Widen signature of read!(::IO, ::Array) to AbstractArray (#33046)

Co-Authored-By: Matt Bauman <mbauman@gmail.com>
JuliaLang · Dec 10, 2019 · 1dbccbd · 1dbccbd
1 parent 46b7bb2
commit 1dbccbd
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Showing 2 changed files with 26 additions and 4 deletions.
diff --git a/base/io.jl b/base/io.jl
@@ -381,8 +381,8 @@ read(filename::AbstractString, args...) = open(io->read(io, args...), filename)
 read(filename::AbstractString, ::Type{T}) where {T} = open(io->read(io, T), filename)
 
 """
-    read!(stream::IO, array::Union{Array, BitArray})
-    read!(filename::AbstractString, array::Union{Array, BitArray})
+    read!(stream::IO, array::AbstractArray)
+    read!(filename::AbstractString, array::AbstractArray)
 
 Read binary data from an I/O stream or file, filling in `array`.
 """
@@ -682,8 +682,8 @@ function read!(s::IO, a::Array{UInt8})
     return a
 end
 
-function read!(s::IO, a::Array{T}) where T
-    if isbitstype(T)
+function read!(s::IO, a::AbstractArray{T}) where T
+    if isbitstype(T) && (a isa Array || a isa FastContiguousSubArray{T,<:Any,<:Array{T}})
         GC.@preserve a unsafe_read(s, pointer(a), sizeof(a))
     else
         for i in eachindex(a)

diff --git a/test/read.jl b/test/read.jl
@@ -574,3 +574,25 @@ end
 
 # issue #26419
 @test Base.return_types(read, (String, Type{String})) == Any[String]
+
+@testset "read! to view" begin
+    x = rand(4, 4)
+    y = rand(10)
+    z = 1:10
+    v = [1.0, 2.0, 3.0, 4.0]
+    io = IOBuffer()
+    write(io, v)
+    flush(io)
+    seekstart(io)
+    read!(io, @view x[:, 3])
+    @test x[:, 3] == v
+    x = rand(3, 3)
+    seekstart(io)
+    read!(io, @view x[1:2, 2:3])
+    @test x[1:2, 2:3][:] == v[:]
+    seekstart(io)
+    read!(io, @view y[4:7])
+    @test y[4:7] == v
+    seekstart(io)
+    @test_throws ErrorException read!(io, @view z[4:6])
+end