don't error on course export if the course name is too long

test plan:
* make a course with a name as long as you can
(255 characters)
* confirm that you can export it successfully

fixes #CNVS-3549

Change-Id: I34dc93ba4578bf67b7155138beee231adeb5d4ef
Reviewed-on: https://gerrit.instructure.com/17376
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Jeremy Stanley <jeremy@instructure.com>
QA-Review: Jeremy Stanley <jeremy@instructure.com>

app/models/wiki.rb

@@ -98,7 +98,11 @@ class Wiki < ActiveRecord::Base
       # TODO i18n
       t :default_course_wiki_name, "%{course_name} Wiki", :course_name => nil
       t :default_group_wiki_name, "%{group_name} Wiki", :group_name => nil
-      context.wiki = wiki = Wiki.create!(:title => "#{context.name} Wiki")
+
+      self.extend TextHelper
+      name = truncate_text(context.name, {:max_length => 200, :ellipsis => ''})
+
+      context.wiki = wiki = Wiki.create!(:title => "#{name} Wiki")
       context.save!
       wiki
     end

lib/cc/cc_exporter.rb

@@ -17,6 +17,8 @@
 #
 module CC
   class CCExporter
+    include TextHelper
+
     ZIP_DIR = 'zip_dir'
     
     attr_accessor :course, :user, :export_dir, :manifest, :zip_file, :for_course_copy
@@ -134,10 +136,11 @@ module CC
     end
 
     def create_zip_file
+      name = truncate_text(@course.name.to_url, {:max_length => 200, :ellipsis => ''})
       if @qti_only_export
-        @zip_name = "#{@course.name.to_url}-quiz-export.zip"
+        @zip_name = "#{name}-quiz-export.zip"
       else
-        @zip_name = "#{@course.name.to_url}-export.#{CCHelper::CC_EXTENSION}"
+        @zip_name = "#{name}-export.#{CCHelper::CC_EXTENSION}"
       end
       FileUtils::mkdir_p File.join(@export_dir, ZIP_DIR)
       @zip_path = File.join(@export_dir, ZIP_DIR, @zip_name)

spec/lib/cc/cc_exporter_spec.rb

@@ -397,5 +397,11 @@ describe "Common Cartridge exporting" do
       @manifest_doc.at_css('resource[href="course_settings/canvas_export.txt"]').should_not be_nil
       @zip_file.find_entry('course_settings/canvas_export.txt').should_not be_nil
     end
+
+    it "should not error if the course name is too long" do
+      @course.name = "a" * Course.maximum_string_length
+
+      run_export
+    end
   end
 end