Multiple build errors in src/sampleplugin.h: Undefined interface & expected class-name before ‘,’ token

[swiss-knight]

Bug description
The compilation from source stops on the following error:

src/sampleplugin.h:37:1: error: Undefined interface
make[2]: *** [Makefile:399: moc/moc_sampleplugin.cpp] Error 1
make[2]: *** Waiting for unfinished jobs....
In file included from src/sampleplugin.cpp:19:
src/sampleplugin.h:30:35: error: expected class-name before ‘,’ token

See full stack hereunder.

How to reproduce

cd /opt \
&& git clone https://github.com/pgmodeler/pgmodeler.git \
&& cd pgmodeler \
&& pkg-config libxml-2.0 --cflags --libs \
&& pkg-config libpq --cflags --libs \
&& $QT_ROOT/bin/qmake6 -r CONFIG+=release PREFIX=$INSTALLATION_ROOT BINDIR=$INSTALLATION_ROOT \
   PRIVATEBINDIR=$INSTALLATION_ROOT PRIVATELIBDIR=$INSTALLATION_ROOT/lib pgmodeler.pro \
&& make clean \
&& make -j4

Expected behavior
The compilation runs to the end without errors.

Screenshots
N/A.

Info about your desktop

• OS: Ubuntu 22.04.4 LTS (6.5.0-18-generic x86_64 GNU/Linu)
• Shell: bash 5.1.16
• DE: GNOME 42.9
• WM: Mutter
• WM Theme: Adwaita
• pgModeler version: main branch
• Qt version:

$ qmake6 -v
QMake version 3.1
Using Qt version 6.2.4 in /usr/lib/x86_64-linux-gnu

Stacktrace / Debug info
If pgModeler crashed after the bug raised attach the stacktrace below

src/sampleplugin.h:37:1: error: Undefined interface
make[2]: *** [Makefile:399: moc/moc_sampleplugin.cpp] Error 1
make[2]: *** Waiting for unfinished jobs....
In file included from src/sampleplugin.cpp:19:
src/sampleplugin.h:30:35: error: expected class-name before ‘,’ token
   30 | class SamplePlugin: public QObject, public PgModelerPlugin {
      |                                   ^
In file included from /usr/include/x86_64-linux-gnu/qt6/QtCore/qnamespace.h:45,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qbytearray.h:45,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qstringview.h:58,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qchar.h:666,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qstring.h:50,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/QString:1,
                 from ../../libs/libutils/src/pgmodelerplugin.h:29,
                 from src/sampleplugin.h:28,
                 from src/sampleplugin.cpp:19:
/usr/include/x86_64-linux-gnu/qt6/QtCore/qtmetamacros.h:165:29: error: ‘QMetaObject::Call’ has not been declared
  165 |     virtual int qt_metacall(QMetaObject::Call, int, void **); \
      |                             ^~~~~~~~~~~
src/sampleplugin.h:32:17: note: in expansion of macro ‘Q_OBJECT’
   32 |                 Q_OBJECT
      |                 ^~~~~~~~
/usr/include/x86_64-linux-gnu/qt6/QtCore/qtmetamacros.h:169:66: error: ‘QObject’ has not been declared
  169 |     Q_DECL_HIDDEN_STATIC_METACALL static void qt_static_metacall(QObject *, QMetaObject::Call, int, void **); \
      |                                                                  ^~~~~~~
src/sampleplugin.h:32:17: note: in expansion of macro ‘Q_OBJECT’
   32 |                 Q_OBJECT
      |                 ^~~~~~~~
/usr/include/x86_64-linux-gnu/qt6/QtCore/qtmetamacros.h:169:77: error: ‘QMetaObject::Call’ has not been declared
  169 |     Q_DECL_HIDDEN_STATIC_METACALL static void qt_static_metacall(QObject *, QMetaObject::Call, int, void **); \
      |                                                                             ^~~~~~~~~~~
src/sampleplugin.h:32:17: note: in expansion of macro ‘Q_OBJECT’
   32 |                 Q_OBJECT
      |                 ^~~~~~~~
In file included from src/sampleplugin.cpp:19:
src/sampleplugin.h:39:17: error: ‘QAction’ does not name a type
   39 |                 QAction *config_action, *toolbar_action, *model_action;
      |                 ^~~~~~~
src/sampleplugin.h:41:17: error: ‘QToolButton’ does not name a type
   41 |                 QToolButton *dbexplorer_tb;
      |                 ^~~~~~~~~~~
src/sampleplugin.h:43:33: error: ‘MainWindow’ has not been declared
   43 |                 void initPlugin(MainWindow *main_wnd) override;
      |                                 ^~~~~~~~~~
src/sampleplugin.h:54:17: error: ‘QAction’ does not name a type
   54 |                 QAction *getAction(ActionId act_id) const override;
      |                 ^~~~~~~
src/sampleplugin.h:55:17: error: ‘QToolButton’ does not name a type
   55 |                 QToolButton *getToolButton() const override;
      |                 ^~~~~~~~~~~
src/sampleplugin.h:43:22: error: ‘void SamplePlugin::initPlugin(int*)’ marked ‘override’, but does not override
   43 |                 void initPlugin(MainWindow *main_wnd) override;
      |                      ^~~~~~~~~~
src/sampleplugin.h:49:25: error: ‘QString SamplePlugin::getPluginTitle() const’ marked ‘override’, but does not override
   49 |                 QString getPluginTitle() const override;
      |                         ^~~~~~~~~~~~~~
src/sampleplugin.h:50:25: error: ‘QString SamplePlugin::getPluginVersion() const’ marked ‘override’, but does not override
   50 |                 QString getPluginVersion() const override;
      |                         ^~~~~~~~~~~~~~~~
src/sampleplugin.h:51:25: error: ‘QString SamplePlugin::getPluginAuthor() const’ marked ‘override’, but does not override
   51 |                 QString getPluginAuthor() const override;
      |                         ^~~~~~~~~~~~~~~
src/sampleplugin.h:52:25: error: ‘QString SamplePlugin::getPluginDescription() const’ marked ‘override’, but does not override
   52 |                 QString getPluginDescription() const override;
      |                         ^~~~~~~~~~~~~~~~~~~~
src/sampleplugin.h:58:22: error: ‘void SamplePlugin::showPluginInfo() const’ marked ‘override’, but does not override
   58 |                 void showPluginInfo(void) const override;
      |                      ^~~~~~~~~~~~~~
In file included from /usr/include/x86_64-linux-gnu/qt6/QtCore/qnamespace.h:45,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qbytearray.h:45,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qstringview.h:58,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qchar.h:666,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qstring.h:50,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/QString:1,
                 from ../../libs/libutils/src/pgmodelerplugin.h:29,
                 from src/sampleplugin.h:28,
                 from src/sampleplugin.cpp:19:
src/sampleplugin.h: In static member function ‘static QString SamplePlugin::tr(const char*, const char*, int)’:
/usr/include/x86_64-linux-gnu/qt6/QtCore/qtmetamacros.h:162:30: error: ‘SamplePlugin::staticMetaObject’ has incomplete type
  162 |     static const QMetaObject staticMetaObject; \
      |                              ^~~~~~~~~~~~~~~~
src/sampleplugin.h:32:17: note: in expansion of macro ‘Q_OBJECT’
   32 |                 Q_OBJECT
      |                 ^~~~~~~~
In file included from /usr/include/x86_64-linux-gnu/qt6/QtCore/qbytearray.h:45,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qstringview.h:58,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qchar.h:666,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/qstring.h:50,
                 from /usr/include/x86_64-linux-gnu/qt6/QtCore/QString:1,
                 from ../../libs/libutils/src/pgmodelerplugin.h:29,
                 from src/sampleplugin.h:28,
                 from src/sampleplugin.cpp:19:
/usr/include/x86_64-linux-gnu/qt6/QtCore/qnamespace.h:53:8: note: forward declaration of ‘struct QMetaObject’
   53 | struct QMetaObject;
      |        ^~~~~~~~~~~
src/sampleplugin.cpp: In constructor ‘SamplePlugin::SamplePlugin()’:
src/sampleplugin.cpp:26:9: error: ‘configurePluginInfo’ was not declared in this scope
   26 |         configurePluginInfo(getPluginTitle(),
      |         ^~~~~~~~~~~~~~~~~~~
src/sampleplugin.cpp:31:9: error: ‘config_action’ was not declared in this scope; did you mean ‘sigaction’?
   31 |         config_action = nullptr;
      |         ^~~~~~~~~~~~~
      |         sigaction
src/sampleplugin.cpp:32:9: error: ‘toolbar_action’ was not declared in this scope
   32 |         toolbar_action = nullptr;
      |         ^~~~~~~~~~~~~~
src/sampleplugin.cpp:33:9: error: ‘model_action’ was not declared in this scope
   33 |         model_action = nullptr;
      |         ^~~~~~~~~~~~
src/sampleplugin.cpp:34:9: error: ‘dbexplorer_tb’ was not declared in this scope
   34 |         dbexplorer_tb = nullptr;
      |         ^~~~~~~~~~~~~
src/sampleplugin.cpp: In destructor ‘virtual SamplePlugin::~SamplePlugin()’:
src/sampleplugin.cpp:39:16: error: ‘dbexplorer_tb’ was not declared in this scope
   39 |         delete dbexplorer_tb;
      |                ^~~~~~~~~~~~~
src/sampleplugin.cpp: At global scope:
src/sampleplugin.cpp:42:6: error: no declaration matches ‘void SamplePlugin::initPlugin(MainWindow*)’
   42 | void SamplePlugin::initPlugin(MainWindow *main_wnd)
      |      ^~~~~~~~~~~~
In file included from src/sampleplugin.cpp:19:
src/sampleplugin.h:43:22: note: candidate is: ‘void SamplePlugin::initPlugin(int*)’
   43 |                 void initPlugin(MainWindow *main_wnd) override;
      |                      ^~~~~~~~~~
src/sampleplugin.h:30:7: note: ‘class SamplePlugin’ defined here
   30 | class SamplePlugin: public QObject, public PgModelerPlugin {
      |       ^~~~~~~~~~~~
src/sampleplugin.cpp: In member function ‘void SamplePlugin::showPluginInfo() const’:
src/sampleplugin.cpp:83:9: error: ‘plugin_info_frm’ was not declared in this scope
   83 |         plugin_info_frm->show();
      |         ^~~~~~~~~~~~~~~
src/sampleplugin.cpp: At global scope:
src/sampleplugin.cpp:118:10: error: ‘QAction* SamplePlugin::getAction’ is not a static data member of ‘class SamplePlugin’
  118 | QAction *SamplePlugin::getAction(ActionId act_id) const
      |          ^~~~~~~~~~~~
src/sampleplugin.cpp:118:34: error: ‘ActionId’ was not declared in this scope
  118 | QAction *SamplePlugin::getAction(ActionId act_id) const
      |                                  ^~~~~~~~
src/sampleplugin.cpp:129:14: error: no declaration matches ‘QToolButton* SamplePlugin::getToolButton() const’
  129 | QToolButton *SamplePlugin::getToolButton() const
      |              ^~~~~~~~~~~~
src/sampleplugin.cpp:129:14: note: no functions named ‘QToolButton* SamplePlugin::getToolButton() const’
In file included from src/sampleplugin.cpp:19:
src/sampleplugin.h:30:7: note: ‘class SamplePlugin’ defined here
   30 | class SamplePlugin: public QObject, public PgModelerPlugin {
      |       ^~~~~~~~~~~~
make[2]: *** [Makefile:579: obj/sampleplugin.o] Error 1
make[2]: Leaving directory '/opt/pgmodeler/plugins/sampleplugin'
make[1]: *** [Makefile:47: sub-sampleplugin-make_first-ordered] Error 2
make[1]: Leaving directory '/opt/pgmodeler/plugins'
make: *** [Makefile:531: sub-plugins-make_first-ordered] Error 2

Additional info:

There are two glitches in the documentation : https://www.pgmodeler.io/support/installation

1. The following commands doesn't work and should be rewritten using libxml­-2.0 instead (notice the dash):

$ pkg-config libxml­2.0 --cflags --libs
Package libxml­2.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libxml­2.0.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libxml­2.0' foun

2. The usage of the qmake6 command on OS where qmake is pointing to qmake 5.