fix show for non-array (#564)

Author: CarloLucibello

.gitignore

@@ -19,3 +19,4 @@ GraphNeuralNetworks/docs/src/GNNGraphs
 GraphNeuralNetworks/docs/src/GNNlib
 tutorials/docs/build
 prova.jl
+pyg.ipynb

GNNGraphs/src/gnngraph.jl

@@ -230,16 +230,20 @@ function Base.copy(g::GNNGraph; deep = false)
     end
 end
 
+feature_summary(x::AbstractArray) = "$(dims2string(size(x)))"
+feature_summary(x::AbstractString) = "string($(length(x)))"
+feature_summary(x::T) where T = "$T"
+
 function print_feature(io::IO, feature)
     if !isempty(feature)
         if length(keys(feature)) == 1
             k = first(keys(feature))
             v = first(values(feature))
-            print(io, "$(k): $(dims2string(size(v)))")
+            print(io, "$(k): $(feature_summary(v))")
         else
             print(io, "(")
             for (i, (k, v)) in enumerate(pairs(feature))
-                print(io, "$k: $(dims2string(size(v)))")
+                print(io, "$k: $(feature_summary(v))")
                 if i == length(feature)
                     print(io, ")")
                 else

GNNGraphs/test/gnngraph.jl

@@ -344,6 +344,13 @@ end
     @test g1 !== g2
 end
 
+@testset "show" begin
+    # no throw when global data is not an array
+    g = rand_graph(10, 20, gdata = "ciao")
+    @test sprint(show, g) == "GNNGraph(10, 20) with u: string(4) data"
+    @test sprint(show, MIME("text/plain"), g) == "GNNGraph:\n  num_nodes: 10\n  num_edges: 20\n  gdata:\n    u = 4-codeunit String"
+end
+
 ## Cannot test this because DataStore is not an ordered collection
 ## Uncomment when/if it will be based on OrderedDict
 # @testset "show" begin