Fix TestCorporateIdentityTemplateList in Python 2.

Errors were being raised for returning `None` in Python 2
(due to a missing else branch) and for re-encoding bytes
in Python 2.

I changed the code to use str2bytes in the cases where bytes
are expected.

bt5/erp5_corporate_identity/SkinTemplateItem/portal_skins/erp5_corporate_identity/WebPage_viewAsBook.py

@@ -36,6 +36,7 @@ import re
 import six
 
 from Products.PythonScripts.standard import html_quote
+from Products.ERP5Type.Utils import str2bytes
 from base64 import b64encode
 
 blank = ''
@@ -359,22 +360,22 @@ elif book_format == "pdf":
   )
 
   # ================ encode and build cloudoo elements =========================
-  header_embedded_html_data = book.Base_convertHtmlToSingleFile(book_head, allow_script=True).encode('utf-8')
+  header_embedded_html_data = str2bytes(book.Base_convertHtmlToSingleFile(book_head, allow_script=True))
   before_toc_data_list = [
-    b64encode(book.Base_convertHtmlToSingleFile(book_cover, allow_script=True).encode('utf-8')).decode(),
+    b64encode(str2bytes(book.Base_convertHtmlToSingleFile(book_cover, allow_script=True))).decode(),
   ]
   after_toc_data_list = []
   if book_include_history_table:
     before_toc_data_list.append(
-      b64encode(book.Base_convertHtmlToSingleFile(book_history, allow_script=True).encode('utf-8')).decode()
+      b64encode(str2bytes(book.Base_convertHtmlToSingleFile(book_history, allow_script=True))).decode()
     )
   #if book_include_reference_table:
   #  after_toc_data_list.append(
-  #    b64encode(book.Base_convertHtmlToSingleFile(book_references, allow_script=True).encode('utf-8')).decode()
+  #    b64encode(str2bytes(book.Base_convertHtmlToSingleFile(book_references, allow_script=True))).decode()
   #  )
   xsl_style_sheet_data = book_table_of_content.encode('utf-8')
-  embedded_html_data = book.Base_convertHtmlToSingleFile(book_content, allow_script=True).encode('utf-8')
-  footer_embedded_html_data = book.Base_convertHtmlToSingleFile(book_foot, allow_script=True).encode('utf-8')
+  embedded_html_data = str2bytes(book.Base_convertHtmlToSingleFile(book_content, allow_script=True))
+  footer_embedded_html_data = str2bytes(book.Base_convertHtmlToSingleFile(book_foot, allow_script=True))
   if margin_15mm:
     margin_top = 50
     margin_bottom = 25

bt5/erp5_web/SkinTemplateItem/portal_skins/erp5_web/Base_convertHtmlToSingleFile.py

@@ -28,6 +28,8 @@ mhtml_message = {
 }
 
 def main(data):
+  # type: (str) -> str
+  # Preserves input type (unicode or bytes)
   if isinstance(data, bytes):
     data = data.decode("utf-8")
   data = u"".join([fn(p) for fn, p in handleHtmlPartList(parseHtml(data))])

product/ERP5/bootstrap/erp5_core/DocumentTemplateItem/portal_components/document.erp5.TextDocument.py

@@ -42,7 +42,7 @@ from string import Template
 from erp5.component.mixin.CachedConvertableMixin import CachedConvertableMixin
 from erp5.component.mixin.BaseConvertableFileMixin import BaseConvertableFileMixin
 from Products.ERP5Type.mixin.text_content_history import TextContentHistoryMixin
-from Products.ERP5Type.Utils import guessEncodingFromText, bytes2str
+from Products.ERP5Type.Utils import guessEncodingFromText, bytes2str, str2bytes
 
 from lxml import html as etree_html
 from lxml import etree
@@ -428,8 +428,7 @@ class TextDocument(CachedConvertableMixin, BaseConvertableFileMixin, TextContent
         data = self._baseGetTextContent()
       else:
         data = self._baseGetTextContent(default)
-      if not isinstance(data, bytes):
-        return data.encode('utf-8')
+      return str2bytes(data)
     else:
       if default is _MARKER:
         return File.getData(self)