Preview different from final output

[fschulze]

As mentioned in #97 I get different output from preview to final. Now I was able to reproduce it.

The template:

{% for section in sections %}
{% set underline = "-" %}
{% if section %}
{{section}}
{{ underline * section|length }}{% set underline = "~" %}

{% endif %}
{% if sections[section] %}
{% for category, val in definitions.items() if category in sections[section] %}
{% if definitions[category]['name'] %}

{{ definitions[category]['name'] }}
{{ underline * definitions[category]['name']|length }}
{% endif %}

{% if definitions[category]['showcontent'] %}
{% for text, values in sections[section][category]|dictsort(by='value') %}
- {{ text }}

{% endfor %}
{% else %}
- {{ sections[section][category]['']|sort|join(', ') }}


{% endif %}
{% if sections[section][category]|length == 0 %}

No significant changes.


{% else %}
{% endif %}
{% endfor %}
{% else %}

No significant changes.


{% endif %}
{% endfor %}

The pyproject.toml:

[tool.towncrier]
package = "project"
filename = "src/project/docs/changes.rst"
directory = "changes/"
title_format = "{version} - {project_date}"
template = "changes/_template.rst"

  [[tool.towncrier.type]]
  directory = "change"
  name = ""
  showcontent = true

  [[tool.towncrier.type]]
  directory = "migration"
  name = "Contains migration"
  showcontent = true

  [[tool.towncrier.type]]
  directory = "solr"
  name = "Requires Solr update"
  showcontent = true

The draft looks like this:

% towncrier --draft
Loading template...
Finding news fragments...
Rendering news fragments...
Draft only -- nothing has been written.
What is seen below is what would be written.

10.0 - 2018-01-01
=============


- bla

%

The changes file afterwards looks like this:

10.0 - 2018-01-01
=============

- bla


9.0 - ...
=====

Notice the difference in newlines below the equal signs and after the changelog entry. The goal is to have one after the equal signs and two after the changes before the previous version.

[htgoebel]

This is simply caused by a new-line added between top_line and rendered text in draft-mode: https://github.com/hawkowl/towncrier/blob/24f825c371db516a1579a22119b478b0d10a2ab5/src/towncrier/__init__.py#L133.

[altendky]

@fschulze, is below satisfactory? It shows that present master doesn't create the double blank line after the === line or --- line but depending on how you count newlines after the actual fragment you might say there's only one?

$ ../venv/bin/towncrier build --draft
Loading template...
Finding news fragments...
Rendering news fragments...
Draft only -- nothing has been written.
What is seen below is what would be written.

towncrier 19.3.0 (2020-12-13)
=============================

Features
--------

- new content (`#2 <https://github.com/hawkowl/towncrier/issues/2>`_)

$

[fschulze]

I just tried with ef1be45 and still get the same output as originally posted. I also wonder what the build is doing in your invocation, I get Error: Got unexpected extra argument (build) with that.

[altendky]

As of 19.9.0rc1 there are subcommands for build, check, and create. I'll look into this again. Thanks for the quick followup.

[altendky]

Ok, maybe I got it this time over in #303.

[fschulze]

Why don't the subcommands work when using master or your branch in #303 then?

[altendky]

Given that you said you were able to confirm the fix, I dunno... Could you share your terminal session either in a new ticket here or via https://bpaste.net/ or similar over in #twisted on Freenode (IRC)?

[fschulze]

Both master and your branch from #303 are still at 19.2.0, I only found https://github.com/twisted/towncrier/tree/hawkowl/release-19.09 which seems to be newer, but there I get the same:

% towncrier build --draft
Usage: towncrier build [OPTIONS]

Error: Got unexpected extra argument (build)

[webknjaz]

FTR this regression badly influences how https://github.com/sphinx-contrib/sphinxcontrib-towncrier works. It uses --draft internally to get the unreleased changelog section preview and with the recent Towncrier release, it now doesn't get any title, only the underline that is coming from the template. If I add that {{ top_line }} into the template, then --draft works as expected but the regular run has a nasty double-version title.