markdown-edit-code-block fails with "funcall-interactively: Wrong type argument: integer-or-marker-p, nil"

[vaaas]

I believe this may be related to #563.

I have managed to reproduce it. The following consistently fails on my machine, but only on the second time I call markdown-edit-code-block

Some text.

```html
<template>
		<SomeElement foo='bar' alice='bob'>
			<table class='foobarbazfoo test.test'>
				<thead>
					<tr>
						<th>Test</th>
						<th>Test</th>
					</tr>
				</thead>

				<tbody>
					<tr class='test test foo_bar.test'>
						<td><input prop-name='link.text'/></td>
					</tr>
				</tbody>
			</table>

			<div/>
		</SomeElement>
</template>
```

I've reproduced it with emacs -q.

GNU Emacs 27.2 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.27, cairo version 1.17.4) of 2021-03-26

Arch Linux

markdown-mode 20210904.733

[syohex]

Thanks for reporting issue. However I cannot reproduce. Could you tell us how to reproduce this issue in more detail ? reproduce steps, cursor position etc.

[vaaas]

Sure thing!

1. Use the attached snippet: snippet.md
2. Open it with emacs: emacs -Q snippet.md
3. Run the following eval-expression to load markdown-mode: M-: (progn (require 'package) (package-initialize) (markdown-mode)) RET
4. Move to the first LESS-THAN SIGN: M-x search-forward RET < RET
5. Edit the code block: M-x markdown-edit-code-block RET
6. Write something.
7. Commit. M-x edit-indirect-commit RET
8. Edit the come block again: M-x markdown-edit-code-block RET
9. Edit fails.

[syohex]

#664 fixes error case, however it does not fix underlying problem.