[elpa] externals/denote e92137a548 148/355: Use file attribute for mod time while renaming

[ELPA Syncer]

branch: externals/denote
commit e92137a548ea703d4d4a068aadc6e8e5bb24224d
Author: Protesilaos Stavrou <info@protesilaos.com>
Commit: Protesilaos Stavrou <info@protesilaos.com>

    Use file attribute for mod time while renaming
    
    This means that if you are renaming "sample.pdf" from 2000-11-31 you
    will get an identifier that reflects that date, instead of CURRENT-TIME.
    
    Note that there are other file attributes for time.  Read the doc string
    of 'file-attributes'.  If there is demand for it, we can add a user
    option, otherwise I feel 'file-attribute-modification-time' is a
    reasonable default.
    
    Thanks to Jack Baty for proposing the idea over at the mailing list:
    <https://lists.sr.ht/~protesilaos/denote/%3Cm2v8t6b45f.fsf@baty.net%3E>.
---
 README.org      | 20 +++++++++++++-------
 denote-dired.el | 16 ++++++++++++----
 2 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/README.org b/README.org
index 9859436aa1..6feb5359f4 100644
--- a/README.org
+++ b/README.org
@@ -284,25 +284,31 @@ facilitate the task of renaming them.
 
 #+findex: denote-dired-rename-file
 To this end, we provide the ~denote-dired-rename-file~ command.  It has
-a two-fold purpose: (i) to change the file name of an existing note
-while retaining its identifier and (ii) to write a Denote-style file
-name for an item that was not created by ~denote~ or related commands
-(such as an image or PDF).
+a two-fold purpose: (i) to change the name of an existing file while
+retaining its identifier and (ii) to write a Denote-compliant file name
+for an item that was not created by ~denote~ or related commands (such
+as an image or PDF).
 
 The ~denote-dired-rename-file~ command will target the file at point if
 it finds one in the current Dired buffer.  Otherwise it prompts with
 minibuffer completion for a file name.  It then uses the familiar
 prompts for a =TITLE= and =KEYWORDS= the same way the ~denote~ command
-does it ([[#h:17896c8c-d97a-4faa-abf6-31df99746ca6][Points of entry]]).  As a 
final step it asks for confirmation
+does ([[#h:17896c8c-d97a-4faa-abf6-31df99746ca6][Points of entry]]).  As a 
final step, it asks for confirmation
 before renaming the file at point, showing a message like:
 
 #+begin_example
 Rename sample.pdf to 20220612T052900--my-sample-title__testing.pdf? (y or n)
 #+end_example
 
+When operating on a file that has no identifier, such as =sample.pdf=,
+Denote reads the file properties to retrieve its last modification time.
+If the file was from a past date like 2000-11-31 it will get an
+identifier starting with =20001131= followed by the time component (per
+our file-naming scheme).
+
 The file type extension (e.g. =.pdf=) is read from the underlying file
-and is preserved in the renaming process.  Files that have no extension
-are simply left without one.
+and is preserved through the renaming process.  Files that have no
+extension are simply left without one.
 
 Renaming only occurs relative to the current directory.  Files are not
 moved between directories.
diff --git a/denote-dired.el b/denote-dired.el
index 2598ecae9b..1856e9e37c 100644
--- a/denote-dired.el
+++ b/denote-dired.el
@@ -80,11 +80,19 @@
 
 ;;;; Commands
 
+(defun denote-dired--file-attributes-time (file)
+  "Return `file-attribute-modification-time' of FILE as identifier."
+  (format-time-string
+   denote--id
+   (file-attribute-modification-time (file-attributes file))))
+
 (defun denote-dired--file-name-id (file)
-  "Return FILE identifier, else provide one."
-  (if (string-match denote--id-regexp file)
-      (substring file (match-beginning 0) (match-end 0))
-    (format-time-string denote--id)))
+  "Return FILE identifier, else generate one."
+  (cond
+   ((string-match denote--id-regexp file)
+    (substring file (match-beginning 0) (match-end 0)))
+   ((denote-dired--file-attributes-time file))
+   (t (format-time-string denote--id))))
 
 ;;;###autoload
 (defun denote-dired-rename-file (file title keywords)