resolves #217 add support for Unicode characters in chapter IDs

CHANGELOG.adoc

@@ -8,6 +8,7 @@ For a detailed view of what has changed, refer to the {uri-repo}/commits/master[
 == Unreleased
 
 * drop unused dependencies: thread_safe, concurrent-ruby (#234)
+* add support for Unicode characters in chapter IDs (#217)
 * fix sample-book to be a valid book (#196)
 * fix the (in)famous `undefined method `to_ios'` when given a document that doesn't follow asciidoctor-epub3 rules (#7)
 

lib/asciidoctor-epub3/packager.rb

@@ -582,7 +582,16 @@ def package options = {}
         ::FileUtils.mkdir_p dest unless ::File.directory? dest
 
         epub_file = fmt == :kf8 ? %(#{::Asciidoctor::Helpers.rootname target}-kf8.epub) : target
-        builder.generate_epub epub_file
+
+        prev_zip_unicode = ::Zip.unicode_names
+        begin
+          # Let's hope there are no parallel threads running while we're messing with global variable
+          ::Zip.unicode_names = true
+          builder.generate_epub epub_file
+        ensure
+          ::Zip.unicode_names = prev_zip_unicode
+        end
+
         puts %(Wrote #{fmt.upcase} to #{epub_file}) if $VERBOSE
         if options[:extract]
           extract_dir = epub_file.sub EpubExtensionRx, ''

spec/converter_spec.rb

@@ -28,5 +28,24 @@
           attributes: { 'ebook-format' => 'mobi' }
       expect(File).to exist(outfile)
     end
+
+    it 'converts chapter with unicode title to unicode filename' do
+      infile = fixture_file 'unicode/spine.adoc'
+      outfile = temp_file 'unicode.epub'
+      Asciidoctor.convert_file infile,
+          to_file: outfile,
+          backend: 'epub3',
+          header_footer: true,
+          mkdirs: true
+      prev_zip_encoding = Zip.force_entry_names_encoding
+      begin
+        Zip.force_entry_names_encoding = 'UTF-8'
+        Zip::File.open outfile do |zip|
+          expect(zip.find_entry('OEBPS/test-é.xhtml')).not_to be_nil
+        end
+      ensure
+        Zip.force_entry_names_encoding = prev_zip_encoding
+      end
+    end
   end
 end

spec/fixtures/unicode/reference.adoc

@@ -0,0 +1 @@
+= Test é

spec/fixtures/unicode/spine.adoc

@@ -0,0 +1,6 @@
+= Unicode book
+:doctype: book
+:idprefix:
+:idseparator: -
+
+include::reference.adoc[]