vim cannot check markdown spell

Question

I do not mean to let vim check my spell automatically, so please do not tell me to add a autocmd ... line in my vimrc.

I created a .md file and put these contents in it:

8) good fftowndn

Then I run the command :setlocal spell! in the normal mode, but this does not check the wrong spell token of fftowndn in my contents. However, the spell checking works well if I comment the contents.

How could I make spell checking work with .md please ?

Edit: in other file types such as txt file, after I run :setlocal spell!, the error tokens of fftowndn will be highlighted but here I do not see this highlight in the markdown file.

Edit2:

I come to find that the spell checking works well for the title marked with #, ##, ..., ######, and from ####### on there will be no checking. It is the same with my markdown contents. If I do not mark my contents, there will be no spell checkings.

Edit3:
after various trying, I got to find the problem is likely to be with this line in my .vimrc:

let g:markdown_fenced_languages = [
        \ 'vim',
        \  'html',
        \  'css',
        \  'erb=eruby',
        \  'go',
        \  'java',
        \  'javascript',
        \  'js=javascript',
        \  'json=javascript',
        \  'ruby',
        \  'sass',
        \  'sql',
        \  'xml',
        \  'cpp',
        \  'python',
        \  'bash=sh',
        \  'cmake'
        \]

I just need markdown to show highlight for me code in the block between '```' and '```' pairs, but I did not expect it will affect my spell check, how could I solve this?

Answer 1

You have two possible workarounds:

1. Change the order of entries in g:markdown_fenced_languages so that 'java' is mentioned before 'html'.
2. Set the global variable java_ignore_javadoc to some value (like let java_ignore_javadoc=1)

Background:

The Java syntax file includes the HTML syntax file to do highlighting of HTML in javadoc comments. After this include, it sets syntax spell default to prevent spell checking on all texts. See here.

By disabling spell checking for "all text" it disables the spell checking for markdown text.

When the global variable java_ignore_javadoc is set (workaround 2), the java syntax does not include the html syntax file and does not reset the syntax spell setting. Then spell checking works, but special highlighting for javadoc is disabled.

By reloading the html syntax after the java syntax (workaround 1), the setting syntax spell default (from java) is again overwritten with syntax spell toplevel from the html syntax. Hence spell checking works again.