If module named "modules",it will get wrong content

[ghost]

Problem

If module named "modules",it will got wrong content.

dev
===

.. toctree::
   :maxdepth: 4

   conf
   handlers

Title "dev" is the directory name which I want to using sphinx to generating API documentation.

"conf" / "handlers" and "modules" in the same directory("dev").Directory structure like:

dev
├── conf
│   ├── a
│   └── b
├── handlers
│   ├── c
│   └── d
├── modules
│   ├── e
│   └── f

But,if rename "modules" to "module",it will work fine:

module package
==============

Submodules
----------

module.e
---------------------------

.. automodule:: module.e
    :members:
    :undoc-members:
    :show-inheritance:

Expected results

Do it no matter module's name.

Reproducible project / your project

Make a directory named "modules",and using sphinx-apidoc command to parsing it.

Environment info

• OS: Ubuntu18.04 LTS
• Python version:3.6.5
• Sphinx version:1.7.8

[tk0miya]

This is minimum reproducible steps:

$ ls
$ touch modules.py
$ sphinx-apidoc -o docs .
Creating file docs/modules.rst.
File docs/modules.rst already exists, skipping.

modules.rst is a default filename of index file which apidoc generates. So it is conflicted with target python module.

[tk0miya]

I just added --tocfile option for renaming modules.rst (see #5375).
Thank you for reporting!