Raise ConfigError for missing newsfragment directory

[altendky]

Fixes #85

[codecov-io]

Codecov Report

Merging #298 (7e0be3e) into master (6023801) will increase coverage by 0.10%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #298      +/-   ##
==========================================
+ Coverage   95.47%   95.57%   +0.10%     
==========================================
  Files          20       20              
  Lines        1060     1085      +25     
  Branches      104      105       +1     
==========================================
+ Hits         1012     1037      +25     
  Misses         27       27              
  Partials       21       21              

Impacted Files	Coverage Δ
src/towncrier/_builder.py	94.28% <100.00%> (+0.43%)	⬆️
src/towncrier/test/test_build.py	100.00% <100.00%> (ø)

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[adiroiban]

Thanks for working on fixing this bug.

I am -1 on this.

I think that is correct to not have towcrier create directories.

But I think that the error should not be ignored.

I am running towncrier draft as part of by continuous testing.
I want to see an error. For example if I have a typo in the path.

So instead of ignoring, just raise a ConfigError with a message that the news fragment couldn't be retrieved. It might be a missing path, it might be an OS permission error.

Just show a message like: "Failed to list the news fragment files. OS_ERROR_HERE"

And people should know what is wrong from the OS ERROR message.

[adiroiban]

My view now

[adiroiban]

For the title of PR, this PR is ok.

I would prefer to also see a non-zero exit code implemented in this PR :)

But this can be merged, assuming that we have a follow up issue for the non-zero exit code.

Thanks!

[adiroiban]

I am not sure what is going on here.

I guess that this is just a TODO due to some strange code in Click, and in the change we will have a non-zero exit code here.

Suggested change

	# This should fail
	self.assertEqual(result.exit_code, 0)
	# For now, exit code is zero, but it should be non-zero.
	# See: LINK TO ISSUE
	self.assertEqual(result.exit_code, 0)

[altendky]

Let's disregard my comment, I'll remove it. Do you want the pre-existing behavior of creating output with 'no significant changes' as the text and a zero exit code? Or, are we just confusing each other starting with my bad comment I left laying around.

[altendky]

Looks like the comment may have been a copy/paste error from the test after this.

[altendky]

Kick CI to watch try to observe codecov responses a bit.

[adiroiban]

Merge it :) Thanks!