Generate an instance with KSharedConfig::Ptr for singleton and arg

Summary:
In case a kcfg with arg="true" was used and singleton the static
instance method only accepted a QString config name. This made it
impossible to combine a singleton config with an already existing and
open KSharedConfig::Ptr.

With this change an overloaded instance method is added which takes a
KSharedConfig::Ptr as argument. The private ctor, though, only takes a
KSharedConfig::Ptr and the instance method taking a QString argument
uses KSharedConfig::openConfig on the config file name.

The change is source-incompatible in the following situation:
* kcfgfile arg="true"
* Singleton = true
* Inherits is specified

In this situation the previous revision created an instance method with
a QString argument and passed that to the parent constructor. This is
not in accordance with the documentation. Any user of this behavior was
relying on a bug. With this change now the call to the parent
constructor carries a KSharedConfigPtr.

Test Plan:
kconfigcompiler tests still pass and a config with singleton
and arg="true" generates the code as I need it

Reviewers: #frameworks, dfaure, mdawson

Differential Revision: https://phabricator.kde.org/D3690

8 files changed, 183 insertions, 11 deletions

diff --git a/autotests/kconfig_compiler/CMakeLists.txt b/autotests/kconfig_compiler/CMakeLists.txt
index 0971471b..590c7700 100644
--- a/autotests/kconfig_compiler/CMakeLists.txt
+++ b/autotests/kconfig_compiler/CMakeLists.txt
@@ -112,6 +112,7 @@ set(test8_SRCS test8main.cpp )
 
 gen_kcfg_test_source(test8a test8_SRCS)
 gen_kcfg_test_source(test8b test8_SRCS)
+gen_kcfg_test_source(test8c test8_SRCS)
 
 ecm_add_test(TEST_NAME test8 ${test8_SRCS})
 target_link_libraries(test8 KF5::ConfigGui)
diff --git a/autotests/kconfig_compiler/kconfigcompiler_test.cpp b/autotests/kconfig_compiler/kconfigcompiler_test.cpp
index 88b462ef..01efd602 100644
--- a/autotests/kconfig_compiler/kconfigcompiler_test.cpp
+++ b/autotests/kconfig_compiler/kconfigcompiler_test.cpp
@@ -38,6 +38,7 @@ static CompilerTestSet testCases = {
     "test7.cpp", "test7.h",
     "test8a.cpp", "test8a.h",
     "test8b.cpp", "test8b.h",
+    "test8c.cpp", "test8c.h",
     "test9.h", "test9.cpp",
     "test10.h", "test10.cpp",
     "test11.h", "test11.cpp",
diff --git a/autotests/kconfig_compiler/test8c.cpp.ref b/autotests/kconfig_compiler/test8c.cpp.ref
new file mode 100644
index 00000000..90305c1f
--- /dev/null
+++ b/autotests/kconfig_compiler/test8c.cpp.ref
@@ -0,0 +1,65 @@
+// This file is generated by kconfig_compiler_kf5 from test8c.kcfg.
+// All changes you do to this file will be lost.
+
+#include "test8c.h"
+
+#include <qglobal.h>
+#include <QtCore/QFile>
+
+#include <QDebug>
+
+class Test8cHelper
+{
+  public:
+    Test8cHelper() : q(0) {}
+    ~Test8cHelper() { delete q; }
+    Test8c *q;
+};
+Q_GLOBAL_STATIC(Test8cHelper, s_globalTest8c)
+Test8c *Test8c::self()
+{
+  if (!s_globalTest8c()->q)
+     qFatal("you need to call Test8c::instance before using");
+  return s_globalTest8c()->q;
+}
+
+void Test8c::instance(const QString& cfgfilename)
+{
+  if (s_globalTest8c()->q) {
+     qDebug() << "Test8c::instance called after the first use - ignoring";
+     return;
+  }
+  new Test8c(KSharedConfig::openConfig(cfgfilename));
+  s_globalTest8c()->q->read();
+}
+
+void Test8c::instance(KSharedConfig::Ptr config)
+{
+  if (s_globalTest8c()->q) {
+     qDebug() << "Test8c::instance called after the first use - ignoring";
+     return;
+  }
+  new Test8c(config);
+  s_globalTest8c()->q->read();
+}
+
+Test8c::Test8c(  KSharedConfig::Ptr config  )
+  : KConfigSkeleton( config )
+{
+  Q_ASSERT(!s_globalTest8c()->q);
+  s_globalTest8c()->q = this;
+  setCurrentGroup( QStringLiteral( "Group" ) );
+
+  KConfigSkeleton::ItemFont  *itemFont;
+  itemFont = new KConfigSkeleton::ItemFont( currentGroup(), QStringLiteral( "Font" ), mFont, QFont() );
+  addItem( itemFont, QStringLiteral( "Font" ) );
+  KConfigSkeleton::ItemFont  *itemTitleFont;
+  itemTitleFont = new KConfigSkeleton::ItemFont( currentGroup(), QStringLiteral( "TitleFont" ), mTitleFont, QFont() );
+  addItem( itemTitleFont, QStringLiteral( "TitleFont" ) );
+}
+
+Test8c::~Test8c()
+{
+  s_globalTest8c()->q = 0;
+}
+
diff --git a/autotests/kconfig_compiler/test8c.h.ref b/autotests/kconfig_compiler/test8c.h.ref
new file mode 100644
index 00000000..8ed9962c
--- /dev/null
+++ b/autotests/kconfig_compiler/test8c.h.ref
@@ -0,0 +1,70 @@
+// This file is generated by kconfig_compiler_kf5 from test8c.kcfg.
+// All changes you do to this file will be lost.
+#ifndef TEST8C_H
+#define TEST8C_H
+
+#include <kconfigskeleton.h>
+#include <QCoreApplication>
+#include <QDebug>
+
+class Test8c : public KConfigSkeleton
+{
+  public:
+
+    static Test8c *self();
+    static void instance(const QString& cfgfilename);
+    static void instance(KSharedConfig::Ptr config);
+    ~Test8c();
+
+    /**
+      Set Font
+    */
+    static
+    void setFont( const QFont & v )
+    {
+      if (!self()->isImmutable( QStringLiteral( "Font" ) ))
+        self()->mFont = v;
+    }
+
+    /**
+      Get Font
+    */
+    static
+    QFont font()
+    {
+      return self()->mFont;
+    }
+
+    /**
+      Set TitleFont
+    */
+    static
+    void setTitleFont( const QFont & v )
+    {
+      if (!self()->isImmutable( QStringLiteral( "TitleFont" ) ))
+        self()->mTitleFont = v;
+    }
+
+    /**
+      Get TitleFont
+    */
+    static
+    QFont titleFont()
+    {
+      return self()->mTitleFont;
+    }
+
+  protected:
+    Test8c(KSharedConfig::Ptr config);
+    friend class Test8cHelper;
+
+
+    // Group
+    QFont mFont;
+    QFont mTitleFont;
+
+  private:
+};
+
+#endif
+
diff --git a/autotests/kconfig_compiler/test8c.kcfg b/autotests/kconfig_compiler/test8c.kcfg
new file mode 100644
index 00000000..24038a69
--- /dev/null
+++ b/autotests/kconfig_compiler/test8c.kcfg
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<kcfg xmlns="http://www.kde.org/standards/kcfg/1.0"
+      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+      xsi:schemaLocation="http://www.kde.org/standards/kcfg/1.0
+      http://www.kde.org/standards/kcfg/1.0/kcfg.xsd" >
+  <kcfgfile arg="true"/>
+
+  <group name="Group">
+    <entry name="Font" type="Font">
+      <default code="true">QFont()</default>
+    </entry>
+
+    <entry name="TitleFont" type="Font">
+      <default code="true">QFont()</default>
+    </entry>
+  </group>
+</kcfg>
diff --git a/autotests/kconfig_compiler/test8c.kcfgc b/autotests/kconfig_compiler/test8c.kcfgc
new file mode 100644
index 00000000..e53e5a04
--- /dev/null
+++ b/autotests/kconfig_compiler/test8c.kcfgc
@@ -0,0 +1,4 @@
+File=test8c.kcfg
+ClassName=Test8c
+Mutators=true
+Singleton=true
diff --git a/autotests/kconfig_compiler/test8main.cpp b/autotests/kconfig_compiler/test8main.cpp
index b8fcc492..9843df72 100644
--- a/autotests/kconfig_compiler/test8main.cpp
+++ b/autotests/kconfig_compiler/test8main.cpp
@@ -21,6 +21,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include "test8a.h"
 #include "test8b.h"
+#include "test8c.h"
 #include <QGuiApplication>
 
 int main(int argc, char **argv)
@@ -30,6 +31,8 @@ int main(int argc, char **argv)
     Test8a *config1 = new Test8a(KSharedConfig::openConfig(QString()));
     Test8a *config2 = new Test8a();
     Test8b::self();
+    Test8c::instance(KSharedConfig::openConfig(QString()));
+    Test8c::self();
     delete config1;
     delete config2;
     return 0;
diff --git a/src/kconfig_compiler/kconfig_compiler.cpp b/src/kconfig_compiler/kconfig_compiler.cpp
index 5c3f478f..c836252f 100644
--- a/src/kconfig_compiler/kconfig_compiler.cpp
+++ b/src/kconfig_compiler/kconfig_compiler.cpp
@@ -1893,6 +1893,7 @@ int main(int argc, char **argv)
         h << "    static " << cfg.className << " *self();" << endl;
         if (cfgFileNameArg) {
             h << "    static void instance(const QString& cfgfilename);" << endl;
+            h << "    static void instance(KSharedConfig::Ptr config);" << endl;
         }
     }
 
@@ -2115,7 +2116,7 @@ int main(int argc, char **argv)
     if (cfg.singleton) {
         h << "    " << cfg.className << "(";
         if (cfgFileNameArg) {
-            h << "const QString& arg";
+            h << "KSharedConfig::Ptr config";
         }
         h << ");" << endl;
         h << "    friend class " << cfg.className << "Helper;" << endl << endl;
@@ -2320,15 +2321,25 @@ int main(int argc, char **argv)
         cpp << "}" << endl << endl;
 
         if (cfgFileNameArg) {
-            cpp << "void " << cfg.className << "::instance(const QString& cfgfilename)" << endl;
-            cpp << "{" << endl;
-            cpp << "  if (s_global" << cfg.className << "()->q) {" << endl;
-            cpp << "     qDebug() << \"" << cfg.className << "::instance called after the first use - ignoring\";" << endl;
-            cpp << "     return;" << endl;
-            cpp << "  }" << endl;
-            cpp << "  new " << cfg.className << "(cfgfilename);" << endl;
-            cpp << "  s_global" << cfg.className << "()->q->read();" << endl;
-            cpp << "}" << endl << endl;
+            auto instance = [&cfg, &cpp] (const QString &type, const QString arg, bool wrap) {
+                cpp << "void " << cfg.className << "::instance(" << type << " " << arg << ")" << endl;
+                cpp << "{" << endl;
+                cpp << "  if (s_global" << cfg.className << "()->q) {" << endl;
+                cpp << "     qDebug() << \"" << cfg.className << "::instance called after the first use - ignoring\";" << endl;
+                cpp << "     return;" << endl;
+                cpp << "  }" << endl;
+                cpp << "  new " << cfg.className << "(";
+                if (wrap) {
+                    cpp << "KSharedConfig::openConfig(" << arg << ")";
+                } else {
+                    cpp << arg;
+                }
+                cpp << ");" << endl;
+                cpp << "  s_global" << cfg.className << "()->q->read();" << endl;
+                cpp << "}" << endl << endl;
+            };
+            instance(QStringLiteral("const QString&"), QStringLiteral("cfgfilename"), true);
+            instance(QStringLiteral("KSharedConfig::Ptr"), QStringLiteral("config"), false);
         }
     }
 
@@ -2339,7 +2350,7 @@ int main(int argc, char **argv)
     // Constructor
     cpp << cfg.className << "::" << cfg.className << "( ";
     if (cfgFileNameArg) {
-        if (!cfg.singleton && ! cfg.forceStringFilename) {
+        if (! cfg.forceStringFilename) {
             cpp << " KSharedConfig::Ptr config";
         } else {
             cpp << " const QString& config";