Python-Markdown 3.4 Release Notes

Python-Markdown version 3.4 supports Python versions 3.7, 3.8, 3.9, 3.10 and PyPy3.

Backwards-incompatible changes

The tables extension now uses a style attribute instead of an align attribute for alignment.

The HTML4 spec specifically deprecates the use of the align attribute and it does not appear at all in the HTML5 spec. Therefore, by default, the tables extension will now use the style attribute (setting just the text-align property) in td and th blocks.

The former behavior is available by setting the use_align_attribute configuration option to True when enabling the extension.

For example, to configure the old align behavior:

from markdown.extensions.tables import TableExtension

markdown.markdown(src, extensions=[TableExtension(use_align_attribute=True)])

Backslash unescaping moved to Treeprocessor (#1131).

Unescaping backslash escapes has been moved to a Treeprocessor, which enables proper HTML escaping during serialization. However, it is recognized that various third-party extensions may be calling the old class at postprocessors.UnescapePostprocessor. Therefore, the old class remains in the code base, but has been deprecated and will be removed in a future release. The new class treeprocessors.UnescapeTreeprocessor should be used instead.

Previously deprecated objects have been removed

Various objects were deprecated in version 3.0 and began raising deprecation warnings (see the version 3.0 release notes for details). Any of those objects which remained in version 3.3 have been removed from the code base in version 3.4 and will now raise errors. The relevant objects are listed below.

Deprecated Object Replacement Object
markdown.version markdown.__version__
markdown.version_info markdown.__version_info__
markdown.util.etree xml.etree.ElementTree
markdown.util.string_type str
markdown.util.text_type str
markdown.util.int2str chr
markdown.util.iterrange range
markdown.util.isBlockLevel markdown.Markdown().is_block_level
markdown.util.Processor().markdown markdown.util.Processor().md
markdown.util.Registry().__setitem__ markdown.util.Registry().register
markdown.util.Registry().__delitem__ markdown.util.Registry().deregister
markdown.util.Registry().add markdown.util.Registry().register

In addition, the md_globals parameter of Markdown.extensions.Extension.extendMarkdown() is no longer recognized as a valid parameter and will raise an error if provided.

New features

The following new features have been included in the 3.4 release:

  • Some new configuration options have been added to the footnotes extension (#1218):

    • Small refactor of the BACKLINK_TITLE option; The use of format() instead of “old” %d formatter allows one to specify text without the need to have the number of the footnote in it (like footnotes on Wikipedia for example). The modification is backward compatible so no configuration change is required.

    • Addition of a new option SUPERSCRIPT_TEXT that allows one to specify a custom placeholder for the footnote itself in the text. Ex: [{}] will give <sup>[1]</sup>, ({}) will give <sup>(1)</sup>, or by default, the current behavior: <sup>1</sup>.

  • The Table of Contents extension now accepts a toc_class parameter which can be used to set the CSS class(es) on the <div> that contains the Table of Contents (#1224).

  • The CodeHilite extension now supports a pygments_formatter option that can be set to a custom formatter class (#1187).

    • If pygments_formatter is set to a string (ex: 'html'), Pygments’ default formatter by that name is used.
    • If pygments_formatter is set to a formatter class (or any callable which returns a formatter instance), then an instance of that class is used.

    The formatter class is now passed an additional option, lang_str, to denote the language of the code block (#1258). While Pygments’ built-in formatters will ignore the option, a custom formatter assigned to the pygments_formatter option can make use of the lang_str to include the code block’s language in the output.

Bug fixes

The following bug fixes are included in the 3.4 release:

  • Extension entry-points are only loaded if needed (#1216).
  • Added additional checks to the <pre><code> handling of PrettifyTreeprocessor (#1261, #1263).