check for no links in link file and fail if not pull request

build/main.sh

@@ -27,6 +27,9 @@ if [ "$TRAVIS_BRANCH" == "master" ]; then
         echo "link validation failed!"
         exit 1
     else
+        if [ "$TRAVIS_PULL_REQUEST" == "false" ]; then
+            echo "no links to check on $TRAVIS_BRANCH branch - script failure!"
+        fi
         echo "link validation passed!"
     fi
 fi

build/validate_links.rb

@@ -17,6 +17,10 @@ raw_links.each do |link|
         links.push(link)
     end
 end
+if links.length <= 0
+    puts "no links to check"
+    exit(0)
+end
 fails = []
 # Fail on any duplicate elements
 dup = links.select{|element| links.count(element) > 1}