[perl #126993] [BUG] Test failure in t/spec/S19-command-line/dash-e.t

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# New Ticket Created by  A. Sinan Unur 
# Please include the string:  [perl #126993]
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When running the test with the original file which has:

is_run $x, :args['-e', "print q[\c[LATIN SMALL LETTER A WITH DOT ABOVE]]"],
{
     out => "\c[LATIN SMALL LETTER A WITH DOT ABOVE]",
     err => '',
     status => 0,
}, '-e print $something works with non-ASCII string literals';

I get:

# Failed test '-e print $something works with non-ASCII string literals'
# at D:\Src\rakudo\t\spec\packages\Test\Util.pm line 58
#      got out: "?"
# expected out: "ȧ"

If I change the test to

is_run $x,  :args['-e', "print q[å]"],
    {
        out     => "å",

I get:

ok 2 - -e print $something works with non-ASCII string literals

However, if I replace it with the intended character:

is_run $x,  :args['-e', "print q[ȧ]"],
    {
        out     => "ȧ",

I again get:

# Failed test '-e print $something works with non-ASCII string literals'
# at D:\Src\rakudo\t\spec\packages\Test\Util.pm line 58
#      got out: "?"
# expected out: "ȧ"

The test file is encoded as UTF-8, the codepage is set to 65001 in my
command prompt window.

I don't understand why å works but ȧ fails, except that the former is
in "Latin-1 Supplement" and the latter is in "Latin Extended-B".

Also, for reference:

# Failed test '-e print $something works with non-ASCII string literals'
# at D:\Src\rakudo\t\spec\packages\Test\Util.pm line 58
#      got out: "i"
# expected out: "ı"

# Failed test '-e print $something works with non-ASCII string literals'
# at D:\Src\rakudo\t\spec\packages\Test\Util.pm line 58
#      got out: "g"
# expected out: "ğ"

Now, Windows command prompt is probably not where I would expect this
to work, except that maybe it can work, so I am reporting it as a
possible bug.

Here's my environment and build info:

C:\> ver
Microsoft Windows [Version 10.0.10586]

C:\> cl
Microsoft (R) C/C++ Optimizing Compiler Version 18.00.31101 for x64

C:\> nmake /?
Microsoft (R) Program Maintenance Utility Version 12.00.21005.1

C:\> D:\Src\rakudo\perl6 -V
...
perl6::language_version=6.b
perl6::codename=
perl6::release-number=
perl6::build-date=2015-12-22T15:06:37Z
perl6::version=2015.11-718-g73d193b
perl6::implementation=Rakudo