libgee-0.8: undefined constant LibGee::FutureMapFunc

[aljelly]

After the fix for #31, I tried building libgee again in the same way:

require_gobject("Gee")

Results in:

There was a problem expanding macro 'require_gobject'

Code in src/gtk-test.cr:5:1

 5 | require_gobject("Gee")
     ^
Called macro defined in lib/gobject/src/gobject.cr:7:1

 7 | macro require_gobject(namespace)

Which expanded to:

 > 899 | fun future_wait_async = gee_future_wait_async(this : Future*, _callback : LibGio::AsyncReadyCallback, _callback__target : Void*) : Void
 > 900 | fun future_wait_finish = gee_future_wait_finish(this : Future*, _res : LibGio::AsyncResult*, error : LibGLib::Error**) : Void*
 > 901 | fun future_map = gee_future_map(this : Future*, a_type : UInt64, a_dup_func : LibGObject::BoxedCopyFunc, a_destroy_func : LibGLib::DestroyNotify, func : LibGee::FutureMapFunc, func_target : Void*, func_target_destroy_notify : LibGLib::DestroyNotify) : LibGee::Future*
                                                                                                                                                                  ^--------------------
Error: undefined constant LibGee::FutureMapFunc

Context (from error trace):

 >  867 |   struct Future # interface
 >  868 |     parent_iface : LibGObject::TypeInterface
 >  869 |     wait : -> Void
 >  870 |     wait_until : -> Void
 >  871 |     wait_async : -> Void
 >  872 |     wait_finish : -> Void
 >  873 |     map : -> Void
 >  874 |     light_map : -> Void
 >  875 |     light_map_broken : -> Void
 >  876 |     zip : -> Void
 >  877 |     flat_map : -> Void
 >  878 |     get_value : -> Void
 >  879 |     get_ready : -> Void
 >  880 |     get_exception : -> Void
 >  881 |   # Requires Object
 >  882 |     # Virtual function wait
 >  883 |     # Virtual function wait_until
 >  884 |     # Virtual function wait_async
 >  885 |     # Virtual function wait_finish
 >  886 |     # Virtual function map
 >  887 |     # Virtual function light_map
 >  888 |     # Virtual function light_map_broken
 >  889 |     # Virtual function zip
 >  890 |     # Virtual function flat_map
 >  891 |     # Virtual function get_value
 >  892 |     # Virtual function get_ready
 >  893 |     # Virtual function get_exception
 >  894 |     # Property ready : Bool
 >  895 |     # Property exception : LibGLib::Error**
 >  896 |   end
 >  897 |   fun future_wait = gee_future_wait(this : Future*, error : LibGLib::Error**) : Void*
 >  898 |   fun future_wait_until = gee_future_wait_until(this : Future*, end_time : Int64, value : Void**, error : LibGLib::Error**) : Bool
 >  899 |   fun future_wait_async = gee_future_wait_async(this : Future*, _callback : LibGio::AsyncReadyCallback, _callback__target : Void*) : Void
 >  900 |   fun future_wait_finish = gee_future_wait_finish(this : Future*, _res : LibGio::AsyncResult*, error : LibGLib::Error**) : Void*
 >  901 |   # line causing error below
 >  901 |   fun future_map = gee_future_map(this : Future*, a_type : UInt64, a_dup_func : LibGObject::BoxedCopyFunc, a_destroy_func : LibGLib::DestroyNotify, func : LibGee::FutureMapFunc, func_target : Void*, func_target_destroy_notify : LibGLib::DestroyNotify) : LibGee::Future*
 >  902 |   fun future_light_map = gee_future_light_map_fixed(this : Future*, a_type : UInt64, a_dup_func : LibGObject::BoxedCopyFunc, a_destroy_func : LibGLib::DestroyNotify, func : LibGee::FutureLightMapFunc, func_target : Void*, func_target_destroy_notify : LibGLib::DestroyNotify) : LibGee::Future*
 >  903 |   fun future_light_map_broken = gee_future_light_map(this : Future*, a_type : UInt64, a_dup_func : LibGObject::BoxedCopyFunc, a_destroy_func : LibGLib::DestroyNotify, func : LibGee::FutureLightMapFunc, func_target : Void*) : LibGee::Future*
 >  904 |   fun future_zip = gee_future_zip(this : Future*, a_type : UInt64, a_dup_func : LibGObject::BoxedCopyFunc, a_destroy_func : LibGLib::DestroyNotify, b_type : UInt64, b_dup_func : LibGObject::BoxedCopyFunc, b_destroy_func : LibGLib::DestroyNotify, zip_func : LibGee::FutureZipFunc, zip_func_target : Void*, second : LibGee::Future*) : LibGee::Future*
 >  905 |   fun future_flat_map = gee_future_flat_map(this : Future*, a_type : UInt64, a_dup_func : LibGObject::BoxedCopyFunc, a_destroy_func : LibGLib::DestroyNotify, func : LibGee::FutureFlatMapFunc, func_target : Void*, func_target_destroy_notify : LibGLib::DestroyNotify) : LibGee::Future*
 >  906 |   fun future_get_value = gee_future_get_value(this : Future*) : Void*
 >  907 |   fun future_get_ready = gee_future_get_ready(this : Future*) : Bool
 >  908 |   fun future_get_exception = gee_future_get_exception(this : Future*) : LibGLib::Error**

Possibly the relevant file within Gee:

https://github.com/GNOME/libgee/blob/5e66324654b7d70d7c28793491a4edfe6d8a0d85/gee/future.vala#L132

[jhass]

So there's no info about FutureMapFunc in the GIR:

$ bin/gi-dump -n4 Gee
+ Future (interface)
...
  * methods
...
      + map (function)
...
        * args
...
            + func (arg)
              * direction = ZERO_NONE
              * optional = false
              * nullable = false
              * type
                  + <no name> (type)
                    * tag = INTERFACE
                    * pointer = false
                    * interface
                      + FutureMapFunc (unresolved)
...

From the source we can see it's a MapFunc, which we have info about in the GIR, but we could only hardcode that relationship into the generator which is... uh. I wonder how other generators solve this?

For now I updated the generator to use Void* for unresolved type references, so it should at least compile now and probably even work when you pass a MapFunc and type cast it to Void*. Well and handle all the closure data fun.

[aljelly]

It's building now, thanks. I'll leave this issue open as the case should probably be correctly handled as you said.