How do I disable intelligent indentation in HTML files?

Question

I've created a blank example.html file and I open it in Vim, and I add the following contents:

<div>

Still in insert mode, at the end of the line, if I press enter, the new line will automatically be indented for when I type <p>:

<div>
        <p>

Clearly, something knows that <div> expects children, which should be indented, and is indenting the following line automatically for me. What is enabling this? How do I disable this, without disabling other automatic indentation features like :set autoindent copyindent?

Note that :set smartindent? displays nosmartindent, so it's not that.

Answer 1

It turns out that Vim ships with a bunch of indent.vim files (enabled with :filetype indent on), including one for HTML. You can read help for it at :help html-indenting.

This HTML indent file sets indentexpr option to a function that knows how to parse HTML. When indentexpr is set, it overrules cindent and smartindent. If you want to disable it, run :set indentexpr=.

If you want to always disable it, put this in your .vimrc file:

au FileType html,htmldjango setlocal indentexpr=