circle.rb in danger-3.1.0

- old
+ new

@@ -38,10 +38,10 @@
       env.key? "CIRCLE_BUILD_NUM"
     end
 
     def self.validates_as_pr?(env)
       # This will get used if it's available, instead of the API faffing.
-      return true unless env["CI_PULL_REQUEST"].empty?
+      return true if env["CI_PULL_REQUEST"] && !env["CI_PULL_REQUEST"].empty?
 
       # Real-world talk, it should be worrying if none of these are in the environment
       return false unless ["CIRCLE_CI_API_TOKEN", "CIRCLE_PROJECT_USERNAME", "CIRCLE_PROJECT_REPONAME", "CIRCLE_BUILD_NUM"].all? { |x| env[x] && !env[x].empty? }
 
       # Uses the Circle API to determine if it's a PR otherwise