XXX: distribution test

[perl/list-index.git] / t / 10-ranges.t

diff --git a/t/10-ranges.t b/t/10-ranges.t
index ef292b1f55ab67a4b110d19ffde6462093d0bc98..cf3b0a43addfdcd94ccff68764967358e783f7ce 100644 (file)
--- a/t/10-ranges.t
+++ b/t/10-ranges.t
@@ -2,7 +2,7 @@
 use strict;
 use warnings;
 
-use Test::More tests => 6;
+use Test::More tests => 8;
 use Test::NoWarnings;
 use Data::Dump 'pp';
 
@@ -32,6 +32,101 @@ subtest 'uniform alphanumeric' => sub {
        is_deeply($index->ranges({pagesize => 300}), [qw(-c d-n o-)], 'large pagesize');
 };
 
+subtest 'context' => sub {
+       plan tests => 9;
+       my $index = List::Index->new([qw(
+               kkeg kl km kmlu knsy    koxb kpeo kuaa kuab kuac
+               kuapa kuq kur kux kzb   lc lg lgu lgua lguc
+               lguq lgur lgus lgx lka  lkq lks lln llq llx
+       )]) or return;
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>0, length=>5 }),
+               # ranges should match offsets exactly
+               [qw(-kuap. kuapa-lgup lguq-)],
+               'no context'
+       );
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>0 }),
+               # default length limits to 4 chars
+               [qw(-kuao kuap-lgup lguq-)],
+               'default length'
+       );
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>1 }),
+               # lookbehinds aren't shorter (kuac<kuap, lguc<lguq)
+               # 'kuap' can advance to 'kuq'
+               [qw(-kup kuq-lgup lguq-)],
+               'lookahead'
+       );
+TODO: {
+       local $TODO = 'backtrack';
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>2 }),
+               # allowed to advance to 'kur', but provides no benefits over 'kuq'
+               [qw(-kup kuq-lgup lguq-)],
+               'minimal lookahead'
+       );
+}
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>3 }),
+               # shorten 'kuap' to 'ku' because lookbehind is 'kp...'
+               # 'lguq' matches 'lg', but may only backtrack to 'lgu'
+               [qw(-kt ku-lgt lgu-)],
+               'lookbehind'
+       );
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>4 }),
+               [qw(-kt ku-lf lg-)],
+               'maximal lookahead'
+       );
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>5 }),
+               # after forwarding 'kuap' to 'lc'
+               # disallow backtracking of 'lguq' to 'lc' to prevent qw[-k l-]
+               # so only lookahead (to 'lkq') remains
+               [qw(-k l-lj lk-)],
+               'lookbehind forbidden'
+       );
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>9 }),
+               # allow a single (10-9) entry (l-lf = lc) to remain
+               [qw(-k l-lf lg-)],
+               'lookbehind penalty'
+       );
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>10 }),
+               # allow the last page to go back upto 'lc', replacing the 2nd page
+               [qw(-k l-)],
+               'full overlap'
+       );
+};
+
+subtest 'distribution' => sub {
+       plan tests => 2;
+       my $index = List::Index->new([qw(
+               gnihka gniub go gsearnrqns gtdvcxyt gw gwoufolwcvmtueyg gysgphci h habkdgifjfxoh
+               hbbvjf hbqleexnqts hccg hd hdoeqwdmgqwaoya hfbegicieuxz hfm hj hkoysmws hmylu
+               hnvtvpievbdlkrmb hs hvdvcqn hvn hyrybeur iaiaab ib ibavqyar idfniqvxpohbk idh
+       )]) or return;
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>6 }),
+               [qw(-g h i-)],
+               'large context'
+       );
+{ local $TODO = '?';
+       is_deeply(
+               $index->ranges({ pagesize=>10, context=>5 }),
+               # after 2nd page is enlarged by lookbehind to 'h', limit subsequent lookahead
+               # to prevent the page from getting too large (17 entries if forwarded to 'i')
+               [qw(-g h-hm hn-)],
+               'lookahead penalty'
+       );
+       # page #14 [gn-g] (8): gnihka gniub go gsearnrqns gtdvcxyt gwawkvmueovdjtfj gwoufolwcvmtueyg gysgphci
+       # page #15 [h] (17): h habkdgifjfxoh hbbvjf hbqleexnqts hccgszftbaymfu hdaqzkow hdoeqwdmgqwaoya hfbegicieu hfmlpzzioqjbthz hj hkoysmws hmylu hnvtvpievbdlkrmb hsodfpkatk hvdvcqn hvn hyrybeurqtevjfmi
+       # page #16 [i-ie] (5): i iaab ibiavqyar idfniqvxpohbk idh
+}
+};
+
 subtest 'context' => sub {
        plan tests => 4;
        my $index = List::Index->new([qw(