[nongnu] elpa/eldoc-diffstat 8786bab235 04/10: Add support for Hg repos

[ELPA Syncer]

branch: elpa/eldoc-diffstat
commit 8786bab235c7c961c275e47043a929624dddddb5
Author: Johann Klähn <johann@jklaehn.de>
Commit: Johann Klähn <johann@jklaehn.de>

    Add support for Hg repos
---
 eldoc-diffstat.el | 85 +++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 55 insertions(+), 30 deletions(-)

diff --git a/eldoc-diffstat.el b/eldoc-diffstat.el
index ca6b599efe..0041a51aae 100644
--- a/eldoc-diffstat.el
+++ b/eldoc-diffstat.el
@@ -1,4 +1,4 @@
-;;; eldoc-diffstat.el --- Make git diffstat available via eldoc  -*- 
lexical-binding: t; -*-
+;;; eldoc-diffstat.el --- Make VCS diffstat available via eldoc  -*- 
lexical-binding: t; -*-
 
 ;; Copyright (C) 2024  Johann Klähn
 
@@ -27,39 +27,60 @@
 (require 'ansi-color)
 
 (defvar eldoc-diffstat--process nil)
-(defconst eldoc-diffstat--command
-  (list "git" "--no-pager" "show" "--color=always"
-        "--format=format:%an <%ae>, %aD:%n%s" "--stat=80"))
+(defconst eldoc-diffstat--commands
+  '((Git "git" "--no-pager" "show" "--color=always"
+         "--format=format:%an <%ae>, %aD:%n%s" "--stat=80")
+    (Hg "hg" "--pager=never" "log" "--color=always"
+        "--template" "{author}, {date|rfc822date}:\n{desc|firstline}\n"
+        "--stat" "--rev")))
 
 ;;;###autoload
 (defun eldoc-diffstat-setup ()
-  "Configure eldoc buffer-locally to display diffstat for commit at point."
+  "Configure eldoc buffer-locally to display diffstat for revision at point."
   (interactive)
+  (unless (bound-and-true-p eldoc-mode)
+    (eldoc-mode))
   (add-hook 'eldoc-documentation-functions
             #'eldoc-diffstat--docstring nil 'local))
 
 (defun eldoc-diffstat--docstring (callback &rest _ignored)
-  "Display diffstat for commit at point by calling CALLBACK.
+  "Display diffstat for revision at point by calling CALLBACK.
 Intended for `eldoc-documentation-functions'."
-  (when-let* ((commit (or (when (fboundp 'magit-commit-at-point)
-                            (magit-commit-at-point))
-                          (and (derived-mode-p 'vc-annotate-mode)
-                               (boundp 'vc-annotate-backend)
-                               (eq vc-annotate-backend 'Git)
-                               (fboundp 'vc-annotate-extract-revision-at-line)
-                               (car (vc-annotate-extract-revision-at-line)))
-                          (and (derived-mode-p 'log-view-mode)
-                               (boundp 'log-view-vc-backend)
-                               (eq log-view-vc-backend 'Git)
-                               (log-view-current-tag)))))
-    (if-let* (((processp eldoc-diffstat--process))
-              (result (process-get eldoc-diffstat--process :result))
-              ((equal commit (car result))))
-        (funcall callback (cdr result))
-      (eldoc-diffstat--docstring-1 commit callback))))
-
-(defun eldoc-diffstat--docstring-1 (commit callback &rest _ignored)
-  "Display diffstat for COMMIT by calling CALLBACK."
+  (when-let* ((info (or (when-let (((fboundp 'magit-commit-at-point))
+                                   (revision (magit-commit-at-point)))
+                          (cons 'Git revision))
+                        (and (derived-mode-p 'vc-annotate-mode)
+                             (boundp 'vc-annotate-backend)
+                             (fboundp 'vc-annotate-extract-revision-at-line)
+                             (cons vc-annotate-backend
+                                   (car 
(vc-annotate-extract-revision-at-line))))
+                        (and (derived-mode-p 'log-view-mode)
+                             (boundp 'log-view-vc-backend)
+                             (cons log-view-vc-backend
+                                   (log-view-current-tag)))))
+              (backend (car info))
+              (revision (cdr info))
+              (command (alist-get backend eldoc-diffstat--commands)))
+    (if-let ((result (eldoc--diffstat--get-cache info)))
+        (funcall callback result)
+      (eldoc-diffstat--docstring-1 (append command (list revision)) callback 
info))))
+
+(defun eldoc--diffstat--get-cache (cache-tag)
+  "Retrieve cached diffstat result for CACHE-TAG if available.
+CACHE-TAG is a cons cell of the form (BACKEND . REVISION) where BACKEND is
+a symbol representing the version control system and REVISION is a string
+identifying the specific revision.  Returns the cached result if available,
+nil otherwise."
+  (when-let* (((processp eldoc-diffstat--process))
+              (cached-result (process-get eldoc-diffstat--process 
:cached-result))
+              ((equal cache-tag (car cached-result))))
+    (cdr cached-result)))
+
+(defun eldoc-diffstat--docstring-1 (command callback cache-tag)
+  "Asynchronously compute diffstat using COMMAND and pass it to CALLBACK.
+This function sets up a new asynchronous process to compute the diffstat,
+killing any existing process.  CACHE-TAG is a unique identifier used for
+caching the result, see `eldoc-diffstat--get-cache' for details."
   ;; Clean up old process and its buffer.
   (when (processp eldoc-diffstat--process)
     (when (process-live-p eldoc-diffstat--process)
@@ -73,11 +94,10 @@ Intended for `eldoc-documentation-functions'."
     :name "eldoc-diffstat"
     :buffer (generate-new-buffer " *eldoc-diffstat*")
     :noquery t
-    :command
-    (append eldoc-diffstat--command (list commit))
+    :command command
     :sentinel
     (apply-partially #'eldoc-diffstat--sentinel callback)))
-  (process-put eldoc-diffstat--process :commit commit)
+  (process-put eldoc-diffstat--process :cache-tag cache-tag)
 
   ;; Signal that the doc string is computed asynchronously.
   t)
@@ -91,6 +111,10 @@ Intended for `eldoc-documentation-functions'."
                (put-text-property beg end 'face face))))
         (ansi-color-apply-on-region (point-min) (point-max)))
 
+      ;; Delete trailing blank lines.
+      (goto-char (point-max))
+      (delete-blank-lines)
+
       ;; Make first line bold.
       (goto-char (point-min))
       (put-text-property (point)
@@ -110,8 +134,9 @@ Intended for `eldoc-documentation-functions'."
       (forward-line)
       (reverse-region (point) (point-max))
       (let ((result (buffer-string))
-            (commit (process-get eldoc-diffstat--process :commit)))
-        (process-put eldoc-diffstat--process :result (cons commit result))
+            (cache-tag (process-get eldoc-diffstat--process :cache-tag)))
+        (process-put eldoc-diffstat--process :cached-result
+                     (cons cache-tag result))
         (funcall callback result)))))
 
 (provide 'eldoc-diffstat)