}
		}

		// Read the data with occasional UnreadByte calls.
		for i := 0; i < n; i++ {
			readTo('d', "abcd")
			for j := 0; j < 3; j++ {
				if err := r.UnreadByte(); err != nil {
					t.Fatalf("#%d: unexpected error on UnreadByte: %v", rno, err)
				}
				readTo('d', "d")
			}
			readTo('g', "efg")
		}

		// All data should have been read.
		_, err := r.ReadByte()
		if err != io.EOF {

				"application/vnd.bmi",
				"application/vnd.businessobjects",
				"application/vnd.cab-jscript",
				"application/vnd.canon-cpdl",
				"application/vnd.canon-lips",
				"application/vnd.cendio.thinlinc.clientconf",
				"application/vnd.chemdraw+xml",
				"application/vnd.chipnuts.karaoke-mmd",
				"application/vnd.cinderella",
				"application/vnd.cirpack.isdn-ext",
				"application/vnd.claymore",