helpful-function doesn't show documentation

[DamienCassou]

When I type M-x helpful-function RET shell-quote-argument, I don't get the documentation of the function, except through it's source code. Is that expected? I would like a properly formatted documentation of each function so I can use helpful-function as a drop-in replacement for C-h f.

[DamienCassou]

Left is helpful-function, right is describe-function.

[Wilfred]

Nope, that's not expected. Every function should show its documentation.

I can't actually reproduce this:

I'd initially guessed the issue was autoloading, but I'd expect to see 'this function has not been loaded' in the *Help* buffer if autoloading was the cause.

Are you seeing this with other functions?

[DamienCassou]

I cannot reproduce anymore. I will reopen when and if it comes back. Sorry for the noise.

[Wilfred]

I have an idea what happened here.

Earlier versions of Helpful only supported functions, so buffers only stored the symbol. Now that we support both variables and functions, there's a helpful--callable-p that needs to be set.

I'm guessing that you reloaded an existing results buffer after upgrading? That would have had helpful--callable-p as nil, so it would be trying to show the docstring of a variable called shell-quote-argument.