make stream types a subtype of TranscodingStream (fix d7a7a80)

Author: bicycle1885

src/compression.jl

@@ -33,7 +33,7 @@ function GzipCompression(;level::Integer=Z_DEFAULT_COMPRESSION,
     return GzipCompression(ZStream(), level, windowbits+16)
 end
 
-const GzipCompressionStream{S} = TranscodingStream{GzipCompression,S}
+const GzipCompressionStream{S} = TranscodingStream{GzipCompression,S} where S<:IO
 
 """
     GzipCompressionStream(stream::IO; kwargs...)
@@ -74,7 +74,7 @@ function ZlibCompression(;level::Integer=Z_DEFAULT_COMPRESSION,
     return ZlibCompression(ZStream(), level, windowbits)
 end
 
-const ZlibCompressionStream{S} = TranscodingStream{ZlibCompression,S}
+const ZlibCompressionStream{S} = TranscodingStream{ZlibCompression,S} where S<:IO
 
 """
     ZlibCompressionStream(stream::IO)
@@ -115,7 +115,7 @@ function DeflateCompression(;level::Integer=Z_DEFAULT_COMPRESSION,
     return DeflateCompression(ZStream(), level, -Int(windowbits))
 end
 
-const DeflateCompressionStream{S} = TranscodingStream{DeflateCompression,S}
+const DeflateCompressionStream{S} = TranscodingStream{DeflateCompression,S} where S<:IO
 
 """
     DeflateCompressionStream(stream::IO; kwargs...)

src/decompression.jl

@@ -31,7 +31,7 @@ function GzipDecompression(;windowbits::Integer=Z_DEFAULT_WINDOWBITS, gziponly::
     return GzipDecompression(ZStream(), windowbits+(gziponly?16:32))
 end
 
-const GzipDecompressionStream{S} = TranscodingStream{GzipDecompression,S}
+const GzipDecompressionStream{S} = TranscodingStream{GzipDecompression,S} where S<:IO
 
 """
     GzipDecompressionStream(stream::IO; kwargs...)
@@ -67,7 +67,7 @@ function ZlibDecompression(;windowbits::Integer=Z_DEFAULT_WINDOWBITS)
     return ZlibDecompression(ZStream(), windowbits)
 end
 
-const ZlibDecompressionStream{S} = TranscodingStream{ZlibDecompression,S}
+const ZlibDecompressionStream{S} = TranscodingStream{ZlibDecompression,S} where S<:IO
 
 """
     ZlibDecompressionStream(stream::IO; kwargs...)
@@ -103,7 +103,7 @@ function DeflateDecompression(;windowbits::Integer=Z_DEFAULT_WINDOWBITS)
     return DeflateDecompression(ZStream(), -Int(windowbits))
 end
 
-const DeflateDecompressionStream{S} = TranscodingStream{DeflateDecompression,S}
+const DeflateDecompressionStream{S} = TranscodingStream{DeflateDecompression,S} where S<:IO
 
 """
     DeflateDecompressionStream(stream::IO; kwargs...)

test/runtests.jl

@@ -66,6 +66,9 @@ const testdir = dirname(@__FILE__)
         @test length(read(path)) > 0
     end
 
+    @test GzipCompressionStream <: TranscodingStream
+    @test GzipDecompressionStream <: TranscodingStream
+
     test_roundtrip_read(GzipCompressionStream, GzipDecompressionStream)
     test_roundtrip_write(GzipCompressionStream, GzipDecompressionStream)
     test_roundtrip_lines(GzipCompressionStream, GzipDecompressionStream)
@@ -124,6 +127,9 @@ end
         @test read(path) == zlib_data
     end
 
+    @test ZlibCompressionStream <: TranscodingStream
+    @test ZlibDecompressionStream <: TranscodingStream
+
     test_roundtrip_read(ZlibCompressionStream, ZlibDecompressionStream)
     test_roundtrip_write(ZlibCompressionStream, ZlibDecompressionStream)
     test_roundtrip_lines(ZlibCompressionStream, ZlibDecompressionStream)
@@ -140,6 +146,9 @@ end
     test_roundtrip_lines(DeflateCompressionStream, DeflateDecompressionStream)
     test_roundtrip_transcode(DeflateCompression, DeflateDecompression)
 
+    @test DeflateCompressionStream <: TranscodingStream
+    @test DeflateDecompressionStream <: TranscodingStream
+
     @test_throws ArgumentError DeflateCompression(level=10)
     @test_throws ArgumentError DeflateCompression(windowbits=16)
     @test_throws ArgumentError DeflateDecompression(windowbits=16)