[elpa] externals/compat c240ac56ad: Only advise json.c functions from Emacs 28 if they exist

[ELPA Syncer]

branch: externals/compat
commit c240ac56ad83b3800f092d53dc520df3cfd60afb
Author: Philip Kaludercic <philipk@posteo.net>
Commit: Philip Kaludercic <philipk@posteo.net>

    Only advise json.c functions from Emacs 28 if they exist
---
 compat-28.1.el | 31 +++++++++++++++++++++++++------
 1 file changed, 25 insertions(+), 6 deletions(-)

diff --git a/compat-28.1.el b/compat-28.1.el
index cf9245731e..df6c8e276b 100644
--- a/compat-28.1.el
+++ b/compat-28.1.el
@@ -152,13 +152,20 @@ If COUNT is non-nil and a natural number, the function 
will
 
 ;;;; Defined in json.c
 
+(declare-function json-serialize nil (object &rest args))
+(declare-function json-parse-string nil (string &rest args))
+
 (compat-advise json-serialize (object &rest args)
   "Handle top-level JSON values."
   :cond (condition-case err
             ;; Use `random' to prevent byte compiler from optimising
             ;; the "pure" `json-serialize' call.
             (ignore (json-serialize (if (random) 0 0)))
-          (wrong-type-argument (eq (cadr err) 'json-value-p)))
+          (wrong-type-argument (eq (cadr err) 'json-value-p))
+          ;; `json-serialize' might be disabled at compile time, so we
+          ;; have to check if an error was raised that the function
+          ;; was not defined.
+          (void-function (eq (cadr err) 'json-serialize)))
   :realname compat--json-serialize-handle-tlo
   :min-version "27"
   (if (or (listp object) (vectorp object))
@@ -171,7 +178,11 @@ If COUNT is non-nil and a natural number, the function will
             ;; Use `random' to prevent byte compiler from optimising
             ;; the "pure" `json-serialize' call.
             (ignore (json-serialize (if (random) 0 0)))
-          (wrong-type-argument (eq (cadr err) 'json-value-p)))
+          (wrong-type-argument (eq (cadr err) 'json-value-p))
+          ;; `json-serialize' might be disabled at compile time, so we
+          ;; have to check if an error was raised that the function
+          ;; was not defined.
+          (void-function (eq (cadr err) 'json-serialize)))
   :realname compat--json-insert-handle-tlo
   :min-version "27"
   (if (or (listp object) (vectorp object))
@@ -180,11 +191,15 @@ If COUNT is non-nil and a natural number, the function 
will
 
 (compat-advise json-parse-string (string &rest args)
   "Handle top-level JSON values."
-  :cond (condition-case nil
+  :cond (condition-case err
             ;; Use `random' to prevent byte compiler from optimising
             ;; the "pure" `json-serialize' call.
             (ignore (json-parse-string (if (random) "0" "0")))
-          (json-parse-error t))
+          (json-parse-error t)
+          ;; `json-parse-string' might be disabled at compile time, so
+          ;; we have to check if an error was raised that the function
+          ;; was not defined.
+          (void-function (eq (cadr err) 'json-parse-error)))
   :realname compat--json-parse-string-handle-tlo
   :min-version "27"
   (if (string-match-p "\\`[[:space:]]*[[{]" string)
@@ -196,11 +211,15 @@ If COUNT is non-nil and a natural number, the function 
will
 
 (compat-advise json-parse-buffer (&rest args)
   "Handle top-level JSON values."
-  :cond (condition-case nil
+  :cond (condition-case err
             ;; Use `random' to prevent byte compiler from optimising
             ;; the "pure" `json-serialize' call.
             (ignore (json-parse-string (if (random) "0" "0")))
-          (json-parse-error t))
+          (json-parse-error t)
+          ;; `json-parse-string' might be disabled at compile time, so
+          ;; we have to check if an error was raised that the function
+          ;; was not defined.
+          (void-function (eq (cadr err) 'json-parse-error)))
   :realname compat--json-parse-buffer-handle-tlo
   :min-version "27"
   (if (looking-at-p "[[:space:]]*[[{]")