Merge pull request #58 from baumgold/custom_string_repr

#57 enable custom string representation of missing and nothing values

Author: pfitzseb

src/TableView.jl

@@ -263,9 +263,9 @@ function table2json(schema, rows, types; requested = nothing)
                 if val isa Number && isfinite(val)
                     JSON.print(io, val)
                 elseif val === nothing
-                    JSON.print(io, "nothing")
+                    JSON.print(io, repr(nothing))
                 elseif val === missing
-                    JSON.print(io, "missing")
+                    JSON.print(io, repr(missing))
                 else
                     JSON.print(io, sprint(print, val))
                 end

test/runtests.jl

@@ -19,16 +19,18 @@ end
     ]
     @test showtable(nttable) isa WebIO.Scope
 end
-@testset "inf and nan serializing" begin
-    rows = Tables.table([NaN Inf -Inf 0])
-    names = [:a, :b, :c, :d]
-    types = [Float64 for _ in 1:4]
+@testset "inf, nan, and missing serializing" begin
+    rows = Tables.table([NaN Inf -Inf 0 missing])
+    names = [:a, :b, :c, :d, :e]
+    types = vcat([Float64 for _ in 1:4], [Missing])
+    Base.show(io::IO, x::Missing) = print(io, "test_missing")
     json = TableView.table2json(Tables.Schema(names, types), rows, types)
     firstrow = JSON.parse(json)[1]
     @test firstrow["a"] == "NaN"
     @test firstrow["b"] == "Inf"
     @test firstrow["c"] == "-Inf"
     @test firstrow["d"] == 0
+    @test firstrow["e"] == "test_missing"
 end
 @testset "normal array" begin
     array = rand(10, 10)