From: João Távora <joaotavora@gmail.com>
Date: Wed, 27 Dec 2023 12:38:31 +0000 (-0600)
Subject: Eglot: introduce eglot-events-buffer-config
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=d9b5f618baa31e97a5d675c665c9094cf757d184;p=emacs.git

Eglot: introduce eglot-events-buffer-config

* doc/misc/eglot.texi (Eglot Variables): Reword.
(Performance): Reword.

* lisp/progmodes/eglot.el (eglot-events-buffer-size): Obsolete.
(eglot-events-buffer-config): New customization variable.
(eglot--connect): Use eglot-events-buffer-config.
---

diff --git a/doc/misc/eglot.texi b/doc/misc/eglot.texi
index c0592a6fe68..fbf0b411633 100644
--- a/doc/misc/eglot.texi
+++ b/doc/misc/eglot.texi
@@ -836,13 +836,13 @@ in the background.  The value of @code{t} means block during the whole
 waiting period.  The value of @code{nil} or @code{0} means don't block at
 all during the waiting period.
 
-@item eglot-events-buffer-size
-This determines the size of the Eglot events buffer.  @xref{Eglot
-Commands, eglot-events-buffer}, for how to display that buffer.  If
-the value is changed, for it to take effect the connection should be
-restarted using @kbd{M-x eglot-reconnect}.
+@item eglot-events-buffer-config
+This configures the size and format of the Eglot events buffer.
+@xref{Eglot Commands, eglot-events-buffer}, for how to access that
+buffer.  If the value is changed, the connection should be restarted
+using @kbd{M-x eglot-reconnect} for the new value to take effect.
 @c FIXME: Shouldn't the defcustom do this by itself using the :set
-@c attribute?
+@c attribute?  Maybe not because reconnecting is a complex task.
 @xref{Troubleshooting Eglot}, for when this could be useful.
 
 @item eglot-autoshutdown
@@ -1455,12 +1455,14 @@ indicate the problems or at least provide a hint.
 @node Performance
 @section Performance
 @cindex performance problems, with Eglot
-A common and easy-to-fix cause of performance problems is the length
-of the Eglot events buffer because it represent additional work that
-Eglot must do.  After verifying Eglot is operating correctly but
-slowly, try to customize the variable @code{eglot-events-buffer-size}
-(@pxref{Eglot Variables}) to 0.  This will disable any debug logging
-and may speed things up.
+A common and easy-to-fix cause of performance problems in Eglot
+(especially in older versions) is its events buffer, since it
+represent additional work that Eglot must do (@pxref{Eglot Commands,
+eglot-events-buffer}).  If you find Eglot is operating correctly but
+slowly, try to customize the variable
+@code{eglot-events-buffer-config} (@pxref{Eglot Variables}) and set
+its @code{:size} property to 0.  This will disable recording any
+events and may speed things up.
 
 In other situations, the cause of poor performance lies in the
 language server itself.  Servers use aggressive caching and other
diff --git a/lisp/progmodes/eglot.el b/lisp/progmodes/eglot.el
index d777e488c43..9b11a22dafb 100644
--- a/lisp/progmodes/eglot.el
+++ b/lisp/progmodes/eglot.el
@@ -138,6 +138,8 @@
                         'eglot-managed-mode-hook "1.6")
 (define-obsolete-variable-alias 'eglot-confirm-server-initiated-edits
   'eglot-confirm-server-edits "1.16")
+(make-obsolete-variable 'eglot-events-buffer-size
+  'eglot-events-buffer-config "1.16")
 (define-obsolete-function-alias 'eglot--uri-to-path 'eglot-uri-to-path "1.16")
 (define-obsolete-function-alias 'eglot--path-to-uri 'eglot-path-to-uri "1.16")
 (define-obsolete-function-alias 'eglot--range-region 'eglot-range-region "1.16")
@@ -413,17 +415,29 @@ as 0, i.e. don't block at all."
   "Don't tell server of changes before Emacs's been idle for this many seconds."
   :type 'number)
 
-(defcustom eglot-events-buffer-size 2000000
-  "Control the size of the Eglot events buffer.
-If a number, don't let the buffer grow larger than that many
-characters.  If 0, don't use an event's buffer at all.  If nil,
-let the buffer grow forever.
-
-For changes on this variable to take effect on a connection
-already started, you need to restart the connection.  That can be
-done by `eglot-reconnect'."
-  :type '(choice (const :tag "No limit" nil)
-                 (integer :tag "Number of characters")))
+(defcustom eglot-events-buffer-config
+  (list :size (or (bound-and-true-p eglot-events-buffer-size) 2000000)
+        :format 'full)
+  "Configure the Eglot events buffer.
+
+Value is a plist accepting the keys `:size', which controls the
+size in characters of the buffer (0 disables, nil means
+infinite), and `:format', which controls the shape of each log
+entry (`full' includes the original JSON, `lisp' uses
+pretty-printed Lisp).
+
+For changes on this variable to take effect, you need to restart
+the LSP connection.  That can be done by `eglot-reconnect'."
+  :type '(plist :key-type (symbol :tag "Keyword")
+                :options (((const :tag "Size" :size)
+                           (choice
+                            (const :tag "No limit" nil)
+                            (integer :tag "Number of characters")))
+                          ((const :tag "Format" :format)
+                           (choice
+                            (const :tag "Full with original JSON" full)
+                            (const :tag "Shortened" short)
+                            (const :tag "Pretty-printed lisp" lisp))))))
 
 (defcustom eglot-confirm-server-edits '((eglot-rename . nil)
                                         (t . maybe-summary))
@@ -1513,7 +1527,7 @@ This docstring appeases checkdoc, that's all."
           (apply
            #'make-instance class
            :name readable-name
-           :events-buffer-config `(:size ,eglot-events-buffer-size :format full)
+           :events-buffer-config eglot-events-buffer-config
            :notification-dispatcher (funcall spread #'eglot-handle-notification)
            :request-dispatcher (funcall spread #'eglot-handle-request)
            :on-shutdown #'eglot--on-shutdown