[PATCH v2] Emacs: Fix notmuch-message-summary-face definition

[Teemu Likonen <tlikonen@iki.fi>]

Emacs face definition forms are either

    ((DISPLAY . PLIST)
     (DISPLAY . PLIST))

or

    ((DISPLAY PLIST)   ;For backward compatibility.
     (DISPLAY PLIST))

Commit a2388bc56e55da5d5695816818274f8a84b0ed92 (2020-08-08) follows
neither of the correct formats. It defines:

    `((((class color) (background light))
       ,@(and (>= emacs-major-version 27) '(:extend t))
       (:background "#f0f0f0"))
      (((class color) (background dark))
       ,@(and (>= emacs-major-version 27) '(:extend t))
       (:background "#303030")))

which produces:

    ((DISPLAY
      :extend t (:background "#f0f0f0"))
     (DISPLAY
      :extend t (:background "#303030")))

And that is wrong format.

This change fixes the face definition form to produce:

    ((DISPLAY
      :extend t :background "#f0f0f0")
     (DISPLAY
      :extend t :background "#303030"))

which follows the (DISPLAY . PLIST) format (see above).
---
 emacs/notmuch.el | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)


* 2020-08-16 15:51:14+02, Jonas Bernoulli wrote:

> I would recommend that you
> - switch to using the new format
> - keep the `:extend' setting on its own line
> - keep the `:extend' at the beginning of the list

The new format is the only meaningful change but OK.

> - use `and' instead of `if' because
>   - it is better to use `when' instead of `if' when
>     there is no ELSE part

I disagree with that. I think IF is more about return values and WHEN
about longer code with side effects.

>   - it is better to use `and' instead of `when` when
>     the form is about the returned value, not some
>     side-effect

To me AND is more like multiple condition for "if all the forms are
non-nil" and IF is more about return values. Obviously they are
techinally the same.

Nevertheless, I changed my IF's to AND's so there is now the smallest
possible diff in this version.


diff --git a/emacs/notmuch.el b/emacs/notmuch.el
index babddbb6..04123595 100644
--- a/emacs/notmuch.el
+++ b/emacs/notmuch.el
@@ -275,10 +275,10 @@ there will be called at other points of notmuch execution."
 (defface notmuch-message-summary-face
   `((((class color) (background light))
      ,@(and (>= emacs-major-version 27) '(:extend t))
-     (:background "#f0f0f0"))
+     :background "#f0f0f0")
     (((class color) (background dark))
      ,@(and (>= emacs-major-version 27) '(:extend t))
-     (:background "#303030")))
+     :background "#303030"))
   "Face for the single-line message summary in notmuch-show-mode."
   :group 'notmuch-show
   :group 'notmuch-faces)
-- 
2.20.1