1 files changed, 98 insertions, 0 deletions
diff --git a/guides/w3c_validator.rb b/guides/w3c_validator.rb
new file mode 100644
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+++ b/guides/w3c_validator.rb
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+# frozen_string_literal: true
+
+# ---------------------------------------------------------------------------
+#
+# This script validates the generated guides against the W3C Validator.
+#
+# Guides are taken from the output directory, from where all .html files are
+# submitted to the validator.
+#
+# This script is prepared to be launched from the guides directory as a rake task:
+#
+# rake guides:validate
+#
+# If nothing is specified, all files will be validated, but you can check just
+# some of them using this environment variable:
+#
+#   ONLY
+#     Use ONLY if you want to validate only one or a set of guides. Prefixes are
+#     enough:
+#
+#       # validates only association_basics.html
+#       rake guides:validate ONLY=assoc
+#
+#     Separate many using commas:
+#
+#       # validates only association_basics.html and command_line.html
+#       rake guides:validate ONLY=assoc,command
+#
+# ---------------------------------------------------------------------------
+
+require "w3c_validators"
+include W3CValidators
+
+module RailsGuides
+  class Validator
+    def validate
+      # https://github.com/w3c-validators/w3c_validators/issues/25
+      validator = NuValidator.new
+      STDOUT.sync = true
+      errors_on_guides = {}
+
+      guides_to_validate.each do |f|
+        begin
+          results = validator.validate_file(f)
+        rescue Exception => e
+          puts "\nCould not validate #{f} because of #{e}"
+          next
+        end
+
+        if results.errors.length > 0
+          print "E"
+          errors_on_guides[f] = results.errors
+        else
+          print "."
+        end
+      end
+
+      show_results(errors_on_guides)
+    end
+
+    private
+      def guides_to_validate
+        guides = Dir["./output/*.html"]
+        guides.delete("./output/layout.html")
+        guides.delete("./output/_license.html")
+        guides.delete("./output/_welcome.html")
+        ENV.key?("ONLY") ? select_only(guides) : guides
+      end
+
+      def select_only(guides)
+        prefixes = ENV["ONLY"].split(",").map(&:strip)
+        guides.select do |guide|
+          prefixes.any? { |p| guide.start_with?("./output/#{p}") }
+        end
+      end
+
+      def show_results(error_list)
+        if error_list.size == 0
+          puts "\n\nAll checked guides validate OK!"
+        else
+          error_summary = error_detail = ""
+
+          error_list.each_pair do |name, errors|
+            error_summary += "\n  #{name}"
+            error_detail += "\n\n  #{name} has #{errors.size} validation error(s):\n"
+            errors.each do |error|
+              error_detail += "\n    " + error.to_s.delete("\n")
+            end
+          end
+
+          puts "\n\nThere are #{error_list.size} guides with validation errors:\n" + error_summary
+          puts "\nHere are the detailed errors for each guide:" + error_detail
+        end
+      end
+  end
+end
+
+RailsGuides::Validator.new.validate