blurb

Overview

blurb is a tool designed to rid CPython core development
of the scourge of Misc/NEWS conflicts.

The core concept: split Misc/NEWS into many
separate files that, when concatenated back together
in sorted order, reconstitute the original Misc/NEWS file.
After that, Misc/NEWS could be deleted from the CPython
repo and thereafter rendered on demand (e.g. when building
a release). When committing a change to CPython, the commit
process will write out a new file that sorts into the correct place,
using a filename unlikely to have a merge conflict.

blurb is a single command with a number of subcommands.
It's designed to be run inside a valid CPython (Git) repo,
and automatically uses the correct file paths.

You can install blurb from PyPI using pip. Alternatively,
simply add blurb to a directory on your path.

Files used by blurb

blurb uses a new directory tree called Misc/NEWS.d.
Everything it does is in there, except for possibly
modifying Misc/NEWS.

Under Misc/NEWS.d you'll find the following:

A single file for all news entries per previous revision,
named for the exact version number, with the extension .rst.
Example: Misc/NEWS.d/3.6.0b2.rst.
The next directory, which contains subdirectories representing
the various Misc/NEWS categories. Inside these subdirectories
are more .rst files with long, uninteresting, computer-generated
names. Example:
Misc/NEWS.d/next/Library/2017-05-04-12-24-06.gh-issue-25458.Yl4gI2.rst

blurb subcommands

Like many modern utilities, blurb has only one executable
(called blurb), but provides a diverse set of functionality
through subcommands. The subcommand is the first argument specified
on the command-line.

If you're a CPython contributor, you probably don't need to use
anything except blurb add — and you don't even need to specify
the add part.
(If no subcommand is specified, blurb assumes you meant blurb add.)
The other commands are only expected to be useful for CPython release
managers.

blurb help

blurb is self-documenting through the blurb help subcommand.
Run without any further arguments, it prints a list of all subcommands,
with a one-line summary of the functionality of each. Run with a
third argument, it prints help on that subcommand (e.g. blurb help release).

blurb add

blurb add adds a new Misc/NEWS entry for you.
It opens a text editor on a template; you edit the
file, save, and exit. blurb then stores the file
in the correct place, and stages it in Git for you.

The template for the blurb add message looks like this:

#
# Please enter the relevant GitHub issue number here:
#
.. gh-issue:

#
# Uncomment one of these "section:" lines to specify which section
# this entry should go in in Misc/NEWS.
#
#.. section: Security
#.. section: Core and Builtins
#.. section: Library
#.. section: Documentation
#.. section: Tests
#.. section: Build
#.. section: Windows
#.. section: macOS
#.. section: IDLE
#.. section: Tools/Demos
#.. section: C API

# Write your Misc/NEWS entry below.  It should be a simple ReST paragraph.
# Don't start with "- Issue #<n>: " or "- gh-issue<n>: " or that sort of stuff.
###########################################################################

Here's how you interact with the file:

Add the GitHub issue number for this commit to the
end of the .. gh-issue: line.
Uncomment the line with the relevant Misc/NEWS section for this entry.
For example, if this should go in the Library section, uncomment
the line reading #.. section: Library. To uncomment, just delete
the # at the front of the line.
Finally, go to the end of the file, and enter your NEWS entry.
This should be a single paragraph of English text using
simple reST markup.

When blurb add gets a valid entry, it writes it to a file
with the following format:

Misc/NEWS.d/next/<section>/<datetime>.gh-issue-<issue_number>.<nonce>.rst

For example, a file added by blurb add might look like this::

Misc/NEWS.d/next/Library/2017-05-04-12-24-06.gh-issue-25458.Yl4gI2.rst

<section> is the section provided in the commit message.

<datetime> is the current UTC time, formatted as
YYYY-MM-DD-hh-mm-ss.

<nonce> is a hopefully-unique string of characters meant to
prevent filename collisions. blurb creates this by computing
the MD5 hash of the text, converting it to base64 (using the
"urlsafe" alphabet), and taking the first 6 characters of that.

This filename ensures several things:

All entries in Misc/NEWS will be sorted by time.
It is unthinkably unlikely that there'll be a conflict
between the filenames generated for two developers committing,
even if they commit in at the exact same second.

Finally, blurb add stages the file in git for you.

blurb merge

blurb merge recombines all the files in the
Misc/NEWS.d tree back into a single NEWS file.

blurb merge accepts only a single command-line argument:
the file to write to. By default, it writes to
Misc/NEWS (relative to the root of your CPython checkout).

Splitting and recombining the existing Misc/NEWS file
doesn't recreate the previous Misc/NEWS exactly. This
is because Misc/NEWS never used a consistent ordering
for the "sections" inside each release, whereas blurb merge
has a hard-coded preferred ordering for the sections. Also,
blurb aggressively reflows paragraphs to < 78 columns,
wheras the original hand-edited file occasionally had lines >
80 columns. Finally, blurb strictly uses gh-issue-<n>: to
specify issue numbers at the beginnings of entries, wheras
the legacy approach to Misc/NEWS required using Issue #<n>:.

blurb release

blurb release is used by the release manager as part of
the CPython release process. It takes exactly one argument,
the name of the version being released.

Here's what it does under the hood:

Combines all recently-added NEWS entries from
the Misc/NEWS.d/next directory into Misc/NEWS.d/<version>.rst.
Runs blurb merge to produce an updated Misc/NEWS file.

One hidden feature: if the version specified is ., blurb release
uses the name of the directory CPython is checked out to.
(When making a release I generally name the directory after the
version I'm releasing, and using this shortcut saves me some typing.)

The "next" directory

You may have noticed that blurb add adds news entries to
a directory called next, and blurb release combines those
news entries into a single file named with the version. Why
is that?

First, it makes naming the next version a late-binding decision.
If we are currently working on 3.6.5rc1, but there's a zero-day
exploit and we need to release an emergency 3.6.5 final, we don't
have to fix up a bunch of metadata.

Second, it means that if you cherry-pick a commit forward or
backwards, you automatically pick up the NEWS entry too. You
don't need to touch anything up — the system will already do
the right thing. If NEWS entries were already written to the
final version directory, you'd have to move those around as
part of the cherry-picking process.

Copyright

blurb is Copyright 2015-2018 by Larry Hastings.
Licensed to the PSF under a contributor agreement.

Changelog

See CHANGELOG.md.

Dependencies of blurb (4).
Dependency	Optional
pyfakefs	true
pytest	true
pytest-cov	true
time-machine	true

Package profile

blurb

Releases

Release table

PyPI Downloads

Dependencies

Details

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Dependencies

Package description