https://issues.dlang.org/show_bug.cgi?id=17241

          Issue ID: 17241
           Summary: std.file.rename exceptions should include both 'from'
                    and 'to' file paths
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: minor
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: acehreli@yahoo.com

Currently, the exception message makes sense only if the problem is with the 'to' file path.

1) BAD CASE:

import std.file;

void main() {
    rename("some_non_existing_file.txt", "bar.txt");
}

Unfortunately, the exception includes the target file name:

std.file.FileException@std/file.d(681): bar.txt: No such file or directory
[...]

DISCUSSION: The fix seems to be trivial by replacing the last argument with fromz below:

phobos/std/file.d:681:
        cenforce(core.stdc.stdio.rename(fromz, toz) == 0, t, toz);

However, it's not that simple because in some cases it's toz that needs to be reported.

2) GOOD CASE:

import std.file;

void main() {
    // Assuming that foo.txt exists:
    rename("foo.txt", "some/non/existing/path/bar.txt");
}

std.file.FileException@std/file.d(681): some/non/existing/path/bar.txt: No such
file or directory
[...]

So, it makes sense to include both paths.

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