diff --git a/lib/pry/helpers/module_introspection_helpers.rb b/lib/pry/helpers/module_introspection_helpers.rb
index 96c374ba..7d11a07d 100644
--- a/lib/pry/helpers/module_introspection_helpers.rb
+++ b/lib/pry/helpers/module_introspection_helpers.rb
@@ -31,7 +31,7 @@ class Pry
           :method
         elsif Pry::WrappedModule.from_str(input, target)
           :module
-        elsif target.eval("defined? #{input} ") =~ /variable|constant/
+        elsif target.eval("defined?(#{input})") =~ /variable|constant/
           :variable_or_constant
         elsif find_command(input)
           :command
diff --git a/test/test_default_commands/test_show_source.rb b/test/test_default_commands/test_show_source.rb
index 37daeab3..5810b5ed 100644
--- a/test/test_default_commands/test_show_source.rb
+++ b/test/test_default_commands/test_show_source.rb
@@ -89,6 +89,11 @@ if !mri18_and_no_real_source_location?
       mock_pry(binding, "show-source c.new.method").should =~ /98/
     end
 
+    it "should not show the source when a non-extant method is requested" do
+      c = Class.new{ def method; 98; end }
+      mock_pry(binding, "show-source c#wrongmethod").should =~ /could not be found/
+    end
+
     it "should find instance_methods even if the class has an override instance_method method" do
       c = Class.new{
         def method;