[phobos] [D-Programming-Language/phobos] 994d6b: fix issue 15293

[GitHub via phobos]

  Branch: refs/heads/stable
  Home:   https://github.com/D-Programming-Language/phobos
  Commit: 994d6b81815bc70ab8507ece7285b49ef5ce6d2d
      https://github.com/D-Programming-Language/phobos/commit/994d6b81815bc70ab8507ece7285b49ef5ce6d2d
  Author: anonymous <aG0aep6G at users.noreply.github.com>
  Date:   2015-11-12 (Thu, 12 Nov 2015)

  Changed paths:
    M std/stdio.d

  Log Message:
  -----------
  fix issue 15293

ReadlnAppender tried to claim the capacity of the passed buffer, calling
assumeSafeAppend on the result so that on the next call it has a capacity
again that can be claimed.

The obvious problem with that: readln would stomp over memory that it has
not been given.

There was also a subtler problem with it (which caused issue 15293):
When readln wasn't called with the previous line, but with the original
buffer (byLine does that), then the passed buffer had no capacity, so
ReadlnAppender would not assumeSafeAppend when slicing the new line from
it. But without a new assumeSafeAppend, the last one would still be in
effect, possibly on a sub slice of the new line.


  Commit: 15b550da7275558936569099a7396d06300b3576
      https://github.com/D-Programming-Language/phobos/commit/15b550da7275558936569099a7396d06300b3576
  Author: anonymous <aG0aep6G at users.noreply.github.com>
  Date:   2015-11-13 (Fri, 13 Nov 2015)

  Changed paths:
    M std/stdio.d

  Log Message:
  -----------
  avoid .capacity


  Commit: fc77dbbfa93d126c5dfec7c03cc8939b819c09a9
      https://github.com/D-Programming-Language/phobos/commit/fc77dbbfa93d126c5dfec7c03cc8939b819c09a9
  Author: Steven Schveighoffer <schveiguy at yahoo.com>
  Date:   2015-11-13 (Fri, 13 Nov 2015)

  Changed paths:
    M std/stdio.d

  Log Message:
  -----------
  Merge pull request #3802 from aG0aep6G/15293

fix issue 15293


Compare: https://github.com/D-Programming-Language/phobos/compare/57ba76a95604...fc77dbbfa93d