Merge pull request JuliaLang#22941 from JuliaLang/jb/fix6466

fix JuliaLang#6466, deprecate `write` on non-isbits arrays

NEWS.md

@@ -234,6 +234,9 @@ Deprecated or removed
  * The function `showall` is deprecated. Showing entire values is the default, unless an
  `IOContext` specifying `:limit=>true` is in use ([#22847]).
 
+ * Calling `write` on non-isbits arrays is deprecated in favor of explicit loops or
+ `serialize` ([#6466]).
+
 
 Julia v0.6.0 Release Notes
 ==========================

base/deprecated.jl

@@ -1596,6 +1596,9 @@ end
 
 @deprecate momenttype(::Type{T}) where {T} typeof((zero(T)*zero(T) + zero(T)*zero(T))/2) false
 
+# issue #6466
+# `write` on non-isbits arrays is deprecated in io.jl.
+
 # END 0.7 deprecations
 
 # BEGIN 1.0 deprecations

base/io.jl

@@ -314,21 +314,21 @@ write(s::IO, x::Bool) = write(s, UInt8(x))
 write(to::IO, p::Ptr) = write(to, convert(UInt, p))
 
 function write(s::IO, A::AbstractArray)
+ if !isbits(eltype(A))
+ depwarn("Calling `write` on non-isbits arrays is deprecated. Use a loop or `serialize` instead.", :write)
+ end
  nb = 0
  for a in A
  nb += write(s, a)
  end
  return nb
 end
 
-@noinline function write(s::IO, a::Array{UInt8}) # mark noinline to ensure the array is gc-rooted somewhere (by the caller)
- return unsafe_write(s, pointer(a), sizeof(a))
-end
-
-@noinline function write(s::IO, a::Array{T}) where T # mark noinline to ensure the array is gc-rooted somewhere (by the caller)
- if isbits(T)
+@noinline function write(s::IO, a::Array) # mark noinline to ensure the array is gc-rooted somewhere (by the caller)
+ if isbits(eltype(a))
  return unsafe_write(s, pointer(a), sizeof(a))
  else
+ depwarn("Calling `write` on non-isbits arrays is deprecated. Use a loop or `serialize` instead.", :write)
  nb = 0
  for b in a
  nb += write(s, b)
@@ -337,6 +337,27 @@ end
  end
 end
 
+function write(s::IO, a::SubArray{T,N,<:Array}) where {T,N}
+ if !isbits(T)
+ return invoke(write, Tuple{IO, AbstractArray}, s, a)
+ end
+ elsz = sizeof(T)
+ colsz = size(a,1) * elsz
+ if stride(a,1) != 1
+ for idxs in CartesianRange(size(a))
+ unsafe_write(s, pointer(a, idxs.I), elsz)
+ end
+ return elsz * length(a)
+ elseif N <= 1
+ return unsafe_write(s, pointer(a, 1), colsz)
+ else
+ for idxs in CartesianRange((1, size(a)[2:end]...))
+ unsafe_write(s, pointer(a, idxs.I), colsz)
+ end
+ return colsz * trailingsize(a,2)
+ end
+end
+
 
 function write(s::IO, ch::Char)
  c = reinterpret(UInt32, ch)

base/iostream.jl

@@ -169,21 +169,6 @@ function unsafe_write(s::IOStream, p::Ptr{UInt8}, nb::UInt)
  return Int(ccall(:ios_write, Csize_t, (Ptr{Void}, Ptr{Void}, Csize_t), s.ios, p, nb))
 end
 
-function write(s::IOStream, a::SubArray{T,N,<:Array}) where {T,N}
- if !isbits(T) || stride(a,1)!=1
- return invoke(write, Tuple{Any, AbstractArray}, s, a)
- end
- colsz = size(a,1)*sizeof(T)
- if N<=1
- return unsafe_write(s, pointer(a, 1), colsz)
- else
- for idxs in CartesianRange((1, size(a)[2:end]...))
- unsafe_write(s, pointer(a, idxs.I), colsz)
- end
- return colsz*trailingsize(a,2)
- end
-end
-
 # num bytes available without blocking
 nb_available(s::IOStream) = ccall(:jl_nb_available, Int32, (Ptr{Void},), s.ios)
 

test/strings/basic.jl

@@ -79,11 +79,13 @@ end
 @test_throws ArgumentError gensym("ab\0")
 
 # issue #6949
-let f =IOBuffer(),
+let f = IOBuffer(),
  x = split("1 2 3")
- @test write(f, x) == 3
- @test String(take!(f)) == "123"
- @test invoke(write, Tuple{IO, AbstractArray}, f, x) == 3
+ local nb = 0
+ for c in x
+ nb += write(f, c)
+ end
+ @test nb == 3
  @test String(take!(f)) == "123"
 end