girepository: Add type-checking cast macros

These follow GObject conventions, using `G_TYPE_CHECK_INSTANCE_CAST` to
cast to the given type, and potentially performing some runtime checks
of the type instance’s `GType` too.

Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Fixes: #3216

girepository/giarginfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_ARG_INFO (gi_arg_info_get_type ())
 
+/**
+ * GI_ARG_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.ArgInfo] or derived pointer into a
+ * `(GIArgInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_ARG_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_ARG_INFO, GIArgInfo))
+
 /**
  * GI_IS_ARG_INFO:
  * @info: an info structure

girepository/gibaseinfo.h

@@ -50,6 +50,20 @@ typedef struct {
 
 #define GI_TYPE_BASE_INFO        (gi_base_info_get_type ())
 
+/**
+ * GI_BASE_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.BaseInfo] or derived pointer into a
+ * `(GIBaseInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_BASE_INFO(info)       (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_BASE_INFO, GIBaseInfo))
+
 /**
  * GI_IS_BASE_INFO:
  * @info: Instance to check for being a `GI_TYPE_BASE_INFO`.

girepository/giboxedinfo.h

@@ -33,6 +33,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_BOXED_INFO (gi_boxed_info_get_type ())
 
+/**
+ * GI_BOXED_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.BoxedInfo] or derived pointer into a
+ * `(GIBoxedInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_BOXED_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_BOXED_INFO, GIBoxedInfo))
+
 /**
  * GI_IS_BOXED_INFO:
  * @info: an info structure

girepository/gicallableinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_CALLABLE_INFO (gi_callable_info_get_type ())
 
+/**
+ * GI_CALLABLE_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.CallableInfo] or derived pointer into a
+ * `(GICallableInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_CALLABLE_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_CALLABLE_INFO, GICallableInfo))
+
 /**
  * GI_IS_CALLABLE_INFO:
  * @info: an info structure

girepository/gicallbackinfo.h

@@ -33,6 +33,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_CALLBACK_INFO (gi_callback_info_get_type ())
 
+/**
+ * GI_CALLBACK_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.CallbackInfo] or derived pointer into a
+ * `(GICallbackInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_CALLBACK_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_CALLBACK_INFO, GICallbackInfo))
+
 /**
  * GI_IS_CALLBACK_INFO:
  * @info: an info structure

girepository/giconstantinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_CONSTANT_INFO (gi_constant_info_get_type ())
 
+/**
+ * GI_CONSTANT_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.ConstantInfo] or derived pointer into a
+ * `(GIConstantInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_CONSTANT_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_CONSTANT_INFO, GIConstantInfo))
+
 /**
  * GI_IS_CONSTANT_INFO:
  * @info: an info structure

girepository/gienuminfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_ENUM_INFO (gi_enum_info_get_type ())
 
+/**
+ * GI_ENUM_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.EnumInfo] or derived pointer into a
+ * `(GIEnumInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_ENUM_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_ENUM_INFO, GIEnumInfo))
+
 /**
  * GI_IS_ENUM_INFO:
  * @info: an info structure

girepository/gifieldinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_FIELD_INFO (gi_field_info_get_type ())
 
+/**
+ * GI_FIELD_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.FieldInfo] or derived pointer into a
+ * `(GIFieldInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_FIELD_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_FIELD_INFO, GIFieldInfo))
+
 /**
  * GI_IS_FIELD_INFO:
  * @info: an info structure

girepository/giflagsinfo.h

@@ -33,6 +33,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_FLAGS_INFO (gi_flags_info_get_type ())
 
+/**
+ * GI_FLAGS_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.FlagsInfo] or derived pointer into a
+ * `(GIFlagsInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_FLAGS_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_FLAGS_INFO, GIFlagsInfo))
+
 /**
  * GI_IS_FLAGS_INFO:
  * @info: an info structure

girepository/gifunctioninfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_FUNCTION_INFO (gi_function_info_get_type ())
 
+/**
+ * GI_FUNCTION_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.FunctionInfo] or derived pointer into a
+ * `(GIFunctionInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_FUNCTION_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_FUNCTION_INFO, GIFunctionInfo))
+
 /**
  * GI_IS_FUNCTION_INFO:
  * @info: an info structure

girepository/giinterfaceinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_INTERFACE_INFO (gi_interface_info_get_type ())
 
+/**
+ * GI_INTERFACE_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.InterfaceInfo] or derived pointer into a
+ * `(GIInterfaceInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_INTERFACE_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_INTERFACE_INFO, GIInterfaceInfo))
+
 /**
  * GI_IS_INTERFACE_INFO:
  * @info: an info structure

girepository/giobjectinfo.h

@@ -77,6 +77,20 @@ typedef void * (*GIObjectInfoGetValueFunction) (const GValue *value);
 
 #define GI_TYPE_OBJECT_INFO (gi_object_info_get_type ())
 
+/**
+ * GI_OBJECT_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.ObjectInfo] or derived pointer into a
+ * `(GIObjectInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_OBJECT_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_OBJECT_INFO, GIObjectInfo))
+
 /**
  * GI_IS_OBJECT_INFO:
  * @info: an info structure

girepository/gipropertyinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_PROPERTY_INFO (gi_property_info_get_type ())
 
+/**
+ * GI_PROPERTY_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.PropertyInfo] or derived pointer into a
+ * `(GIPropertyInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_PROPERTY_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_PROPERTY_INFO, GIPropertyInfo))
+
 /**
  * GI_IS_PROPERTY_INFO:
  * @info: an info structure

girepository/giregisteredtypeinfo.h

@@ -35,6 +35,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_REGISTERED_TYPE_INFO (gi_registered_type_info_get_type ())
 
+/**
+ * GI_REGISTERED_TYPE_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.RegisteredTypeInfo] or derived pointer into a
+ * `(GIRegisteredTypeInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_REGISTERED_TYPE_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_REGISTERED_TYPE_INFO, GIRegisteredTypeInfo))
+
 /**
  * GI_IS_REGISTERED_TYPE_INFO:
  * @info: an info structure

girepository/gisignalinfo.h

@@ -35,6 +35,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_SIGNAL_INFO (gi_signal_info_get_type ())
 
+/**
+ * GI_SIGNAL_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.SignalInfo] or derived pointer into a
+ * `(GISignalInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_SIGNAL_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_SIGNAL_INFO, GISignalInfo))
+
 /**
  * GI_IS_SIGNAL_INFO:
  * @info: an info structure

girepository/gistructinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_STRUCT_INFO (gi_struct_info_get_type ())
 
+/**
+ * GI_STRUCT_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.StructInfo] or derived pointer into a
+ * `(GIStructInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_STRUCT_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_STRUCT_INFO, GIStructInfo))
+
 /**
  * GI_IS_STRUCT_INFO:
  * @info: an info structure

girepository/gitypeinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_TYPE_INFO (gi_type_info_get_type ())
 
+/**
+ * GI_TYPE_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.TypeInfo] or derived pointer into a
+ * `(GITypeInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_TYPE_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_TYPE_INFO, GITypeInfo))
+
 /**
  * GI_IS_TYPE_INFO:
  * @info: an info structure

girepository/giunioninfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_UNION_INFO (gi_union_info_get_type ())
 
+/**
+ * GI_UNION_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.UnionInfo] or derived pointer into a
+ * `(GIUnionInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_UNION_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_UNION_INFO, GIUnionInfo))
+
 /**
  * GI_IS_UNION_INFO:
  * @info: an info structure

girepository/giunresolvedinfo.h

@@ -33,6 +33,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_UNRESOLVED_INFO (gi_unresolved_info_get_type ())
 
+/**
+ * GI_UNRESOLVED_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.UnresolvedInfo] or derived pointer into a
+ * `(GIUnresolvedInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_UNRESOLVED_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_UNRESOLVED_INFO, GIUnresolvedInfo))
+
 /**
  * GI_IS_UNRESOLVED_INFO:
  * @info: an info structure

girepository/givalueinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_VALUE_INFO (gi_value_info_get_type ())
 
+/**
+ * GI_VALUE_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.ValueInfo] or derived pointer into a
+ * `(GIValueInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_VALUE_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_VALUE_INFO, GIValueInfo))
+
 /**
  * GI_IS_VALUE_INFO:
  * @info: an info structure

girepository/givfuncinfo.h

@@ -34,6 +34,20 @@ G_BEGIN_DECLS
 
 #define GI_TYPE_VFUNC_INFO (gi_vfunc_info_get_type ())
 
+/**
+ * GI_VFUNC_INFO:
+ * @info: Info object which is subject to casting.
+ *
+ * Casts a [type@GIRepository.VFuncInfo] or derived pointer into a
+ * `(GIVFuncInfo*)` pointer.
+ *
+ * Depending on the current debugging level, this function may invoke
+ * certain runtime checks to identify invalid casts.
+ *
+ * Since: 2.80
+ */
+#define GI_VFUNC_INFO(info) (G_TYPE_CHECK_INSTANCE_CAST ((info), GI_TYPE_VFUNC_INFO, GIVFuncInfo))
+
 /**
  * GI_IS_VFUNC_INFO:
  * @info: an info structure