Move to common tag expression evaluation

Cucumber::TagExpressions provides the infrastructure to use
a common tag selection 'language' across implementations. By
using it, we don't have to invent our own.

Author: ehuelsmann

bin/pherkin

@@ -53,11 +53,8 @@ Extra Steps
 
 Tag specifications
 
- -t, --tags @tag        Run scenarios tagged with '@tag'
- -t, --tags @tag1,@tag2 Run scenarios tagged with '@tag1' or '@tag2'
- -t, --tags ~@tag       Run scenarios tagged without '@tag'
- -t @tag1 -t @tag2      Run only scenarios tagged with '@tag1' and '@tag2'
- -t @tag1 -t ~@tag2     Run scenarios tagged with '@tag1' but not '@tag2'
+ -t, --tags <expr>      Run scenarios for which the tags satisfy the
+                        cucumber tag expression <expr>
 
 Configuration profiles (see CONFIGURATION PROFILES below/`man pherkin`)
 
@@ -112,12 +109,11 @@ command line. C<default> is used if you didn't specify one. For example:
      - foo/steps
      - ~/steps
    output: TermColor
-   tags:
-     - tag1,tag2
+   tags: @tag1 or @tag2
 
 is equivalent to:
 
-  --steps foo/steps --steps ~/steps --output TermColor --tags tag1,tag2
+  --steps foo/steps --steps ~/steps --output TermColor --tags '@tag1 or @tag2'
 
 If you specify both command-line options, and options in a configuration file,
 then the command-line ones override single-value items, and are placed at the

cpanfile

@@ -1,5 +1,6 @@
 
-requires 'perl', '5.010';
+requires 'perl', '5.014';
+requires 'Cucumber::TagExpressions', '5.0.5';
 requires 'File::Find::Rule';
 requires 'JSON::MaybeXS', '1.1.0';
 # List::Util 1.33 adds 'any'

lib/App/pherkin.pm

@@ -14,6 +14,8 @@ use Data::Dumper;
 use File::Spec;
 use Path::Class qw/file dir/;
 
+use Cucumber::TagExpressions;
+
 use Test::BDD::Cucumber::I18n
     qw(languages langdef readable_keywords keyword_to_subname);
 use Test::BDD::Cucumber::Loader;
@@ -22,8 +24,7 @@ use Moo;
 use Types::Standard qw( ArrayRef Bool Str );
 has 'step_paths' => ( is => 'rw', isa => ArrayRef, default => sub { [] } );
 has 'extensions' => ( is => 'rw', isa => ArrayRef, default => sub { [] } );
-has 'tags'       => ( is => 'rw', isa => ArrayRef, required => 0 );
-has 'tag_scheme' => ( is => 'rw', isa => ArrayRef, required => 0 );
+has 'tags'       => ( is => 'rw', isa => Str,      required => 0 );
 has 'match_only' => ( is => 'rw', isa => Bool,     default => 0 );
 has 'matching'   => ( is => 'rw', isa => Str,      default => 'first');
 has 'strict'     => ( is => 'rw', isa => Bool,     default => 0 );
@@ -114,9 +115,8 @@ sub _run_tests {
     $harness->startup();
 
     my $tag_spec;
-    if ( $self->tag_scheme ) {
-        $tag_spec = Test::BDD::Cucumber::Model::TagSpec->new(
-            { tags => $self->tag_scheme } );
+    if ( $self->tags ) {
+        $tag_spec = Cucumber::TagExpressions->parse( $self->tags );
     }
 
     $executor->execute( $_, $harness, $tag_spec ) for @features;
@@ -324,7 +324,7 @@ sub _process_arguments {
         output     => [ 'o|output=s' ],
         strict     => [ 'strict' ],
         steps      => [ 's|steps=s@', [] ],
-        tags       => [ 't|tags=s@', [] ],
+        tags       => [ 't|tags=s' ],
         i18n       => [ 'i18n=s' ],
         extensions => [ 'e|extension=s@', [] ],
         matching   => [ 'matching=s' ],
@@ -477,9 +477,6 @@ sub _process_arguments {
     # Store any extra step paths
     $self->step_paths( $deref->('steps') );
 
-    # Store our TagSpecScheme
-    $self->tag_scheme( $self->_process_tags( @{ $deref->('tags') } ) );
-
     $self->matching( $deref->('matching') )
         if $deref->('matching');
 
@@ -492,42 +489,6 @@ sub _process_arguments {
     return ( pop @ARGV );
 }
 
-sub _process_tags {
-    my ( $self, @tags ) = @_;
-
-    # This is a bit faffy and possibly suboptimal.
-    my $tag_scheme = [];
-    my @ands       = ();
-
-    # Iterate over our commandline tag strings.
-    foreach my $tag (@tags) {
-        my @parts = ();
-
-        foreach my $part ( split( ',', $tag ) ) {
-
-            # Trim any @ or ~@ from the front of the tag
-            $part =~ s/^(~?)@//;
-
-            # ~@tag => "NOT tag" => [ not => tag ]
-            if ( defined $1 and $1 eq '~' ) {
-                push @parts, [ not => $part ];
-            } else {
-                push @parts, $part;
-            }
-        }
-
-        # @tag,@cow => "@tag OR @cow" => [ or => tag, cow ]
-        # (It's simpler to always stick an 'or' on the front.)
-        push @ands, [ or => @parts ];
-    }
-
-    # -t @tag -t @cow => "@tag AND @cow" => [ and => tag, cow ]
-    # (It's simpler to always stick an 'and' on the front.)
-    $tag_scheme = [ and => @ands ];
-
-    return $tag_scheme;
-}
-
 sub _print_languages {
 
     my @languages = languages();

lib/Test/BDD/Cucumber/Executor.pm

@@ -1,3 +1,6 @@
+
+use v5.14;
+
 package Test::BDD::Cucumber::Executor;
 
 =head1 NAME
@@ -17,6 +20,7 @@ use Types::Standard qw( Bool Str ArrayRef HashRef );
 use List::Util qw/first any/;
 use Module::Runtime qw/use_module/;
 use utf8;
+use Carp qw(carp croak);
 use Encode ();
 
 use Test2::API qw/intercept/;
@@ -142,7 +146,7 @@ sub add_steps {
 =head2 execute
 
 Execute accepts a feature object, a harness object, and an optional
-L<Test::BDD::Cucumber::TagSpec> object and for each scenario in the
+L<Cucumber::TagExpressions::ExpressionNode> object and for each scenario in the
 feature which meets the tag requirements (or all of them, if you
 haven't specified one), runs C<execute_scenario>.
 
@@ -202,6 +206,23 @@ representing the Background
 
 =cut
 
+sub _match_tags {
+    my ($spec, @tagged_components) = @_;
+    state $deprecation_warned = 0;
+
+    if ($spec->isa('Cucumber::TagExpressions::ExpressionNode')) {
+        return grep {
+            $spec->evaluate( @{ $_->tags } )
+        } @tagged_components;
+    }
+    else {
+        $deprecation_warned ||=
+            carp 'Test::BDD::Cucumber::Model::TagSpec is deprecated; replace with Cucumber::TagExpressions';
+
+        return $spec->filter( @tagged_components );
+    }
+}
+
 sub execute_outline {
     my ( $self, $options ) = @_;
     my ( $feature, $feature_stash, $harness, $outline, $background, $tagspec )
@@ -210,7 +231,7 @@ sub execute_outline {
     # Multiply out Scenario Outlines as appropriate
     my @datasets = @{ $outline->datasets };
     if (not @datasets) {
-        if (not $tagspec or $tagspec->filter($outline) ) {
+        if (not $tagspec or _match_tags( $tagspec, $outline )) {
             $self->execute_scenario(
                 {
                     feature => $feature,
@@ -227,7 +248,7 @@ sub execute_outline {
     }
 
     if ($tagspec) {
-        @datasets = $tagspec->filter(@datasets);
+        @datasets = _match_tags( $tagspec, @datasets );
         return unless @datasets;
     }
 

lib/Test/BDD/Cucumber/Model/TagSpec.pm

@@ -4,6 +4,12 @@ package Test::BDD::Cucumber::Model::TagSpec;
 
 Test::BDD::Cucumber::Model::TagSpec - Encapsulates tag selectors
 
+=head1 STATUS
+
+DEPRECATED - This module's functionality has been superseeded by
+L<Cucumber::TagExpressions>. A module published by the Cucumber
+project, with cross-implementation tests to achieve overall consistency.
+
 =head1 DESCRIPTION
 
 Try and deal with the crazy-sauce tagging mechanism in a sane