From 86beb065db3850657155ae3267265d13d6a54953 Mon Sep 17 00:00:00 2001
From: Nathaniel Nicandro <nathanielnicandro@gmail.com>
Date: Mon, 22 Feb 2021 20:11:22 -0600
Subject: [PATCH] jupyter-kernel: Move conn-info key handling to "process"
 :extra method

---
 jupyter-kernel-process.el | 51 +++++++++++++++++++++++++++------------
 jupyter-kernel.el         | 26 +-------------------
 2 files changed, 37 insertions(+), 40 deletions(-)

diff --git a/jupyter-kernel-process.el b/jupyter-kernel-process.el
index 88d0af5..01d74ab 100644
--- a/jupyter-kernel-process.el
+++ b/jupyter-kernel-process.el
@@ -72,22 +72,43 @@ Return nil if KERNEL does not have an associated process."
   (apply #'make-jupyter-kernel-process args))
 
 (cl-defmethod jupyter-kernel :extra "process" (&rest args)
-  "Return a representation of a kernel based on an Emacs process.
-If ARGS contains a :spec key, return a `jupyter-kernel-process'
-initialized using ARGS.  If the value is the name of a
-kernelspec, the returned kernel's spec slot will be set to the
-corresponding `jupyter-kernelspec'.  The session of the returned
-kernel will be initialized with the return value of
-`jupyter-session-with-random-ports'.
+  "Return a kernel as an Emacs process.
+If ARGS contains a :spec key with a value being a
+`jupyter-kernelspec', a `jupyter-kernel-process' initialized from
+it will be returned.  The value can also be a string, in which
+case it is considered the name of a kernelspec to use.
 
-Call the next method if ARGS does not contain :spec."
-  (let ((spec (plist-get args :spec)))
-    (if (not spec) (cl-call-next-method)
-      (when (stringp spec)
-        (plist-put args :spec
-                   (or (jupyter-guess-kernelspec spec)
-                       (error "No kernelspec matching name (%s)" spec))))
-      (apply #'jupyter-kernel-process args))))
+If ARGS contains a :conn-info key, a `jupyter-kernel-process'
+with a session initialized from its value, either the name of a
+connection file to read or a connection property list itself (see
+`jupyter-read-connection'), will be returned.  The remaining ARGS
+will be used to initialize the returned kernel.
+
+Call the next method if ARGS does not contain a :spec or
+:conn-info key."
+  (if (plist-get args :server) (cl-call-next-method)
+    (let ((spec (plist-get args :spec))
+          (conn-info (plist-get args :conn-info)))
+      (cond
+       (spec
+        (when (stringp spec)
+          (plist-put args :spec
+                     (or (jupyter-guess-kernelspec spec)
+                         (error "No kernelspec matching name (%s)" spec))))
+        (cl-check-type (plist-get args :spec) jupyter-kernelspec)
+        (apply #'jupyter-kernel-process args))
+       (conn-info
+        (when (stringp conn-info)
+          (setq conn-info (jupyter-read-connection conn-info)))
+        (apply #'jupyter-kernel-process
+               :session (jupyter-session
+                         :conn-info conn-info
+                         :key (plist-get conn-info :key))
+               (cl-loop
+                for (k v) on args by #'cddr
+                unless (eq k :conn-info) collect k and collect v)))
+       (t
+        (cl-call-next-method))))))
 
 ;;; Client connection
 
diff --git a/jupyter-kernel.el b/jupyter-kernel.el
index 08e7783..fab7b48 100644
--- a/jupyter-kernel.el
+++ b/jupyter-kernel.el
@@ -62,33 +62,9 @@
 
 (cl-defgeneric jupyter-kernel (&rest args)
   "Return a kernel constructed from ARGS.
-ARGS are keyword arguments used to initialize the returned
-kernel.
-
-The default implementation will return a `jupyter-kernel' with a
-session initialized from the value of :conn-info in ARGS, either
-the name of a connection file to read or itself a connection
-property list (see `jupyter-read-connection').  A client can
-connect to the returned kernel using `jupyter-client'.
 
 This method can be extended with extra primary methods for the
-purposes of handling different forms of ARGS that do not just
-need the default behavior."
-  (let ((conn-info (plist-get args :conn-info)))
-    (cond
-     (conn-info
-      (when (stringp conn-info)
-        (setq conn-info (jupyter-read-connection conn-info)))
-      ;; TODO: A `jupyter-io' method that handles this case.
-      (apply #'make-jupyter-kernel
-             :session (jupyter-session
-                       :conn-info conn-info
-                       :key (plist-get conn-info :key))
-             (cl-loop
-              for (k v) on args by #'cddr
-              unless (eq k :conn-info) collect k and collect v)))
-     (t
-      (cl-call-next-method)))))
+purposes of handling different forms of ARGS.")
 
 ;;; Kernel management