[Issue 15293] File().byLine().map!toUpper throws UnicodeException at src\rt\util\utf.d(290): invalid UTF-8 sequence on pure ASCII file

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15293

--- Comment #4 from HeiHon <heiko.honrath at web.de> ---
The shortest reductions I could find are with:

    std.file.write("gen.txt", "12\n\n1x\n");
or
    std.file.write("gen.txt", "1\n\n1x");

So it does not depend on the lacking \n at the end.

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