Error with quadrilateral mesh generated from Gmsh + Lowest-order Nedelec FEs

The error is reproduced with MWE below (mesh file attached).

Please see my explanation below on the cause of the problem.

Versions of packages:

* GridapGmsh v0.6.0
* Gridap v0.17.13 `https://github.com/gridap/Gridap.jl#master` (46b538895f4d035374d0e76091b6888870fadac9)

[refined_lshape.zip](https://github.com/gridap/Gridap.jl/files/9100571/refined_lshape.zip)

```julia
using Gridap
using GridapGmsh
mesh_file="refined_lshape.msh"
order = 0
reffe = ReferenceFE(nedelec, Float64, order)
model = GmshDiscreteModel(mesh_file)
writevtk(model,"m")
V0 = FESpace(model, reffe; dirichlet_tags=["dirichlet_surfaces", "dirichlet_points"])
```

And the error is:

```
ERROR: BoundsError: attempt to access 1-element Vector{Vector{Int64}} at index [2]
Stacktrace:
[1] getindex
@ ./array.jl:861 [inlined]
[2] getindex
@ ./abstractarray.jl:1221 [inlined]
[3] getindex!(cache::Gridap.Arrays.CachedVector{Int32, Vector{Int32}}, a::Gridap.FESpaces.CellDofsNonOriented, cell::Int64)
@ Gridap.FESpaces ~/.julia/packages/Gridap/JCqMt/src/FESpaces/ConformingFESpaces.jl:555
[4] _generate_data_and_ptrs_fill_ptrs!(ptrs::Vector{Int32}, vv::Gridap.FESpaces.CellDofsNonOriented)
@ Gridap.Arrays ~/.julia/packages/Gridap/JCqMt/src/Arrays/Tables.jl:151
[5] generate_data_and_ptrs(vv::Gridap.FESpaces.CellDofsNonOriented)
@ Gridap.Arrays ~/.julia/packages/Gridap/JCqMt/src/Arrays/Tables.jl:139
[6] Table
@ ~/.julia/packages/Gridap/JCqMt/src/Arrays/Tables.jl:27 [inlined]
[7] compute_conforming_cell_dofs(cell_fe::Gridap.FESpaces.CellFE{Vector{Int8}}, cell_conformity::Gridap.FESpaces.CellConformity{Vector{Int8}}, grid_topology::Gridap.Geometry.UnstructuredGridTopology{2, 2, Float64, Gridap.Geometry.NonOriented}, face_labeling::Gridap.Geometry.FaceLabeling, dirichlet_tags::Vector{String}, dirichlet_components::Nothing)
@ Gridap.FESpaces ~/.julia/packages/Gridap/JCqMt/src/FESpaces/ConformingFESpaces.jl:269
[8] _ConformingFESpace(vector_type::Type, model::Gridap.Geometry.UnstructuredDiscreteModel{2, 2, Float64, Gridap.Geometry.NonOriented}, face_labeling::Gridap.Geometry.FaceLabeling, cell_fe::Gridap.FESpaces.CellFE{Vector{Int8}}, dirichlet_tags::Vector{String}, dirichlet_components::Nothing, trian::Gridap.Geometry.BodyFittedTriangulation{2, 2, Gridap.Geometry.UnstructuredDiscreteModel{2, 2, Float64, Gridap.Geometry.NonOriented}, Gridap.Geometry.UnstructuredGrid{2, 2, Float64, Gridap.Geometry.NonOriented, Nothing}, Gridap.Arrays.IdentityVector{Int64}})
@ Gridap.FESpaces ~/.julia/packages/Gridap/JCqMt/src/FESpaces/ConformingFESpaces.jl:148
[9] FESpace(model::Gridap.Geometry.UnstructuredDiscreteModel{2, 2, Float64, Gridap.Geometry.NonOriented}, cell_fe::Gridap.FESpaces.CellFE{Vector{Int8}}; trian::Gridap.Geometry.BodyFittedTriangulation{2, 2, Gridap.Geometry.UnstructuredDiscreteModel{2, 2, Float64, Gridap.Geometry.NonOriented}, Gridap.Geometry.UnstructuredGrid{2, 2, Float64, Gridap.Geometry.NonOriented, Nothing}, Gridap.Arrays.IdentityVector{Int64}}, labels::Gridap.Geometry.FaceLabeling, dirichlet_tags::Vector{String}, dirichlet_masks::Nothing, constraint::Nothing, vector_type::Type)
@ Gridap.FESpaces ~/.julia/packages/Gridap/JCqMt/src/FESpaces/FESpaceFactories.jl:23
[10] FESpace(model::Gridap.Geometry.UnstructuredDiscreteModel{2, 2, Float64, Gridap.Geometry.NonOriented}, cell_reffe::Gridap.Arrays.CompressedArray{Gridap.ReferenceFEs.GenericRefFE{Nedelec, 2}, 1, Vector{Gridap.ReferenceFEs.GenericRefFE{Nedelec, 2}}, Vector{Int8}}; conformity::Nothing, trian::Gridap.Geometry.BodyFittedTriangulation{2, 2, Gridap.Geometry.UnstructuredDiscreteModel{2, 2, Float64, Gridap.Geometry.NonOriented}, Gridap.Geometry.UnstructuredGrid{2, 2, Float64, Gridap.Geometry.NonOriented, Nothing}, Gridap.Arrays.IdentityVector{Int64}}, labels::Gridap.Geometry.FaceLabeling, dirichlet_tags::Vector{String}, dirichlet_masks::Nothing, constraint::Nothing, vector_type::Nothing)
@ Gridap.FESpaces ~/.julia/packages/Gridap/JCqMt/src/FESpaces/FESpaceFactories.jl:111
[11] FESpace(model::Gridap.Geometry.UnstructuredDiscreteModel{2, 2, Float64, Gridap.Geometry.NonOriented}, reffe::Tuple{Nedelec, Tuple{DataType, Int64}, Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}}}; kwargs::Base.Pairs{Symbol, Vector{String}, Tuple{Symbol}, NamedTuple{(:dirichlet_tags,), Tuple{Vector{String}}}})
@ Gridap.FESpaces ~/.julia/packages/Gridap/JCqMt/src/FESpaces/FESpaceFactories.jl:126
[12] top-level scope
@ ~/git-repos/Gridap.jl/mwe.jl:10
```

# Explanation

As far as I understand GridapGmsh is returning a quadrilateral mesh which is non-oriented

And the current implementation of Nedelec FEs on quadrilaterals does not seem to support non-oriented quadrilateral meshes

Let me explain how I have arrived to that conclusion.

If you execute Table(get_cell_permutations(grid_topology)) with grid_topology being the grid_topology object related to the model

you will get a cell-wise array of arrays, where the array associated to each cell is of size 9 (1..4 vertices, 5..8 edges, 9 cell interior)

the relevant portion of these arrays is the one corresponding to the edges, i.e., positions 5..8 of these arrays

the two possible orientations of an edge within a cell are coded with 1 and 2 resp.

if there is at least one edge for which the orientations of the edge from the perspective of both cells around do not match, i.e., if 1 versus 2 or 2 versus 1, then the mesh is a non-oriented mesh

If you look at the array returned by Table(get_cell_permutations(grid_topology)) you will see 2s and 1s there, so that I guess that the mesh is non-oriented

the indices in the array returned by Table(get_cell_permutations(grid_topology)) are used to indirectly address another array within the CellConformity object, which is called ctype_lface_pindex_pdofs

the third nested index from left to right is the one which is feed from Table(get_cell_permutations(grid_topology))

ctype_lface_pindex_pdofs[ctype][lface][pindex]

the cause of the problem is that the length of ctype_lface_pindex_pdofs[ctype][lface] is 1

so that when we use the 2s in Table(get_cell_permutations(grid_topology)) to feed ctype_lface_pindex_pdofs[ctype][lface][pindex] we get an out-of-bounds error

Reproduce the MWE with GridapGmsh's GmshDiscreteModel and the Nedelec FESpace, then follow the failure through CellDofsNonOriented into ConformingFESpaces.jl. Check the quadrilateral cell permutations and CellConformity indexing; done means the non-oriented quadrilateral mesh no longer raises the reported BoundsError.

Written by the indexing model from the issue text.