Error while building restructured documentation

[pradyunsg]

Problem

• This is a case of user error -- specifying the man page location in an incorrect manner. I'm getting a traceback instead of a helpful message here.

Procedure to reproduce the problem

git clone -b sphinx-error --single-branch https://github.com/pradyunsg/pip.git
cd pip
tox -e docs

Error logs / results

# Sphinx version: 1.7.7
# Python version: 3.6.5 (CPython)
# Docutils version: 0.14 
# Jinja2 version: 2.10
# Last messages:
#   done
#   
#   checking consistency...
#   
#   done
#   
#   writing...
#   
#   pip.1 {
#   
# Loaded extensions:
#   alabaster (0.7.11) from /Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/alabaster/__init__.py
#   sphinx.ext.extlinks (1.7.7) from /Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/sphinx/ext/extlinks.py
#   pip_sphinxext (unknown version) from /Users/pradyunsg/Projects/pip/docs/pip_sphinxext.py
#   sphinx.ext.intersphinx (1.7.7) from /Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/sphinx/ext/intersphinx.py
Traceback (most recent call last):
  File "/Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/sphinx/cmdline.py", line 304, in main
    app.build(args.force_all, filenames)
  File "/Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/sphinx/application.py", line 331, in build
    self.builder.build_update()
  File "/Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/sphinx/builders/__init__.py", line 337, in build_update
    self.build(['__all__'], to_build)
  File "/Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/sphinx/builders/__init__.py", line 403, in build
    self.write(docnames, list(updated_docnames), method)
  File "/Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/sphinx/builders/manpage.py", line 87, in write
    tree = self.env.get_doctree(docname)
  File "/Users/pradyunsg/Projects/pip/.tox/docs/lib/python3.6/site-packages/sphinx/environment/__init__.py", line 786, in get_doctree
    with open(doctree_filename, 'rb') as f:
FileNotFoundError: [Errno 2] No such file or directory: '/Users/pradyunsg/Projects/pip/.tox/docs/tmp/doctrees/man/man/index.doctree'

Expected results

A better error message.

Reproducible project / your project

• Provided above.

Environment info

• OS: MacOS High Sierra
• Python version: 2.7 or 3.6
• Sphinx version: 1.7.7

---

What I'm trying to do: Use a single conf.py file to build both html and man pages, which are in their own dedicated sub-directories; which both use a custom plugin from the same directory as conf.py.

[tk0miya]

Thank you for reporting.
I reproduced the error if man_pages option contains invalid docname.

[tk0miya]

I added warning at #5330.
Thank you for reporting.

[pradyunsg]

Thanks for the super quick fix! :)