Merge pull request #13 from sealink/no_match_within_alphanumeric

Does not match credit cards numbers that are part of longer pattern

CHANGELOG.md

@@ -3,6 +3,10 @@ All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 This changelog adheres to [Keep a CHANGELOG](http://keepachangelog.com/).
 
+## [Unreleased]
+### Changed
+- Does not match credit cards numbers that are part of alphanumerical strings
+
 ## [0.2.3] - 2016-12-22
 ### Fixed
 - Ensures that the url returned by the occurrence is filtered

lib/sensitive_data_filter/types/credit_card.rb

@@ -8,7 +8,7 @@ module CreditCard
       SEPRS      = SEPARATORS.source + '*'
       LENGTHS    = (11..19)
       CARD       = Regexp.new(
-        LENGTHS.map { |length| /(?=((?<!\d)(?:\d#{SEPRS}){#{length - 1}}\d(?!\d))?)/.source }.join
+        LENGTHS.map { |length| /(?=(\b(?:\d#{SEPRS}){#{length - 1}}\d\b)?)/.source }.join
       )
       FILTERED = '[FILTERED]'
 

spec/sensitive_data_filter/types/credit_card_spec.rb

@@ -66,11 +66,41 @@ def validations(cards)
       specify { expect(scan).to be_empty }
     end
 
+    context 'a value that contains valid credit card numbers preceded by numbers' do
+      let(:value) { '1234111111111111111' }
+      specify { expect(scan).to be_empty }
+    end
+
+    context 'a value that contains valid credit card numbers followed by numbers' do
+      let(:value) { '4111111111111111321' }
+      specify { expect(scan).to be_empty }
+    end
+
     context 'a value that contains a valid credit card number separated from other numbers' do
       let(:value) { '123 4111 1111 1111 1111 234' }
       specify { expect(scan).to eq ['4111 1111 1111 1111'] }
     end
 
+    context 'a value that contains valid credit card numbers between letters' do
+      let(:value) { 'abc4111111111111111dfg' }
+      specify { expect(scan).to be_empty }
+    end
+
+    context 'a value that contains valid credit card numbers preceded by letters' do
+      let(:value) { 'abc4111111111111111' }
+      specify { expect(scan).to be_empty }
+    end
+
+    context 'a value that contains valid credit card numbers followed by letters' do
+      let(:value) { '4111111111111111abc' }
+      specify { expect(scan).to be_empty }
+    end
+
+    context 'a value that contains a valid credit card number separated from other characters' do
+      let(:value) { 'abc 4111 1111 1111 1111 dfg' }
+      specify { expect(scan).to eq ['4111 1111 1111 1111'] }
+    end
+
     context 'a value that contains repeated valid credit card numbers' do
       let(:value) { 'cc1 4111 1111 1111 1111 cc2 4111 1111 1111 1111 123' }
       specify { expect(scan).to eq ['4111 1111 1111 1111', '4111 1111 1111 1111'] }