1 files changed, 9 insertions, 1 deletions
diff --git a/spec/ruby/library/erb/new_spec.rb b/spec/ruby/library/erb/new_spec.rb
index 0497bb7e15..33a3952dd4 100644
--- a/spec/ruby/library/erb/new_spec.rb
+++ b/spec/ruby/library/erb/new_spec.rb
@@ -31,11 +31,19 @@ END
 
   it "compiles eRuby script into ruby code when trim mode is 0 or not specified" do
     expected = "<ul>\n\n\n\n<li>1</li>\n\n\n\n<li>2</li>\n\n\n\n<li>3</li>\n\n\n</ul>\n"
-    [0, '', nil].each do |trim_mode|
+    [0, nil].each do |trim_mode|
       ERBSpecs.new_erb(@eruby_str, trim_mode: trim_mode).result.should == expected
     end
   end
 
+  ruby_version_is "2.6" do
+    it "warns invalid trim_mode" do
+      lambda do
+        ERBSpecs.new_erb(@eruby_str, trim_mode: '')
+      end.should output(nil, /Invalid ERB trim mode/)
+    end
+  end
+
   it "removes '\n' when trim_mode is 1 or '>'" do
     expected = "<ul>\n<li>1</li>\n<li>2</li>\n<li>3</li>\n</ul>\n"
     [1, '>'].each do |trim_mode|