In working with Vanilla Perl on Win32, I keep finding modules that fail their tests due to hardcoded slashes in their test scripts. Even modules that are pretty good about using File::Spec in the module itself seem to slip up during testing. For example:

use Test::More tests => 1;

use My::Module qw/get_a_filename/;  # gives a path with backslashes

my $expected = "some/file/path/here";

is( get_a_filename(), $expected );

[download]

I considered writing Test::FilePath that would run arguments through File::Spec->canonpath() automatically:

use Test::FilePath tests => 1;

filepath_is( "some/path", "some\path" );

[download]

That works for Win32, since canonpath() changes forward-slashes to back-slashes, but I don't think it works for other OSes like MacOS (Classic) that use things like ":" for separators.

Getting a truly platform-independent filepath comparison to a hard-coded test expectation seems like it would require one of these approaches:

  1. Hardcode the path components separately and assemble them at runtime using File::Spec.

    my @expected = qw{ some file path here };
is( get_a_filename(), File::Spec->join( @expected ) );

    [download]

  2. Use a convention that expected filepaths are always in Unix-style, and use a test helper to split and remap to the local directory separator convention.

    my $expected = "some/file/path/here";
filepath_is( "some:file:path:here", $expected );

    [download]

Do you prefer one over the other? How have you approached this problem? Are there other ideas you'd suggest? What edge cases do you anticipate? Would you use something like Test::FilePath (despite the extra dependency)?

Your input is greatly appreciated.

P.S. And if you do have hardcoded slashes in some module test on CPAN, please go fix that!

-xdg

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In reply to Portable filename comparison for test files by xdg

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