shiboken2: AbstractMetaType: use QSharedData[Pointer]

Previously, shiboken2 kept AbstractMetaType by a raw pointer. The data
were copied numerous times by AbstractMetaType::copy() when adding the
inherited functions to a AbstractMetaClass or specializing templates,
sometimes with a bool flag indicating ownership.

To get rid of the copies and ownership issues, change the type
to be based on QSharedData[Pointer]. It can then be passed
around and treated like a C++ value type, with Qt sharing the
data when possible behind the scenes.

- Extract AbstractMetaType to a separate header/source
- Remove unused AbstractMetaType::setInstantiationInCpp()
- Remove unused member m_package
- Rewrite the comparison of AbstractMetaType which
  becomes relevant for checking/detaching to do a complete
  comparison. It was previously unused, intended for
  a different implementation of view types with special cases.
- Rework debug formatting
- Invalid meta types are indicated by the "Invalid" usage pattern
  instead of null pointers

Change-Id: Ic4b1feecafb4f0355f39e178c2703b104e45cf6c
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>

1 files changed, 3 insertions, 3 deletions

diff --git a/sources/shiboken2/generator/shiboken2/overloaddata.h b/sources/shiboken2/generator/shiboken2/overloaddata.h
index 9ffb084ff..8c165a0be 100644
--- a/sources/shiboken2/generator/shiboken2/overloaddata.h
+++ b/sources/shiboken2/generator/shiboken2/overloaddata.h
@@ -52,7 +52,7 @@ public:
     int maxArgs() const { return m_headOverloadData->m_maxArgs; }
     int argPos() const { return m_argPos; }
 
-    const AbstractMetaType *argType() const { return m_argType; }
+    const AbstractMetaType &argType() const { return m_argType; }
 
     /// Returns a string list containing all the possible return types (including void) for the current OverloadData.
     QStringList returnTypes() const;
@@ -133,7 +133,7 @@ public:
 
 private:
     OverloadData(OverloadData *headOverloadData, const AbstractMetaFunction *func,
-                 const AbstractMetaType *argType, int argPos);
+                 const AbstractMetaType &argType, int argPos);
 
     void addOverload(const AbstractMetaFunction *func);
     OverloadData *addOverloadData(const AbstractMetaFunction *func, const AbstractMetaArgument *arg);
@@ -147,7 +147,7 @@ private:
     int m_minArgs;
     int m_maxArgs;
     int m_argPos;
-    const AbstractMetaType *m_argType;
+    AbstractMetaType m_argType;
     QString m_argTypeReplaced;
     MetaFunctionList m_overloads;