Standardize the way we check for and display form errors

- Some views had a "Close" button. We've removed this, because we don't
  want users accidentally hiding the validation errors and not knowing
  what needs to be fixed.
- Some views used `li`, some used `p`, some used `span`. We've
  standardized on `li`.
- Some views only showed the first error. We've standardized on showing
  all of them.
- Some views added an `#error_explanation` div, which we've made
  standard.

1 files changed, 18 insertions, 0 deletions

diff --git a/app/helpers/form_helper.rb b/app/helpers/form_helper.rb
new file mode 100644
index 00000000000..6a43be2cf3e
--- /dev/null
+++ b/app/helpers/form_helper.rb
@@ -0,0 +1,18 @@
+module FormHelper
+  def form_errors(model)
+    return unless model.errors.any?
+
+    pluralized = 'error'.pluralize(model.errors.count)
+    headline   = "The form contains the following #{pluralized}:"
+
+    content_tag(:div, class: 'alert alert-danger', id: 'error_explanation') do
+      content_tag(:h4, headline) <<
+      content_tag(:ul) do
+        model.errors.full_messages.
+          map { |msg| content_tag(:li, msg) }.
+          join.
+          html_safe
+      end
+    end
+  end
+end