Merge pull request #34 from lwabeke/betterSupportForNothing

Better support for nothing

Project.toml

@@ -1,7 +1,7 @@
 name = "Unmarshal"
 uuid = "cbff2730-442d-58d7-89d1-8e530c41eb02"
 authors = ["Leon Wabeke <[email protected]>", "Sunoru <[email protected]>"]
-version = "0.4.1"
+version = "0.4.2"
 
 [deps]
 JSON = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"

src/Unmarshal.jl

@@ -112,16 +112,18 @@ function unmarshal(DT :: Type, parsedJson :: AbstractDict, verbose :: Bool = fal
            prettyPrint(verboseLvl-1, "\\--> $(iter) <: $(DTNext) ")
         end
 
-        if !haskey(parsedJson, string(iter)) 
+        if !haskey(parsedJson, string(iter)) || isnothing(parsedJson[string(iter)])
             # check whether DTNext is compatible with any scheme for missing values
             val = if DTNext <: Nullable
                 DTNext()
             elseif Missing <: DTNext
                 missing
             elseif Nothing <: DTNext
                 Nothing()
-            else
+            elseif !haskey(parsedJson, string(iter))
                 throw(ArgumentError("Key $(string(iter)) is missing from the structure $DT, and field is neither Nullable nor Missings nor Nothing-compatible"))
+            else 
+                throw(ArgumentError("Key $(string(iter)) is null, but the field is neither Nullable nor Missings nor Nothing-compatible"))
             end
         else
             val = unmarshal( DTNext, parsedJson[string(iter)], verbose, verboseLvl)
@@ -229,9 +231,15 @@ unmarshal(::Type{T}, x::Number, verbose :: Bool = false, verboseLvl :: Int = 0)
 unmarshal(::Type{Nullable{T}}, x, verbose :: Bool = false, verboseLvl :: Int = 0) where T = Nullable(unmarshal(T, x))
 unmarshal(::Type{Nullable{T}}, x::Nothing, verbose :: Bool = false, verboseLvl :: Int = 0) where T = Nullable{T}()
 unmarshal(::Type{Union{T,Missing}}, x, verbose :: Bool = false, verboseLvl :: Int = 0) where T = unmarshal(T, x, verbose, verboseLvl)
-unmarshal(::Type{Union{T,Nothing}}, x, verbose :: Bool = false, verboseLvl :: Int = 0) where T = unmarshal(T, x, verbose, verboseLvl)
+unmarshal(::Type{Union{T,Nothing}}, x::Nothing, verbose :: Bool = false, verboseLvl :: Int = 0) where T = nothing
+unmarshal(::Type{Union{T,Nothing}}, x::T, verbose :: Bool = false, verboseLvl :: Int = 0) where T = unmarshal(T, x, verbose, verboseLvl)
 
-unmarshal(T::Type, x, verbose :: Bool = false, verboseLvl :: Int = 0) =
-    throw(ArgumentError("no unmarshal function defined to convert $(typeof(x)) to $(T); consider providing a specialization"))
+function unmarshal(T::Type, x, verbose :: Bool = false, verboseLvl :: Int = 0) 
+    try
+        T(x)
+    catch
+        throw(ArgumentError("no unmarshal function defined to convert $(typeof(x)) to $(T); consider providing a specialization"))
+    end
+end
 
 end # module

src/lazyjson.jl

@@ -58,3 +58,9 @@ function unmarshal(DT :: Type{Pair{TF, TS}}, parsedJson :: LazyJSON.Object, verb
 
     (firstVal => secondVal)
 end
+
+unmarshal(::Type{T}, x::Number, verbose :: Bool = false, verboseLvl :: Int = 0) where T <: Number = T(x)
+unmarshal(::Type{Union{T,Nothing}}, x::LazyJSON.Number, verbose :: Bool = false, verboseLvl :: Int = 0) where T <: Number = T(x)
+unmarshal(::Type{Nullable{T}}, x::LazyJSON.Number, verbose :: Bool = false, verboseLvl :: Int = 0) where T <: Number = Nullable(T(x))
+unmarshal(::Type{Union{T,Missing}}, x::LazyJSON.Number, verbose :: Bool = false, verboseLvl :: Int = 0) where T <: Number= T(x)
+

test/unmarshal.jl

@@ -282,3 +282,39 @@ p = ( 24 => Dict("hours"=>24, "min"=>60) )
 q = ( 24 => "Test" )
 @test Unmarshal.unmarshal(typeof(p), JSON.parse(JSON.json(p)), true) == p
 @test_throws ArgumentError Unmarshal.unmarshal(typeof(p), JSON.parse(JSON.json(q)), true) 
+
+struct User
+    id::Union{Int64, Nothing}
+    id_str::Union{String, Nothing}
+    created_at::Union{String, Nothing}
+    name::Union{String, Nothing}
+    screen_name::Union{String, Nothing}
+    location::Union{String, Nothing}
+    statuses_count::Union{Int64, Nothing}
+    followers_count::Union{Int64, Nothing}
+    description::Union{String, Nothing}
+    profile_image_url::Union{String, Nothing}
+end
+
+struct Tweet
+    id::Union{Int64, Nothing}
+    id_str::Union{String, Nothing}
+    created_at::Union{String, Nothing}
+    favorite_count::Union{Int, Nothing}
+    retweet_count::Union{Int, Nothing}
+    full_text::Union{String, Nothing}
+    lang::Union{String, Nothing}
+    place::Union{String, Nothing}
+    truncated::Union{Bool, Nothing}
+    user::User
+end
+
+json_str = "{\"id_str\":\"1305501948074835974\",\"created_at\":\"Mon Sep 14 13:41:34 +0000 2020\",\"place\":null,\"id\":1305501948074835974,\"user\":{\"name\":\"Donald J. Trump\",\"id_str\":\"25073877\",\"created_at\":\"Wed Mar 18 13:46:38 +0000 2009\",\"id\":25073877}}"
+@test isa(Unmarshal.unmarshal(Tweet, JSON.parse(json_str), true),Tweet)
+
+mutable struct TestStruct
+    test::Symbol
+end
+packedDict = Dict{String,Any}("test" => "testValue")
+@test isa(Unmarshal.unmarshal(TestStruct, packedDict), TestStruct)
+