Rails 5 tag helper with tag name in variable

Question

I am converting some older code which uses content_tag like this:

wrap_tag = 'p'
....
content_tag(wrap_tag, class: 'etc') do
  'some content'
end

which generates the expected

<p class="etc">
Some content
</div>

I'd now like to update to use the tag syntax, but I am having troubles with this:

wrap_tag = 'p'
...
tag wrap_tag, class: 'etc' do
  'some content'
end

Trying: tag.wrap_tag gives "<wrap-tag>some content</wrap-tag>"

Not unexpected, except that the underscore has become a hyphen.

Other variations:

• Using tag.p directly: <p>some content</p>
• Using tag.wrap_tag:<wrap-tag>some content</wrap-tag>
• Using tag.wrap_tag.to_sym:<wrap-tag></wrap-tag>
• Using tag wrap_tag: <p />
• Using tag wrap_tag.to_sym: <p />

Note: all the examples above included the do..content..end block shown initially.

Is there a way to have the tag name in a variable and include content?

Thanks

---

Trying the suggestion from jvillian to use send I find that

wrap_tag = 'p'
content = 'some text'
helper.tag.send(wrap_tag, content)

returns "some text", and generally returns the second and subsequent arguments.

---

It does seem, looking at actionview/helpers/tag_helper.rb, that the content_tag method checks for block_given? and tag doesn't.

But whyyyyyyyyy (not) I will have to read through the PR again to find out.

Answer 1

I find that if I do:

@arg = :div
tag.send @arg, class: 'etc' do 
  'some content'
end

...then I get:

<div class="etc">some content</div>

Similarly, if I do:

@arg = :section
tag.send @arg, class: 'etc' do 
  'some content'
end

...then I get:

<section class="etc">some content</section>

If, however, I do:

@arg = :p
tag.send @arg, class: 'etc' do 
  'some content'
end

...then I get:

{:class=>"etc"}

Which, obviously, is not what one expects. And, seems straight-up peculiar, because:

tag.p class: 'etc' do 
  'some content'
end

...gives:

<p class="etc">some content</p>

...which is all sunshine and lolipops.

Gremlins? One can only wonder.