From 0aa85dd219f4be8dbf3383661fd2b42370945b87 Mon Sep 17 00:00:00 2001 From: Craig Jennings Date: Sun, 21 Jun 2026 03:19:08 -0400 Subject: test: make subr mocks variadic for native-comp, add arity meta-test Re-enabling native-comp surfaced a suite-wide fragility. When a test redefines a C primitive (or a native-compiled function), native-comp routes native callers through a trampoline that calls the mock with the primitive's maximum arity. A fixed-arity mock narrower than the primitive then throws wrong-number-of-arguments, intermittently, as the eln-cache fills. I swept every arity-narrow subr mock to append &rest _ (188 sites, preserving any named args the body uses), and added tests/test-meta-subr-mock-arity.el, which fails make test on any subr mock too narrow for the primitive's arity. The rule isn't "never mock a subr". The suite mocks message and completing-read freely. It's "a subr mock must accept the primitive's arity." Background, the three failure modes, and the research are in docs/native-comp-subr-mocking.org. --- tests/test-prog-yaml--yaml-format-buffer.el | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'tests/test-prog-yaml--yaml-format-buffer.el') diff --git a/tests/test-prog-yaml--yaml-format-buffer.el b/tests/test-prog-yaml--yaml-format-buffer.el index 28ad351f9..aae3199ce 100644 --- a/tests/test-prog-yaml--yaml-format-buffer.el +++ b/tests/test-prog-yaml--yaml-format-buffer.el @@ -14,7 +14,7 @@ (ert-deftest test-prog-yaml--yaml-format-buffer-invokes-prettier-argv () "Normal: with prettier present, the formatter calls it via argv, no shell." (let (program args) - (cl-letf (((symbol-function 'executable-find) (lambda (_p) "/usr/bin/prettier")) + (cl-letf (((symbol-function 'executable-find) (lambda (_p &rest _) "/usr/bin/prettier")) ((symbol-function 'call-process-region) (lambda (_start _end prog &rest rest) (setq program prog @@ -29,7 +29,7 @@ (ert-deftest test-prog-yaml--yaml-format-buffer-no-clobber-on-failure () "Error: a non-zero prettier exit leaves the buffer untouched and errors." - (cl-letf (((symbol-function 'executable-find) (lambda (_p) "/usr/bin/prettier")) + (cl-letf (((symbol-function 'executable-find) (lambda (_p &rest _) "/usr/bin/prettier")) ((symbol-function 'call-process-region) (lambda (_start _end _prog _delete buffer &rest _) (with-current-buffer buffer (insert "[error] bad yaml")) @@ -98,7 +98,7 @@ (ert-deftest test-prog-yaml--yaml-format-buffer-error-no-prettier () "Signals user-error when prettier is not found." - (cl-letf (((symbol-function 'executable-find) (lambda (_) nil))) + (cl-letf (((symbol-function 'executable-find) (lambda (_ &rest _) nil))) (with-temp-buffer (insert "key: value\n") (should-error (cj/yaml-format-buffer) :type 'user-error)))) -- cgit v1.2.3