package.p6

#use Grammar::Debugger;

### Package : rakudo-star-ver-arch-build-tag.ext

 

grammar Pkg {
	token TOP		{ <ws> <name> <ver>? <arch>? <build>? <tag>? <ext>? }
	regex name	{ <alnum>+ [ '-' <alnum>+ ]* <!before '.'> } # using regex as name may contain "-"
	token ver		{ '-' <(<digit>+ ['.' <digit>+]+)> }  
	proto token arch { * }  # look-around asssertions for "arch" token doesn't work, Why!
	token arch:sym<x86_64>	{ '-' <(<sym>)> }
	token arch:sym<i386>		{ '-' <(<sym>)> }
	#token build	{ <?after <arch>> '-' <(<digit>+)> } # does not work, but <?after 'x86_64'> works
	token build	{ '-' <(<digit>+)> }
	token tag		{ '-' <(<alnum>+)> } # "tag" is optional in the package name.
	#token ext		{ <?after  [<build> | <tag>] > '.' <('pkg')> } # "ext" should come after ("build" or "tag") only
	token ext		{ '.' <('pkg')> }
}

 ### Issues ###
 #  grammar should fail to parse if a token matched in wrong location (for example: if arch token come before version token)
 #  rakudo-star-ver-arch.ext should fail, (ext only comes after build or tag tokens), however, grammar successfully parse it
 #  if I addede look-around assertions grammar doesn't match at all or other tests fail.

my @tests = (
# [ 'string to test', matches?, message ]
 [ 'rakudo-star',												True,		'name' ],
 [ 'rakudo-star-0.7',										True,		'name-ver' ],
 [ 'rakudo-star-0.7-x86_64',						True,		'name-ver-arch' ],
 [ 'rakudo-star-0.7-x86_64-0',					True,		'name-ver-arch-build' ],
 [ 'rakudo-star-0.7-x86_64-0.pkg',      True,		'name-ver-arch-build-ext' ],
 [ 'rakudo-star-0.7-x86_64-0-tag',      True,		'name-ver-arch-build-tag' ],
 [ 'rakudo-star-0.7-x86_64-0-tag.pkg',	True,		'name-ver-arch-build-tag.ext' ],
 [ 'rakudo-star-0.7-0',									False,	'build must come after arch' ],
 [ 'rakudo-star-0.7.pkg',								False,	'ext must come after build or tag' ],
);

for @tests -> [$string, $should-parse, $message] {
    my $m = Pkg.parse($string);
    my $result = ?$m;   # make boolean
    $result = !$result if $should-parse === False;
    say "[$result]\tt$string $message";

}