2-argument deserialize should be internal

[eschnett]

When implementing serialization for a type I defined, I accidentally called deserialize with two arguments, passing the expected type as second argument. Since the respective field was declared as AbstractString, this is the type I passed. As a result, I received a very strange error message:

ERROR: you must implement endof(AbstractString)

It seems as if deserialize created an object of type AbstractString that (of course) later cannot be handled.

This reproduces the error:

io=IOBuffer()
serialize(io, "hello")
s=SerializationState(IOBuffer(io.data))
deserialize(s, AbstractString)

[JeffBezanson]

Yes, in hindsight it's clear to me that the 2-argument deserialize should be private (i.e. renamed).

[mbauman]

Well we no longer create abstract types... we just segfault:

julia> using Serialization

julia> s = Serializer(IOBuffer())
Serializer{IOBuffer}(IOBuffer(data=UInt8[...], readable=true, writable=true, seekable=true, append=false, size=0, maxsize=Inf, ptr=1, mark=-1), 0, IdDict{Any, Any}(), Int64[], ^[[BDict{UInt64, Any}(), 15)

julia> serialize(s, "hello")

julia> seekstart(s.io)
IOBuffer(data=UInt8[...], readable=true, writable=true, seekable=true, append=false, size=7, maxsize=Inf, ptr=1, mark=-1)

julia> v = deserialize(s, AbstractString);

signal (11): Segmentation fault: 11
in expression starting at none:0
jl_field_offset at /Users/mbauman/Julia/master/src/./julia.h:1098 [inlined]
set_nth_field at /Users/mbauman/Julia/master/src/datatype.c:1099
jl_f_tuple at /Users/mbauman/Julia/master/src/builtins.c:787
indexed_iterate at ./pair.jl:50 [inlined]
indexed_iterate at ./pair.jl:50
jfptr_indexed_iterate_31423 at /Users/mbauman/Julia/master/usr/lib/julia/sys.dylib (unknown line)
jl_apply_generic at /Users/mbauman/Julia/master/src/gf.c:0

[LilithHafner]

This throws a reasonable error in 1.9.0

julia> using Serialization

julia> s = Serializer(IOBuffer())
Serializer{IOBuffer}(IOBuffer(data=UInt8[...], readable=true, writable=true, seekable=true, append=false, size=0, maxsize=Inf, ptr=1, mark=-1), 0, IdDict{Any, Any}(), Int64[], Dict{UInt64, Any}(), 20)

julia> serialize(s, "hello")

julia> seekstart(s.io)
IOBuffer(data=UInt8[...], readable=true, writable=true, seekable=true, append=false, size=7, maxsize=Inf, ptr=1, mark=-1)

julia> v = deserialize(s, AbstractString);
ERROR: TypeError: in new, expected DataType, got Type{AbstractString}
Stacktrace:
 [1] deserialize(s::Serializer{IOBuffer}, t::DataType)
   @ Serialization ~/.julia/juliaup/julia-1.9.0+0.aarch64.apple.darwin14/share/julia/stdlib/v1.9/Serialization/src/Serialization.jl:1492
 [2] top-level scope
   @ REPL[5]:1

[KristofferC]

#14090 (comment) seems like it stands.