Released Modus themes 0.7.0

I just published version 0.7.0 of the Modus themes. These are my highly-accessible themes for GNU Emacs. They conform with the WCAG AAA standard for colour contrast accessibility (a minimum contrast ratio of 7:1 between the foreground and background values). You can find the packages on ELPA, MELPA, MELPA stable:

  • modus-operandi-theme (light)
  • modus-vivendi-theme (dark)

Below are the release notes copied verbatim.


Modus Operandi and Modus Vivendi version 0.7.0

By Protesilaos Stavrou <info@protesilaos.com> on 2020-03-30

This entry documents the changes since version 0.6.0 (2020-03-01).  The
present release is the largest to date containing 110 commits.

All changes conform with the primary objective of this project, which is
conformance with the WCAG AAA accessibility standard for colour
contrast.  This represents a minimum contrast ratio of 7:1 between a
given combination of foreground and background colours.

All customisation options mentioned herein are off ('nil') by default.
The project's policy is to offer such features on an "opt-in" basis.
Refer to the README or each theme's source code for the names of these
user-facing symbols.

Major refinements to existing face groups
-----------------------------------------

+ The headline feature of this release is a refined set of colours for
  visualising version-control-system differences ("diffs").  The new
  colours are less intense than before and are designed to better convey
  the meaning of the constructs they apply to.  Affected face groups are
  those of 'magit' and 'diff-mode'.  A future release will assess how
  similar packages, such as 'ediff', can benefit from this work.

+ The other major set of changes concerns the colours that apply to
  fringes (see 'fringe-mode').  A new customisation option allows for a
  distinct background for the fringes (courtesy of Anders Johansson in
  commit 80fb704).  The default uses the same colours as the main
  buffer's background.  Building on this effort, fringe indicators, such
  as those of 'flycheck' now benefit from an entirely new set of
  background+foreground colour combinations that are designed
  specifically for the fringes.

+ A new customisation option allows users to render 'org-mode' source
  blocks in a distinct background colour.  The default is to use the
  same background as the rest of the buffer.  When this option is
  enabled, the background colour for the beginning and end line of such
  blocks is extended to the end of the window (using the ':extend t'
  attribute for >= Emacs 27).  Older Emacs versions already extend to
  the end of the window.

+ The colour combination that shows the matching parentheses or
  delimiters has been reviewed.  The commit is fairly small and the
  changes are immediately noticeable only to the most discerning of
  eyes.  Still, the considerations informing the review imposed a
  rigorous method.  Rather than summarise the findings, interested
  readers are advised to refer to commit af3a327: it offers a
  comprehensive analysis on the matter.

Added support for packages (A-Z)
--------------------------------

+ auctex/tex
+ bm
+ buffer-expose
+ centaur-tabs
+ cider (tentative, feedback is much appreciated)
+ csv-mode
+ dynamic-ruler
+ ebdb
+ elfeed-score
+ flyspell-correct
+ fold-this
+ freeze-it
+ frog-menu
+ git-walktree
+ helm-switch-shell
+ highlight-defined
+ highlight-escape-sequences (hes-mode)
+ highlight-numbers
+ highlight-thing
+ hl-todo
+ ioccur
+ julia
+ kaocha-runner
+ markup-faces (adoc-mode)
+ multiple-cursors
+ num3-mode
+ org-roam
+ org-superstar
+ org-treescope
+ outline-minor-mode
+ paradox
+ rainbow-identifiers
+ rg
+ ripgrep
+ sallet (tentative, feedback is much appreciated)
+ selectrum
+ sesman
+ side-notes
+ skewer-mode
+ stripes
+ symbol-overlay
+ syslog-mode
+ vc-annotate (C-x v g)
+ volatile-highlights
+ web-mode
+ yaml-mode

Note about VC-annotate
----------------------

Quoting from the relevant note in the project's README:

    Due to the unique way `vc-annotate' (`C-x v g') applies colours,
    support for its background mode (`vc-annotate-background-mode') is
    disabled at the theme level.

    Normally, such a drastic measure should not belong in a theme:
    assuming the user's preferences is bad practice.  However, it has
    been deemed necessary in the interest of preserving colour contrast
    accessibility while still supporting a useful built-in tool.

    If there actually is a way to avoid such a course of action, without
    prejudice to the accessibility standard of this project, then please
    report as much (or contribute as per the information in the
    Contributing section).


Overview of refinements to already supported packages
-----------------------------------------------------

In this section the notion of "dedicated colours" pertains to colour
values that are reserved for special faces.  They are never used for
syntax highlighting or other common scenaria.

+ Define new background colours for fringe indicators (as noted in the
  first section).  Apply them to 'bm', 'diff-hl', 'git-gutter',
  'flycheck' fringe indicators.  All such indicators are now made more
  visible and work better with the new customisation option for
  rendering the fringes in a distinct background.

+ Define dedicated colours for tab-like interfaces.  Currently these
  apply only to 'centaur-tabs'.  The intention is to eventually
  implement them to the tab modes that ship with Emacs 27, as well as
  any other package that offers such functionality.

+ Define dedicated colours for actions that "mark" items.  Use them in
  'dired', 'proced', 'gnus'. An accented background is combined with an
  accented foreground.  The intention is to make the underlying
  construct distinct even under circumstances where the mark's
  background changes, such as when it intersects with 'hl-line-mode' or
  'stripes': the accented foreground will still be recognisable as a
  colour that differs from the main foreground.  The use of a bold font
  weight further reinforces the intended action.

+ Refine 'dired' faces to account for the new "mark" styles.
  Directories are no longer rendered in a bold weight.

+ Tweak the colours used in the built-in 'diary' and 'calendar' for
  better usability.

+ Tweak 'deadgrep' colours for consistency with packages that offer
  similar functionality.

+ Tweak 'compilation-line-number' in the interest of consistency with
  similar interfaces.

+ Use a more appropriate colour for 'trailing-whitespace'.  It now is a
  colour value that was designed specifically as a background.

+ Expand 'fountain-mode' support by covering its new heading faces.  The
  headings will be presented in larger font sizes, or using proportional
  fonts, should the user enable the relevant theme customisation options
  (see README or source code).

+ Remove bold weight from matching parentheses in 'show-paren-mode' and
  'smartparens'.  The temporarily applied bold weight can cause
  misalignments while using certain fonts.  Also apply the new colours
  for matching delimiters, as documented in the first section.

+ Refine 'outline-mode' colours to be consistent with those of Org's
  headings.

+ Several usability and colour refinements for 'helm' and related
  packages in that milieu.

+ Remove box property from emphasis markers in the mode line.  It
  created inconsistencies with other faces.

+ Refine the colours used in Magit logs, `change-log', `log-view'.  They
  are meant to be more distinct from their context, without drawing too
  much attention to themselves.

+ Minor internal fixes for indentation and the like.

Miscellaneous changes and concluding remarks
--------------------------------------------

+ Add section in the README which documents a legal requirement for all
  potential non-trivial code contributions: the need to assign copyright
  to the Free Software Foundation.  The Modus Themes are now distributed
  via the official GNU ELPA repository and copyright over them is
  assigned to the FSF.

+ Add CHANGELOG file which consolidates all tagged release notes such as
  this one.

+ Add new screen shots to the relevant Wiki page, together with detailed
  descriptions on what is being demonstrated:
  https://gitlab.com/protesilaos/modus-themes/-/wikis/Screenshots

Special thanks to Manuel Uberti for reporting several issues and
offering feedback where appropriate.  I was able to add support for lots
of new packages.  While a few among the already supported face groups
underwent tweaks and refinements.  The 'helm' ecosystem benefited the
most.

Thanks to Anders Johansson for the patch that introduced the
fringes-related customisation option.  It inspired me to reconsider the
use of this particular area of the interface, which eventually led to
the barrage of commits that refashioned the fringe indicators.  A major
win overall.

Thanks to Jonathan Otsuka for fixing an error of mine on the naming of
some symbols.  My apologies for missing it: I will be more careful from
now on.

Note: both patches were small, requiring no copyright assignment.
Larger contributions are always welcome, though make sure you read the
section in the README with regard to assigning copyright to the Free
Software Foundation.

For more information, check the git repository of the modus-themes.