1 files changed, 3 insertions, 3 deletions
diff --git a/lib/rubygems/specification_policy.rb b/lib/rubygems/specification_policy.rb
index 38724c3bde..03d7e92be5 100644
--- a/lib/rubygems/specification_policy.rb
+++ b/lib/rubygems/specification_policy.rb
@@ -125,7 +125,7 @@ class Gem::SpecificationPolicy
 
     metadata.each do |key, value|
       entry = "metadata['#{key}']"
-      if !key.kind_of?(String)
+      if !key.is_a?(String)
         error "metadata keys must be a String"
       end
 
@@ -133,7 +133,7 @@ class Gem::SpecificationPolicy
         error "metadata key is too large (#{key.size} > 128)"
       end
 
-      if !value.kind_of?(String)
+      if !value.is_a?(String)
         error "#{entry} value must be a String"
       end
 
@@ -343,7 +343,7 @@ duplicate dependency on #{dep}, (#{prev.requirement}) use:
               String
     end
 
-    unless Array === val && val.all? {|x| x.kind_of?(klass) }
+    unless Array === val && val.all? {|x| x.is_a?(klass) }
       error "#{field} must be an Array of #{klass}"
     end
   end