1 files changed, 43 insertions, 0 deletions
diff --git a/t/substrings.t b/t/substrings.t
new file mode 100644
index 0000000..c4f478b
--- /dev/null
+++ b/t/substrings.t
@@ -0,0 +1,43 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+use Test::More;
+
+use Games::Word qw(is_substring all_substrings);
+
+my %is_substring_tests = (
+    ""      => [""],
+    "abc",  => ["", "abc", "ab", "ac"],
+    "aaba"  => ["a", "aa", "aaa", "aab", "aba"],
+    "abcba" => ["aa", "bb", "c", "abc", "cba", "abba"],
+);
+my %isnt_substring_tests = (
+    ""      => ["a"],
+    "abc"   => ["z", "ba", "baz", "abz"],
+    "aaba"  => ["c", "abaa"],
+);
+my %all_substrings_tests = (
+    ""    => [''],
+    "a"   => ['', "a"],
+    "ab"  => ['', "a", "b", "ab"],
+    "aab" => ['', "a", "a", "b", "aa", "ab", "ab", "aab"],
+    "abc" => ['', "a", "b", "c", "ab", "ac", "bc", "abc"],
+);
+
+for my $word (keys %is_substring_tests) {
+    ok(is_substring($_, $word), "is '$_' a substring of '$word'?")
+        for @{ $is_substring_tests{$word} };
+}
+for my $word (keys %isnt_substring_tests) {
+    ok(!is_substring($_, $word), "is '$_' not a substring of '$word'?")
+        for @{ $isnt_substring_tests{$word} };
+}
+for my $word (keys %all_substrings_tests) {
+    is_deeply(
+        [sort(all_substrings($word))],
+        [sort(@{ $all_substrings_tests{$word} })],
+        "do we get all of the substrings of '$word'?"
+    );
+}
+
+done_testing;