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-webdev-format.el | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'tests/test-prog-webdev-format.el') diff --git a/tests/test-prog-webdev-format.el b/tests/test-prog-webdev-format.el index 694f9e968..cb5da406c 100644 --- a/tests/test-prog-webdev-format.el +++ b/tests/test-prog-webdev-format.el @@ -46,7 +46,7 @@ (ert-deftest test-prog-webdev-format-buffer-runs-prettier-on-the-file () "Normal: with prettier on PATH, the argv targets `buffer-file-name'." (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) ;; rest = (DELETE BUFFER DISPLAY &rest ARGS) @@ -64,7 +64,7 @@ (ert-deftest test-prog-webdev-format-buffer-falls-back-to-file-ts () "Boundary: a buffer with no file uses the \"file.ts\" filename hint." (let (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 args (nthcdr 3 rest)) @@ -77,7 +77,7 @@ (ert-deftest test-prog-webdev-format-buffer-clamps-point-to-point-max () "Boundary: after a format that shrinks the buffer, point clamps to point-max." - (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 _) ;; Simulate prettier writing a shorter result to the output buffer. @@ -91,7 +91,7 @@ (ert-deftest test-prog-webdev-format-buffer-replaces-on-success () "Normal: a zero exit replaces the buffer with the formatter's output." - (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 "const x = 1;\n")) @@ -103,7 +103,7 @@ (ert-deftest test-prog-webdev-format-buffer-no-clobber-on-failure () "Error: a non-zero exit leaves the buffer untouched and signals an error." - (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] syntax error")) @@ -117,7 +117,7 @@ (ert-deftest test-prog-webdev-format-buffer-errors-without-prettier () "Error: prettier missing -> `user-error', nothing shells out." (let ((ran nil)) - (cl-letf (((symbol-function 'executable-find) (lambda (_p) nil)) + (cl-letf (((symbol-function 'executable-find) (lambda (_p &rest _) nil)) ((symbol-function 'call-process-region) (lambda (&rest _) (setq ran t) 0))) (with-temp-buffer -- cgit v1.2.3