Email addresses containing underscore and surrounded by <> are filtered out when filter_html is enabled

[marius-balteanu]

A Redmine user reported that Markdown doesn't recognize some email addresses.

I've added two test cases to illustrate the reported problem. Unfortunately, I don't have the required skills to fix the issue.

  def test_filter_html_doesnt_filter_email_addresses_surrounded_by_tags
    markdown = "<[email protected]>"
    output   = render(markdown, with: [:filter_html, :autolink])

    assert_equal "<p><a href=\"mailto:[email protected]\">[email protected]</a></p>", output
  end

  def test_filter_html_doesnt_filter_email_addresses_surrounded_by_tags_and_containing_underscore
    markdown = "<[email protected]>"
    output   = render(markdown, with: [:filter_html, :no_intra_emphasis, :autolink])

    assert_equal "<p><a href=\"mailto:[email protected]\">[email protected]</a></p>", output
  end

The second test fails because [email protected] is considered somehow an HTML tag and it is filtered out.

/vagrant/redcarpet/test/html_render_test.rb:54:in `test_filter_html_doesnt_filter_email_addresses_surrounded_by_tags_and_containing_underscore'
     51:     markdown = "<[email protected]>"
     52:     output   = render(markdown, with: [:filter_html, :no_intra_emphasis, :autolink])
     53: 
  => 54:     assert_equal "<p><a href=\"mailto:[email protected]\">[email protected]</a></p>", output
     55:   end
     56: 
     57:   def test_that_no_image_flag_works
<"<p><a href=\"mailto:[email protected]\">[email protected]</a></p>"> expected but was
<"">
Failure: test_filter_html_doesnt_filter_email_addresses_surrounded_by_tags_and_containing_underscore(HTMLRenderTest)
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Finished in 0.30313018 seconds.
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131 tests, 190 assertions, 1 failures, 0 errors, 0 pendings, 0 omissions, 0 notifications
99.2366% passed