From 0cffa6161e871bb33477ce94e1c6e794eb5e15b5 Mon Sep 17 00:00:00 2001
From: Rob Emery <mintsoft@users.noreply.github.com>
Date: Tue, 7 Mar 2017 04:39:09 +0000
Subject: [PATCH] POTUS: Triggering is way too keen (#3938)

* POTUS: Adding failing test for overtrigger

* POTUS: the previous || $prez_count meant that it defaulted to the current president if it didn't recognise the number; hence why it was showing so many false positives

* POTUS: Now with stricter handling on the $num we can trust the validation later on to keep us safe from overtriggering

* POTUS: basic queries that really should work!

* POTUS: Switching to using a guard regex to match things rather than using replacements

* POTUS: Guard regex now protects the query space. and "was" is used to imply the previous president (currently obama)

* POTUS: switched to query_lc and implementing both a guard regex and a replacement for the triggers so that the code below behaves as if it is remainder =>, except that this doesn't erroneously replace "president-elect of the us" with ""

* POTUS: We don't need $rem
---
 lib/DDG/Goodie/POTUS.pm | 26 ++++++++++++++++----------
 t/POTUS.t               |  5 +++++
 2 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/lib/DDG/Goodie/POTUS.pm b/lib/DDG/Goodie/POTUS.pm
index b7e8cf89e..b101a428e 100755
--- a/lib/DDG/Goodie/POTUS.pm
+++ b/lib/DDG/Goodie/POTUS.pm
@@ -16,18 +16,24 @@ zci is_cached   => 1;
 
 my @presidents = @{LoadFile(share('presidents.yml'))};
 my $prez_count = scalar @presidents;
+my $potus_or_president = qr/(potus|president of the (us|united states))/i;
 
-handle remainder => sub {
-    my $rem = shift;
-    return if $rem =~ /vice/i;
-    $rem =~ s/
-      |who\s+(is|was)\s+the\s+
-      |^POTUS\s+
-      |\s+(POTUS|president\s+of\s+the\s+united\s+states)$
-      |^(POTUS|president\s+of\s+the\s+united\s+states)\s+
-    //gix;
+handle query_lc => sub {
+
+    # workaround for president-elect of the united states being classed as a trigger
+    s/(^$potus_or_president\s)|(\s$potus_or_president\s?[\?]?$)//i;
+
+    /^
+      (who\s+(?<iswas>is|was)\s*(?:the\s*)?(?<num>.*))
+      |(?<num>.*)
+    $/gix or return;
+
+    my $num;
+    $num = $prez_count if $+{num} eq "";
+    $num = $prez_count -1 if $+{num} eq "" and $+{iswas} eq "was";
+    $num = words2nums($+{num}) if words2nums($+{num});
+    return unless $num;
 
-    my $num = ($rem =~ /^\d+$/) ? $rem : words2nums($rem) || $prez_count;
     my $index = $num - 1;
     return if $index < 0 or $index > $#presidents;
 
diff --git a/t/POTUS.t b/t/POTUS.t
index 55b889473..aa35c83a4 100755
--- a/t/POTUS.t
+++ b/t/POTUS.t
@@ -26,6 +26,8 @@ sub build_test
 
 ddg_goodie_test(
     [qw( DDG::Goodie::POTUS)],
+    'who is the president of the united states' => build_test('Donald J. Trump', 'is',"45th"),
+    'who was the president of the united states' => build_test('Barack Obama', 'was', '44th'),
     'who is president of the united states' => build_test('Donald J. Trump', 'is',"45th"),
     'who is the fourth president of the united states' => build_test('James Madison', 'was', '4th'),
     'who is the nineteenth president of the united states' => build_test('Rutherford B. Hayes', 'was','19th'),
@@ -38,6 +40,9 @@ ddg_goodie_test(
     'potus 16' => build_test('Abraham Lincoln', 'was', '16th'),
     'who is the vice president of the united states?' => undef,
     'vice president of the united states' => undef,
+    'who is the worst president of the united states' => undef,
+    'who is the president elect of the united states' => undef,
+    'who is the president-elect of the us' => undef,
     'VPOTUS' => undef
 );