37 lines
518 B
Go
37 lines
518 B
Go
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package textfmt_test
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import (
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"errors"
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"io"
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)
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type failingWriter struct {
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out io.Writer
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failAfter int
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err error
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}
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func (w *failingWriter) Write(p []byte) (int, error) {
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if w.err != nil {
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return 0, w.err
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}
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if w.failAfter <= len(p) {
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p = p[:w.failAfter]
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}
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if len(p) > 0 && w.out != nil {
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if n, err := w.out.Write(p); err != nil {
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w.err = err
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return n, w.err
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}
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}
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w.failAfter -= len(p)
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if w.failAfter == 0 {
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w.err = errors.New("test write error")
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}
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return len(p), w.err
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}
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