gnu: emacs-buttercup: Scope native-comp trampoline workaround to spy-on.

* gnu/packages/patches/emacs-buttercup-1.38-native-comp-spy-on-trampoline-scope.patch: New file.
* gnu/packages/emacs-build.scm (emacs-buttercup)[source]: Add it.
* gnu/local.mk (dist_patch_DATA): Add it.

Fixes: guix/guix#6927
Change-Id: I52d48090e16ce4e56839e151632d266848ec4073

3 files changed, 96 insertions, 1 deletions

diff --git a/gnu/local.mk b/gnu/local.mk
index d208b0b9de2..52324514d50 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -1228,6 +1228,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/python-treelib-remove-python2-compat.patch	\
   %D%/packages/patches/elm-offline-package-registry.patch	\
   %D%/packages/patches/elm-reactor-static-files.patch		\
+  %D%/packages/patches/emacs-buttercup-1.38-native-comp-spy-on-trampoline-scope.patch	\
   %D%/packages/patches/emacs-deferred-fix-number-of-arguments.patch	\
   %D%/packages/patches/emacs-disable-jit-compilation.patch			\
   %D%/packages/patches/emacs-doc-toc-shell-commands.patch	\
diff --git a/gnu/packages/emacs-build.scm b/gnu/packages/emacs-build.scm
index bddca2ce7e7..a771eac4bd3 100644
--- a/gnu/packages/emacs-build.scm
+++ b/gnu/packages/emacs-build.scm
@@ -72,7 +72,9 @@ as bold, underscore or italic.")
        (file-name (git-file-name name version))
        (sha256
         (base32
-         "09n8skr5wi8bs7x81d5bi6z89dd8s1zi9a5f4r2qadaz69slncxq"))))
+         "09n8skr5wi8bs7x81d5bi6z89dd8s1zi9a5f4r2qadaz69slncxq"))
+       (patches
+        (search-patches "emacs-buttercup-1.38-native-comp-spy-on-trampoline-scope.patch"))))
     (build-system emacs-build-system)
     (arguments
      (list
diff --git a/gnu/packages/patches/emacs-buttercup-1.38-native-comp-spy-on-trampoline-scope.patch b/gnu/packages/patches/emacs-buttercup-1.38-native-comp-spy-on-trampoline-scope.patch
new file mode 100644
index 00000000000..76562c51263
--- /dev/null
+++ b/gnu/packages/patches/emacs-buttercup-1.38-native-comp-spy-on-trampoline-scope.patch
@@ -0,0 +1,92 @@
+From 8d651d7247c4e8cf07ba805712cdb09e8095dd89 Mon Sep 17 00:00:00 2001
+Message-ID: <8d651d7247c4e8cf07ba805712cdb09e8095dd89.1773006315.git.dannym@friendly-machines.com>
+From: Danny Milosavljevic <dannym@friendly-machines.com>
+Date: Sun, 8 Mar 2026 21:44:05 +0000
+Subject: [PATCH] Scope native-comp trampoline disabling to spy-on only
+See: <https://github.com/jorgenschaefer/emacs-buttercup/pull/257>
+
+buttercup-with-cleanup disabled native-comp-enable-subr-trampolines
+for the entire spec execution.  This was a workaround for Emacs
+bug#61880, where trampoline compilation fails when spy-on redefines
+primitives that the trampoline compiler itself depends on (e.g.
+file-exists-p).
+
+However, disabling trampolines globally has the side effect that fset
+overrides of C primitives become invisible to natively compiled code.
+This breaks shut-up's message override when called indirectly through
+native-compiled functions like display-message-or-buffer (from
+simple.eln), because without a trampoline, the native code calls the C
+primitive directly, bypassing the fset'd function.
+
+Move the trampoline disabling from buttercup-with-cleanup into
+buttercup--spy-on-and-call-replacement, scoping it to just the fset
+call that installs the spy.  This avoids the trampoline compilation
+issue while allowing other fset overrides (e.g. from shut-up or
+cl-letf) to work correctly with native-compiled callers.
+---
+ buttercup.el | 34 +++++++++++++++++-----------------
+ 1 file changed, 17 insertions(+), 17 deletions(-)
+
+diff --git a/buttercup.el b/buttercup.el
+index 07e003f..417786d 100644
+--- a/buttercup.el
++++ b/buttercup.el
+@@ -1293,12 +1293,23 @@ responsibility to ensure ARG is a command."
+       (error "Spies can only be created in `before-each' or `it'"))))
+ 
+ 
++(defvar native-comp-enable-subr-trampolines)
++(defvar comp-enable-subr-trampolines)
++
+ (defun buttercup--spy-on-and-call-replacement (spy fun)
+   "Replace the function in symbol SPY with a spy calling FUN."
+   (let ((orig-function (and (fboundp spy) (symbol-function spy))))
+     (when (buttercup--add-cleanup (lambda ()
+                                   (fset spy orig-function)))
+-      (fset spy (buttercup--make-spy fun)))))
++      ;; Disable subr trampoline generation around the fset call.
++      ;; Redefining certain primitives causes trampoline compilation
++      ;; to fail because the trampoline compiler itself depends on
++      ;; primitives that may have just been redefined.
++      ;; See <https://github.com/jorgenschaefer/emacs-buttercup/issues/230>
++      ;; and <https://debbugs.gnu.org/61880>.
++      (let ((native-comp-enable-subr-trampolines nil)
++            (comp-enable-subr-trampolines nil))
++        (fset spy (buttercup--make-spy fun))))))
+ 
+ (defun buttercup--make-spy (fun)
+   "Create a new spy function wrapping FUN and tracking every call to itself."
+@@ -1343,24 +1354,13 @@ responsibility to ensure ARG is a command."
+ Should always be set to a value that is not `listp', except while
+ in a `buttercup-with-cleanup' environment.")
+ 
+-(defvar native-comp-enable-subr-trampolines)
+-(defvar comp-enable-subr-trampolines)
+-
+ (defmacro buttercup-with-cleanup (&rest body)
+   "Execute BODY, cleaning spys and the rest afterwards."
+-  `(,@(if (fboundp 'with-suppressed-warnings)
+-          '(with-suppressed-warnings ((obsolete comp-enable-subr-trampolines)))
+-        '(progn))
+-     (let ((buttercup--cleanup-functions nil)
+-           ;; Redefining certain primitive's trampolines will cause problems,
+-           ;; see https://github.com/jorgenschaefer/emacs-buttercup/issues/230 and
+-           ;; https://debbugs.gnu.org/cgi/bugreport.cgi?bug=61880
+-           (comp-enable-subr-trampolines nil)
+-           (native-comp-enable-subr-trampolines nil))
+-       (unwind-protect (progn ,@body)
+-         (dolist (fun buttercup--cleanup-functions)
+-           (ignore-errors
+-             (funcall fun)))))))
++  `(let ((buttercup--cleanup-functions nil))
++     (unwind-protect (progn ,@body)
++       (dolist (fun buttercup--cleanup-functions)
++         (ignore-errors
++           (funcall fun))))))
+ 
+ (defun buttercup--add-cleanup (function)
+   "Register FUNCTION for cleanup in `buttercup-with-cleanup'."
+
+base-commit: cc5a2ab7c7f18aaaf525fac61fe59bae5ad018dd
+-- 
+2.52.0