Use a concrete type rather than abstract (Julia 1.0 issue).

Author: MichaelHatherly

test/TestModule/M.jl

@@ -16,7 +16,7 @@ h_3(x::A{T}) where {T} = x
 h_4(x, ::Int, z) = x
 
 @generated g_1(x) = x
-@generated g_2(x::Integer) = x
+@generated g_2(x::String) = x
 
 i_1(x; y = x) = x * y
 i_2(x::Int; y = x) = x * y

test/tests.jl

@@ -209,13 +209,13 @@ end
 
             doc.data = Dict(
                 :binding => Docs.Binding(M, :g_2),
-                :typesig => Tuple{Integer},
+                :typesig => Tuple{String},
                 :module => M,
             )
             DSE.format(TYPEDSIGNATURES, buf, doc)
             str = String(take!(buf))
             @test occursin("\n```julia\n", str)
-            @test occursin("\ng_2(x::Integer)", str)
+            @test occursin("\ng_2(x::String)", str)
             @test occursin("\n```\n", str)
 
             doc.data = Dict(