add seek operations to NoopStream (#26)

Author: bicycle1885

src/noop.jl

@@ -41,6 +41,24 @@ function TranscodingStream(codec::Noop, stream::IO;
     return TranscodingStream(codec, stream, State(buffer, buffer))
 end
 
+function Base.seek(stream::NoopStream, pos::Integer)
+    seek(stream.stream, pos)
+    initbuffer!(stream.state.buffer1)
+    return
+end
+
+function Base.seekstart(stream::NoopStream)
+    seekstart(stream.stream)
+    initbuffer!(stream.state.buffer1)
+    return
+end
+
+function Base.seekend(stream::NoopStream)
+    seekend(stream.stream)
+    initbuffer!(stream.state.buffer1)
+    return
+end
+
 function Base.unsafe_read(stream::NoopStream, output::Ptr{UInt8}, nbytes::UInt)
     changemode!(stream, :read)
     buffer = stream.state.buffer1

test/runtests.jl

@@ -95,6 +95,17 @@ end
     @test !ismarked(stream)
     close(stream)
 
+    stream = TranscodingStream(Noop(), IOBuffer(b"foobarbaz"))
+    seek(stream, 2)
+    @test read(stream, 3) == b"oba"
+    seek(stream, 0)
+    @test read(stream, 3) == b"foo"
+    seekstart(stream)
+    @test read(stream, 3) == b"foo"
+    seekend(stream)
+    @test eof(stream)
+    close(stream)
+
     data = collect(0x00:0x0f)
     stream = TranscodingStream(Noop(), IOBuffer(data))
     @test read(stream, UInt8) == data[1]