Vue - addon-docs does not work with render functions

[mattgreenfield]

Describe the bug
When adding addon-docs to a Vue component with a render function (and no ) I get the following error:
[vue-docgen-loader] failed to parse the component file with docgen-api: Cannot read property 'leadingComments' of null

The 'Docs' tab loads in the browser and shows the component in the iframe but does not show the component description and prop info.

Removing the render function and adding a fixes this.

To Reproduce
Steps to reproduce the behavior:

1. Add addon-docs to a Vue project
2. Add a story for a component with a render function
3. See error

Expected behavior
This should work just like any other component.
If that's not possible, maybe the warning could be better? "addon-docs does not support components with a render function"

Screenshots

System:
System:
OS: macOS Mojave 10.14.6
CPU: (4) x64 Intel(R) Core(TM) i5-7600 CPU @ 3.50GHz
Binaries:
Node: 10.15.0 - ~/.nvm/versions/node/v10.15.0/bin/node
npm: 6.13.7 - ~/Documents/ui-baseplate/node_modules/.bin/npm
Browsers:
Chrome: 79.0.3945.130
Firefox: 71.0
Safari: 13.0.5
npmPackages:
@storybook/addon-actions: ^5.3.7 => 5.3.10
@storybook/addon-backgrounds: ^5.3.7 => 5.3.10
@storybook/addon-docs: ^5.3.10 => 5.3.10
@storybook/addon-knobs: ^5.3.7 => 5.3.10
@storybook/addon-links: ^5.3.7 => 5.3.10
@storybook/addon-notes: ^5.3.7 => 5.3.10
@storybook/addon-storysource: ^5.3.7 => 5.3.10
@storybook/addon-viewport: ^5.3.7 => 5.3.10
@storybook/addons: ^5.3.7 => 5.3.10
@storybook/source-loader: ^5.3.7 => 5.3.10
@storybook/vue: ^5.3.7 => 5.3.10

[shilman]

@Aaron-Pool is this anything you know about?

[Aaron-Pool]

@shilman no, I'm fairly confident render functions are known to be working. At least the typical use case. @mattgreenfield any chance you could set up a minimal repro repo for debugging purposes?

[mattgreenfield]

Thanks for your time and help.

I've created a reduced test case and narrowed down the error a little (it's not render functions that's the problem).

I've opened a new issue here #9821

[mattgreenfield]

I've managed to reproduce this one and have raised an issue with vue-docgen here vue-styleguidist/vue-styleguidist#753