+++: tests
[perl/list-index.git] / t / 10-ranges.t
index f935820eaf99904bb4007478b3b3c51be8eb568b..84f4dbbc7f64dca807831325c08d2a4f29b9aece 100644 (file)
@@ -32,6 +32,75 @@ 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-)],
+               'no lookbehind after full lookahead'
+       );
+       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 after full lookahead'
+       );
+       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 'context' => sub {
        plan tests => 4;
        my $index = List::Index->new([qw(
@@ -53,27 +122,3 @@ subtest 'context' => sub {
        #pp($index->ranges({pagesize => 2, context => 2, length => 1}));
 };
 
-subtest 'distribution' => sub {
-       plan tests => 2;
-       my $index = List::Index->new([qw(
-               kkeg kl km kmlu knsy    koxb kpeo kuaa kuab kuac
-               kuap kuaq kuq kux kzb   lc lg lgu lgua lguc
-               lguq lgur lgus lgx lka  lkq lks lln llq llx
-       )]) or return;
-TODO: {
-       local $TODO = 'under development';
-       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'
-       );
-}
-