FWDCLASS1_H
+
+class FwdClass1
+{
+public:
+    int x;
+};

tests/auto/tools/moc/fwdclass2.h

@@ -0,0 +1,38 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 Olivier Goffart <ogoffart@woboq.com>
+** 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifdef FWDCLASS2_H
+#error "This file can only be included once"
+#endif
+#define FWDCLASS2_H
+
+class FwdClass2
+{
+public:
+    int x;
+};

tests/auto/tools/moc/fwdclass3.h

@@ -0,0 +1,38 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 Olivier Goffart <ogoffart@woboq.com>
+** 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifdef FWDCLASS3_H
+#error "This file can only be included once"
+#endif
+#define FWDCLASS3_H
+
+class FwdClass3
+{
+public:
+    int x;
+};

tests/auto/tools/moc/moc.pro

@@ -30,7 +30,8 @@ HEADERS += using-namespaces.h no-keywords.h task87883.h c-comments.h backslash-n
            related-metaobjects-in-gadget.h \
            related-metaobjects-name-conflict.h \
            namespace.h cxx17-namespaces.h \
-           cxx-attributes.h
+           cxx-attributes.h \
+           moc_include.h
 
 # No platform specifics in the JSON files, so that we can compare them
 JSON_HEADERS = $$HEADERS

tests/auto/tools/moc/moc_include.h

@@ -0,0 +1,74 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 Olivier Goffart <ogoffart@woboq.com>
+** 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 MOC_INCLUDE_H
+#define MOC_INCLUDE_H
+
+#include <QObject>
+
+class FwdClass1;
+class FwdClass2;
+class FwdClass3;
+
+Q_MOC_INCLUDE(fwdclass3.h)
+
+namespace SomeRandomNamespace {
+Q_MOC_INCLUDE("fwdclass1.h")
+Q_NAMESPACE
+}
+
+class TestFwdProperties : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(FwdClass1 prop1 WRITE setProp1 READ getProp1)
+    Q_PROPERTY(FwdClass2 prop2 WRITE setProp2 READ getProp2)
+    Q_PROPERTY(FwdClass3 prop3 WRITE setProp3 READ getProp3)
+public:
+    ~TestFwdProperties();
+
+    void setProp1(const FwdClass1 &val);
+    void setProp2(const FwdClass2 &val);
+    void setProp3(const FwdClass3 &val);
+    const FwdClass1 &getProp1() { return *prop1; }
+    const FwdClass2 &getProp2() { return *prop2; }
+    const FwdClass3 &getProp3() { return *prop3; }
+
+    QScopedPointer<FwdClass1> prop1;
+    QScopedPointer<FwdClass2> prop2;
+    QScopedPointer<FwdClass3> prop3;
+
+    Q_MOC_INCLUDE(
+        \
+        "fwdclass2.h"
+    )
+
+};
+
+Q_MOC_INCLUDE(<QString>)
+
+#endif // MOC_INCLUDE_H

tests/auto/tools/moc/tst_moc.cpp

@@ -1,7 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2016 The Qt Company Ltd.
-** Copyright (C) 2013 Olivier Goffart <ogoffart@woboq.com>
+** Copyright (C) 2020 Olivier Goffart <ogoffart@woboq.com>
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the test suite of the Qt Toolkit.
@@ -27,8 +27,6 @@
 **
 ****************************************************************************/
 
-
-
 #include <QtTest/QtTest>
 #include <stdio.h>
 #include <qobject.h>
@@ -74,6 +72,11 @@
 #include "cxx17-namespaces.h"
 #include "cxx-attributes.h"
 
+#include "moc_include.h"
+#include "fwdclass1.h"
+#include "fwdclass2.h"
+#include "fwdclass3.h"
+
 #ifdef Q_MOC_RUN
 // check that moc can parse these constructs, they are being used in Windows winsock2.h header
 #define STRING_HASH_HASH(x) ("foo" ## x ## "bar")
@@ -717,6 +720,7 @@ private slots:
     void cxx17Namespaces();
     void cxxAttributes();
     void mocJsonOutput();
+    void mocInclude();
 
 signals:
     void sigWithUnsignedArg(unsigned foo);
@@ -4002,6 +4006,29 @@ void tst_Moc::mocJsonOutput()
     QVERIFY2(actualOutput == expectedOutput, showPotentialDiff(actualOutput, expectedOutput).constData());
 }
 
+void TestFwdProperties::setProp1(const FwdClass1 &v)
+{
+    prop1.reset(new FwdClass1(v));
+}
+void TestFwdProperties::setProp2(const FwdClass2 &v)
+{
+    prop2.reset(new FwdClass2(v));
+}
+void TestFwdProperties::setProp3(const FwdClass3 &v)
+{
+    prop3.reset(new FwdClass3(v));
+}
+TestFwdProperties::~TestFwdProperties() {}
+
+Q_DECLARE_METATYPE(FwdClass1);
+
+void tst_Moc::mocInclude()
+{
+    TestFwdProperties obj;
+    obj.setProperty("prop1", QVariant::fromValue(FwdClass1 { 45 }));
+    QCOMPARE(obj.prop1->x, 45);
+}
+
 QTEST_MAIN(tst_Moc)
 
 // the generated code must compile with QT_NO_KEYWORDS