Allow bypassing the json spec by serializing infinite floats

Author: Evgeny Tankhilevich

.gitignore

@@ -1,4 +1,5 @@
 .DS_Store
+Manifest.toml
 docs/build/
 docs/site/
 *.jl.cov

Project.toml

@@ -4,7 +4,6 @@ authors = ["Jacob Quinn <[email protected]>"]
 version = "1.0.1"
 
 [deps]
-Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 Parsers = "69de0a69-1ddd-5017-9359-2bf0b02dc9f0"
 StructTypes = "856f2bd8-1eba-4b0a-8007-ebc267875bd4"
 Mmap = "a63ad114-7e13-5084-954f-fe012c677804"
@@ -21,4 +20,3 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
 test = ["Test"]
-

src/write.jl

@@ -171,8 +171,8 @@ function write(::NumberType, buf, pos, len, y::Integer; kw...)
 end
 
 write(::NumberType, buf, pos, len, x::T; kw...) where {T} = write(NumberType(), buf, pos, len, StructTypes.numbertype(T)(x); kw...)
-function write(::NumberType, buf, pos, len, x::AbstractFloat; kw...)
-    isfinite(x) || error("$x not allowed to be written in JSON spec")
+function write(::NumberType, buf, pos, len, x::AbstractFloat; allow_inf::Bool=false, kw...)
+    isfinite(x) || allow_inf || error("$x not allowed to be written in JSON spec")
     bytes = codeunits(Base.string(x))
     sz = sizeof(bytes)
     @check sz
@@ -183,8 +183,8 @@ function write(::NumberType, buf, pos, len, x::AbstractFloat; kw...)
     return buf, pos, len
 end
 
-@inline function write(::NumberType, buf, pos, len, x::T; kw...) where {T <: Base.IEEEFloat}
-    isfinite(x) || error("$x not allowed to be written in JSON spec")
+@inline function write(::NumberType, buf, pos, len, x::T; allow_inf::Bool=false, kw...) where {T <: Base.IEEEFloat}
+    isfinite(x) || allow_inf || error("$x not allowed to be written in JSON spec")
     @check Parsers.neededdigits(T)
     pos = Parsers.writeshortest(buf, pos, x)
     return buf, pos, len

test/json.jl

@@ -32,6 +32,10 @@ end
 @testset "Floats" begin
     @test_throws ErrorException JSON3.write([NaN])
     @test_throws ErrorException JSON3.write([Inf])
+    @test JSON3.write([NaN], allow_inf=true) == "[NaN]"
+    @test JSON3.write([Inf], allow_inf=true) == "[Inf]"
+    @test JSON3.read("[Inf]", Vector{Float64}) == [Inf]
+    @test JSON3.read("[nan]", Vector{Float64}) == [NaN]
 end
 
 @testset "Char" begin