diff --git a/NEWS.md b/NEWS.md
index 7aa726480..f43335f76 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -4,11 +4,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [0.13.1] - Unreleased
+## [0.13.1] - 2020-7-24
 
 ### Fixed
 
-  - Bug associated with `LinCom` kernel and triangulations with 0 cells. Since PR [#331](/~https://github.com/gridap/Gridap.jl/pull/331/).
+  - Bugs associated with the degenerated case of 0-length arrays. Since PR [#331](/~https://github.com/gridap/Gridap.jl/pull/331/) and [#332](/~https://github.com/gridap/Gridap.jl/pull/332/).
 
 ## [0.13.0] - 2020-07-23
 
diff --git a/src/Arrays/Apply.jl b/src/Arrays/Apply.jl
index 5bc9d1fbe..ae801ca2a 100644
--- a/src/Arrays/Apply.jl
+++ b/src/Arrays/Apply.jl
@@ -226,9 +226,7 @@ function testitem(a::AppliedArray)
   cg = array_cache(a.g)
   gi = testitem(a.g)
   fi = testitems(a.f...)
-  cf = array_caches(a.f...)
-  ai = kernel_testitem(gi,fi...)
-  ai
+  kernel_testitem(gi,fi...)
 end
 
 function getindex!(cache,a::AppliedArray,i::Integer...)
diff --git a/src/Arrays/CompressedArrays.jl b/src/Arrays/CompressedArrays.jl
index 846dc6443..81691b1b3 100644
--- a/src/Arrays/CompressedArrays.jl
+++ b/src/Arrays/CompressedArrays.jl
@@ -30,7 +30,11 @@ struct CompressedArray{T,N,A,P} <: AbstractArray{T,N}
 end
 
 function testitem(a::CompressedArray)
-  testitem(a.values)
+  if length(a.ptrs) == 0
+    testitem(a.values)
+  else
+    a.values[first(a.ptrs)]
+  end
 end
 
 size(a::CompressedArray) = size(a.ptrs)
diff --git a/src/Arrays/Interface.jl b/src/Arrays/Interface.jl
index 4be55eb72..e324cc577 100644
--- a/src/Arrays/Interface.jl
+++ b/src/Arrays/Interface.jl
@@ -193,6 +193,10 @@ function test_array(
   end
   @test t
   @test IndexStyle(a) == IndexStyle(b)
+  @test isa(testitem(a),eltype(a))
+  if length(a) > 0
+    @test testitem(a) == first(a)
+  end
   true
 end
 
diff --git a/src/Arrays/Kernels.jl b/src/Arrays/Kernels.jl
index 5ed8f4f4c..0fba25073 100644
--- a/src/Arrays/Kernels.jl
+++ b/src/Arrays/Kernels.jl
@@ -30,10 +30,10 @@ abstract type Kernel <: GridapType end
 Returns the type of the result of calling kernel `f` with
 arguments of the types of the objects `x`.
 
-It defaults to `typeof(apply_kernel(f,x...))`
+It defaults to `typeof(kernel_testitem(f,x...))`
 """
 function kernel_return_type(f,x...)
-  typeof(apply_kernel(f,x...))
+  typeof(kernel_testitem(f,x...))
 end
 
 """
diff --git a/src/Arrays/LocalToGlobalArrays.jl b/src/Arrays/LocalToGlobalArrays.jl
index ff952df6c..a82e078e8 100644
--- a/src/Arrays/LocalToGlobalArrays.jl
+++ b/src/Arrays/LocalToGlobalArrays.jl
@@ -21,12 +21,6 @@ struct LocalToGlobalArray{T,M,N,L,V} <: AbstractArray{Array{T,M},N}
   end
 end
 
-function testitem(a::LocalToGlobalArray)
-  val = testitem(a.gid_to_val)
-  gids = testitem(a.lid_to_gid)
-  fill(val,size(gids))
-end
-
 size(a::LocalToGlobalArray) = size(a.lid_to_gid)
 
 function IndexStyle(::Type{LocalToGlobalArray{T,M,N,L,V}}) where {T,M,N,L,V}
diff --git a/src/Arrays/LocalToGlobalPosNegArrays.jl b/src/Arrays/LocalToGlobalPosNegArrays.jl
index d4cd1e970..c0bc1be98 100644
--- a/src/Arrays/LocalToGlobalPosNegArrays.jl
+++ b/src/Arrays/LocalToGlobalPosNegArrays.jl
@@ -23,12 +23,6 @@ struct LocalToGlobalPosNegArray{T,M,N,L,V,W} <: AbstractArray{Array{T,M},N}
   end
 end
 
-function testitem(a::LocalToGlobalPosNegArray)
-  val = testitem(a.gid_to_val_pos)
-  gids = testitem(a.lid_to_gid)
-  fill(val,size(gids))
-end
-
 size(a::LocalToGlobalPosNegArray) = size(a.lid_to_gid)
 
 function IndexStyle(::Type{<:LocalToGlobalPosNegArray{T,M,N,L}}) where {T,M,N,L}
diff --git a/src/Arrays/Reindex.jl b/src/Arrays/Reindex.jl
index b7757faca..8048643d3 100644
--- a/src/Arrays/Reindex.jl
+++ b/src/Arrays/Reindex.jl
@@ -48,8 +48,6 @@ end
   a.i_to_v[i]=v
 end
 
-
-
 function testitem(a::Reindexed)
   if length(a.j_to_i) == 0
     testitem(a.i_to_v)
diff --git a/test/ArraysTests/ApplyTests.jl b/test/ArraysTests/ApplyTests.jl
index 6a80384d5..b7b25d7dd 100644
--- a/test/ArraysTests/ApplyTests.jl
+++ b/test/ArraysTests/ApplyTests.jl
@@ -128,6 +128,53 @@ r = map(+,a,b)
 test_array(c,r)
 @test isa(c,Fill)
 
+l = 10
+ai = [8 0; 0 4]
+a = Fill(ai,l)
+c = apply(inv,a)
+r = map(inv,a)
+test_array(c,r)
+@test isa(c,Fill)
+
+l = 10
+ai = [8 0; 0 4]
+a = fill(ai,l)
+c = apply(inv,a)
+r = map(inv,a)
+test_array(c,r)
+
+l = 0
+ai = [8 0; 0 4]
+a = fill(ai,l)
+c = apply(inv,a)
+r = map(inv,a)
+test_array(c,r)
+
+ai = [8 0; 0 4]
+a = CompressedArray([ai,],Int[])
+c = apply(inv,a)
+r = map(inv,a)
+test_array(c,r)
+
+l = 10
+ai = [8, 0]
+a = fill(ai,l)
+f(ai) = ai[2]-ai[1]
+c = apply(f,a)
+r = map(f,a)
+test_array(c,r)
+
+g(ai) = ai[2]-ai[1]
+import Gridap.Arrays: kernel_testitem!
+kernel_testitem!(c,::typeof(g),ai) = zero(eltype(ai))
+l = 0
+ai = [8, 0]
+a = fill(ai,l)
+c = apply(g,a)
+r = map(g,a)
+test_array(c,r)
+
+
 #f = rand(10)
 #a = rand(10)
 #@test apply(f,a) === f
diff --git a/test/ArraysTests/LocalToGlobalArraysTests.jl b/test/ArraysTests/LocalToGlobalArraysTests.jl
index 467f41911..8580a0a2d 100644
--- a/test/ArraysTests/LocalToGlobalArraysTests.jl
+++ b/test/ArraysTests/LocalToGlobalArraysTests.jl
@@ -18,13 +18,11 @@ r = reindex(ca,ids)
 @test isa(r,LocalToGlobalArray)
 test_array(r,ca[ids])
 
-
 i_to_v=[[1, 2], [5, 6], [1, 5], [2, 6], [2, 3], [6, 7], [3, 7], [3, 4], [7, 8], [4, 8], [9, 10], [5, 9], [6, 10], [10, 11], [7, 11], [11, 12], [8, 12], [13, 14], [9, 13], [10, 14], [14, 15], [11, 15], [15, 16], [12, 16]]
 j_to_i=Int64[]
 lid_to_gid=reindex(i_to_v,j_to_i)
 gid_to_val=VectorValue{2,Float64}[(0.0, 0.25), (0.25, 0.25), (0.5, 0.25), (0.75, 0.25), (0.0, 0.5), (0.25, 0.5), (0.5, 0.5), (0.75, 0.5), (0.0, 0.75), (0.25, 0.75), (0.5, 0.75), (0.75, 0.75), (0.0, 1.0), (0.25, 1.0), (0.5, 1.0), (0.75, 1.0)]
 f2=LocalToGlobalArray(lid_to_gid,gid_to_val)
-@test 2 == length(testitem(f2))
-
+test_array(f2,Vector{VectorValue{2,Float64}}[])
 
 end # module
diff --git a/test/ArraysTests/LocalToGlobalPosNegArraysTests.jl b/test/ArraysTests/LocalToGlobalPosNegArraysTests.jl
index 61dcc360b..c31f715e8 100644
--- a/test/ArraysTests/LocalToGlobalPosNegArraysTests.jl
+++ b/test/ArraysTests/LocalToGlobalPosNegArraysTests.jl
@@ -19,6 +19,6 @@ j_to_i=Int64[]
 lid_to_gid=reindex(i_to_v,j_to_i)
 gid_to_val=VectorValue{2,Float64}[(0.0, 0.25), (0.25, 0.25), (0.5, 0.25), (0.75, 0.25), (0.0, 0.5), (0.25, 0.5), (0.5, 0.5), (0.75, 0.5), (0.0, 0.75), (0.25, 0.75), (0.5, 0.75), (0.75, 0.75), (0.0, 1.0), (0.25, 1.0), (0.5, 1.0), (0.75, 1.0)]
 f2=LocalToGlobalPosNegArray(lid_to_gid,gid_to_val,gid_to_val)
-@test 2 == length(testitem(f2))
+test_array(f2,Vector{VectorValue{2,Float64}}[])
 
 end # module
diff --git a/test/FESpacesTests/ExtendedFESpacesTests.jl b/test/FESpacesTests/ExtendedFESpacesTests.jl
index 1cbb968e0..0f2f90e20 100644
--- a/test/FESpacesTests/ExtendedFESpacesTests.jl
+++ b/test/FESpacesTests/ExtendedFESpacesTests.jl
@@ -52,6 +52,14 @@ incell_to_cell = findall(oldcell_to_is_in)
 outcell_to_cell = findall(collect(Bool, .! oldcell_to_is_in))
 
 model_in = DiscreteModel(model,incell_to_cell)
+
+V = TestFESpace(
+  model=model_in,valuetype=Float64,reffe=:Lagrangian,
+  order=1,conformity=:H1,dof_space=:physical)
+@test isa(V,ExtendedFESpace)
+
+
+
 model_out = DiscreteModel(model,outcell_to_cell)
 
 trian_in = RestrictedTriangulation(trian, incell_to_cell)