From e7b831494ed2dfb7333f0cf59f91cd7f14f9f9b6 Mon Sep 17 00:00:00 2001
From: Mischa POSLAWSKY <perl@shiar.org>
Date: Sat, 14 Nov 2009 20:53:44 +0100
Subject: [PATCH] +++: tests

---
 t/10-ranges.t | 88 +++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 64 insertions(+), 24 deletions(-)

diff --git a/t/10-ranges.t b/t/10-ranges.t
index d96ebb5..84f4dbb 100644
--- a/t/10-ranges.t
+++ b/t/10-ranges.t
@@ -33,33 +33,40 @@ subtest 'uniform alphanumeric' => sub {
 };
 
 subtest 'context' => sub {
-	plan tests => 4;
-	my $index = List::Index->new([qw(
-		baa1 baa2  baa3 baaa  bbc cbc  daaa ea  eaaa zed
-	)]) or return;
-	is_deeply($index->ranges({pagesize => 2, context => 0}), [
-		qw(-baa. baa.-bbb bbc-daa. daaa-eaa. eaaa-)
-	], 'no context');
-	is_deeply($index->ranges({pagesize => 2}), [
-		qw(-a b c d e-)
-	], 'default context');  # context should be 1
-	is_deeply($index->ranges({pagesize => 2, context => 2}), [
-		qw(-a b-c d e-)
-	], 'overlap');  # first item equals second due to large context
-	is_deeply($index->ranges({pagesize => 2, context => 0, length => 1}), [
-		qw(-a b-c d e-)
-	], 'single char');
-
-	#pp($index->ranges({pagesize => 2, context => 2, length => 1}));
-};
-
-subtest 'distribution' => sub {
-	plan tests => 3;
+	plan tests => 9;
 	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
+		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...'
@@ -78,7 +85,40 @@ subtest 'distribution' => sub {
 		# 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 $index = List::Index->new([qw(
+		baa1 baa2  baa3 baaa  bbc cbc  daaa ea  eaaa zed
+	)]) or return;
+	is_deeply($index->ranges({pagesize => 2, context => 0}), [
+		qw(-baa. baa.-bbb bbc-daa. daaa-eaa. eaaa-)
+	], 'no context');
+	is_deeply($index->ranges({pagesize => 2}), [
+		qw(-a b c d e-)
+	], 'default context');  # context should be 1
+	is_deeply($index->ranges({pagesize => 2, context => 2}), [
+		qw(-a b-c d e-)
+	], 'overlap');  # first item equals second due to large context
+	is_deeply($index->ranges({pagesize => 2, context => 0, length => 1}), [
+		qw(-a b-c d e-)
+	], 'single char');
+
+	#pp($index->ranges({pagesize => 2, context => 2, length => 1}));
+};
 
-- 
2.30.0