Fix GObject and GValue CType guessing

For some signals, their parameter types don't have CType fields, and
when we try to guess them, the guessed CType values would be missing a
pointer, causing issue #107 to happen. This commit fixes that.

Fixes #107

Author: diamondburned

gir/girgen/types/resolve.go

@@ -793,7 +793,12 @@ func Resolve(gen FileGenerator, typ gir.Type) *Resolved {
 	var result *gir.TypeFindResult
 
 	// Try and dig out the CType if we have none.
+	//
+	// This doesn't always work though, so we'll record if we had an empty CType
+	// so we can fix it later if we have to.
+	var hadEmptyCType bool
 	if typ.CType == "" {
+		hadEmptyCType = true
 		if result = Find(gen, typ.Name); result != nil {
 			typ.CType = result.CType()
 		}
@@ -829,6 +834,19 @@ func Resolve(gen FileGenerator, typ gir.Type) *Resolved {
 	// Fill namespace.
 	typ.Name = EnsureNamespace(gen.Namespace(), typ.Name)
 
+	// In some cases, the gir.Type doesn't have a CType, and when we fill in
+	// our own, we wouldn't know if it's a pointer or not. Try to keep this
+	// consistent.
+	//
+	// Particularly, we want to do this for issue #107. This also happens in
+	// multiple other places though.
+	switch typ.Name {
+	case "GObject.Object", "GObject.Value", "GValue":
+		if hadEmptyCType {
+			typ.CType += "*"
+		}
+	}
+
 	// Resolve the unknown namespace that is GLib and primitive types.
 	switch typ.Name {
 	// TODO: ignore field

pkg/gio/v2/gio.go

@@ -861,7 +861,7 @@ import (
 // extern gboolean _gotk4_gtk3_TickCallback(GtkWidget*, GdkFrameClock*, gpointer);
 // extern gboolean _gotk4_gtk3_TextView_ConnectExtendSelection(gpointer, GtkTextExtendSelection, GtkTextIter*, GtkTextIter*, GtkTextIter*, guintptr);
 // extern gboolean _gotk4_gtk3_TextViewClass_extend_selection(GtkTextView*, GtkTextExtendSelection, GtkTextIter*, GtkTextIter*, GtkTextIter*);
-// extern gboolean _gotk4_gtk3_TextTag_ConnectEvent(gpointer, GObject, GdkEvent, GtkTextIter*, guintptr);
+// extern gboolean _gotk4_gtk3_TextTag_ConnectEvent(gpointer, GObject*, GdkEvent, GtkTextIter*, guintptr);
 // extern gboolean _gotk4_gtk3_TextTagClass_event(GtkTextTag*, GObject*, GdkEvent*, GtkTextIter*);
 // extern gboolean _gotk4_gtk3_TextCharPredicate(gunichar, gpointer);
 // extern gboolean _gotk4_gtk3_Switch_ConnectStateSet(gpointer, gboolean, guintptr);
@@ -951,7 +951,7 @@ import (
 // extern gboolean _gotk4_gtk3_CellAreaClass_focus(GtkCellArea*, GtkDirectionType);
 // extern gboolean _gotk4_gtk3_CellAreaClass_activate(GtkCellArea*, GtkCellAreaContext*, GtkWidget*, GdkRectangle*, GtkCellRendererState, gboolean);
 // extern gboolean _gotk4_gtk3_CellAllocCallback(GtkCellRenderer*, GdkRectangle*, GdkRectangle*, gpointer);
-// extern gboolean _gotk4_gtk3_AccelGroup_ConnectAccelActivate(gpointer, GObject, guint, GdkModifierType, guintptr);
+// extern gboolean _gotk4_gtk3_AccelGroup_ConnectAccelActivate(gpointer, GObject*, guint, GdkModifierType, guintptr);
 // extern gboolean _gotk4_gtk3_AboutDialog_ConnectActivateLink(gpointer, gchar*, guintptr);
 // extern gboolean _gotk4_gtk3_AboutDialogClass_activate_link(GtkAboutDialog*, gchar*);
 // extern GtkWidgetPath* _gotk4_gtk3_ContainerClass_get_path_for_child(GtkContainer*, GtkWidget*);
@@ -975,7 +975,7 @@ import (
 // extern GdkGLContext* _gotk4_gtk3_GLArea_ConnectCreateContext(gpointer, guintptr);
 // extern GType _gotk4_gtk3_ContainerClass_child_type(GtkContainer*);
 // extern GType _gotk4_gtk3_BuilderClass_get_type_from_name(GtkBuilder*, char*);
-// extern GObject _gotk4_gtk3_PrintOperation_ConnectCreateCustomWidget(gpointer, guintptr);
+// extern GObject* _gotk4_gtk3_PrintOperation_ConnectCreateCustomWidget(gpointer, guintptr);
 // extern AtkObject* _gotk4_gtk3_WidgetClass_get_accessible(GtkWidget*);
 // AtkObject* _gotk4_gtk3_Widget_virtual_get_accessible(void* fnptr, GtkWidget* arg0) {
 //   return ((AtkObject* (*)(GtkWidget*))(fnptr))(arg0);