Fix expression filter descriptions in selector failure messages

lib/capybara/selector/selector.rb

@@ -251,7 +251,7 @@ module Capybara
     end
 
     def describe_all_expression_filters(**opts)
-      expression_filters.map { |ef| " with #{ef} #{opts[ef]}" if opts.key?(ef) }.join
+      expression_filters.keys.map { |ef| " with #{ef} #{opts[ef]}" if opts.key?(ef) }.join
     end
 
     def find_by_attr(attribute, value)

spec/selector_spec.rb

@@ -27,6 +27,7 @@ RSpec.describe Capybara do
             <input type="text" name="form[my_text_input]" placeholder="my text" id="my_text_input"/>
             <input type="file" id="file" class=".special file"/>
             <input type="hidden" id="hidden_field" value="this is hidden"/>
+            <input type="submit" value="click me" title="submit button"/>
             <a href="#">link</a>
             <fieldset></fieldset>
             <select id="select">
@@ -193,6 +194,20 @@ RSpec.describe Capybara do
           expect(string.find(:option, disabled: false, selected: false).value).to eq 'a'
         end
       end
+
+      describe ":button selector" do
+        it "finds by value" do
+          expect(string.find(:button, 'click me').value).to eq 'click me'
+        end
+
+        it "finds by title" do
+          expect(string.find(:button, 'submit button').value).to eq 'click me'
+        end
+
+        it "includes non-matching parameters in failure message" do
+          expect { string.find(:button, 'click me', title: 'click me') }.to raise_error(/with title click me/)
+        end
+      end
     end
   end
 end