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41 lines
1.0 KiB
Go
41 lines
1.0 KiB
Go
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// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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package bzip_test
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import (
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"bytes"
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"compress/bzip2" // reader
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"io"
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"testing"
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"gopl.io/ch13/bzip" // writer
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)
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func TestBzip2(t *testing.T) {
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var compressed, uncompressed bytes.Buffer
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w := bzip.NewWriter(&compressed)
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// Write a repetitive message in a million pieces,
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// compressing one copy but not the other.
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tee := io.MultiWriter(w, &uncompressed)
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for i := 0; i < 1000000; i++ {
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io.WriteString(tee, "hello")
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}
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if err := w.Close(); err != nil {
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t.Fatal(err)
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}
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// Check the size of the compressed stream.
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if got, want := compressed.Len(), 255; got != want {
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t.Errorf("1 million hellos compressed to %d bytes, want %d", got, want)
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}
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// Decompress and compare with original.
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var decompressed bytes.Buffer
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io.Copy(&decompressed, bzip2.NewReader(&compressed))
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if !bytes.Equal(uncompressed.Bytes(), decompressed.Bytes()) {
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t.Error("decompression yielded a different message")
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}
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}
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