Clean up and simplify the "Testing Org" section

README.org

@@ -3693,8 +3693,9 @@ variable
 :END:
 
 Listing [[lst:batch-org-testing]] shows the recommended way: use =make test= in a
-clean Org git repository.  Listing [[lst:setup-org-mode-test-1]] and
+clean Org git repository.  In addition, on my weird Darwin system, I do =ln -sf
-[[lst:setup-org-mode-test-2]] provide facilities for [[https://orgmode.org/worg/org-tests/index.html][Testing Org]] interactively.
+VCS/org-mode/lisp= and =ln -sf VCS/org-mode/testing= to fix the command =make
+repro=.
 
 #+caption[Batch Org testing]:
 #+caption: Batch Org testing: obligatory before mailing a patch.
@@ -3703,96 +3704,6 @@ clean Org git repository.  Listing [[lst:setup-org-mode-test-1]] and
 make test > out.txt 2>&1
 #+end_src
 
-#+caption[Testing Org facilities 1]:
-#+caption: Testing Org facilities 1: for use during development only.
-#+name: lst:setup-org-mode-test-1
-#+begin_src emacs-lisp -n :results silent
-(with-eval-after-load 'emacs
-  (defvar org-testing-dir nil)
-  (defvar org-testing-lisp-files nil)
-
-  (defun setup-org-mode-test ()
-    "Initialize an `org-mode' test."
-    (interactive)
-    (unless (and org-testing-dir org-testing-lisp-files)
-      (find-library "org.el")
-      (quit-window)
-      (setq org-testing-dir
-            (file-name-concat
-             (file-name-directory
-              (directory-file-name
-               (file-name-directory
-                (buffer-file-name (get-buffer "org.el")))))
-             (file-name-as-directory "testing")))
-      (setq org-testing-lisp-files
-            (seq-filter
-             (lambda (f)
-               (string-suffix-p ".el" f))
-             (directory-files
-              (file-name-concat org-testing-dir
-                                (file-name-as-directory "lisp"))))))
-    (unless (fboundp 'org-test-with-temp-text)
-      (find-file (file-name-concat org-testing-dir "org-test.el"))
-      (eval-buffer)
-      (quit-window))
-    (let* ((test
-            (completing-read "Org-mode test: "
-                             org-testing-lisp-files nil 'require-match)))
-      (find-file (file-name-concat
-                  org-testing-dir (file-name-as-directory "lisp") test))
-      (eval-buffer)
-      (message "Evaluated '%s'"
-               (file-name-nondirectory (buffer-file-name (get-buffer test))))
-      (quit-window))))
-#+end_src
-
-#+caption[Testing Org facilities 2]:
-#+caption: Testing Org facilities 2: for use during development only.
-#+name: lst:setup-org-mode-test-2
-#+begin_src emacs-lisp -n :results silent
-(with-eval-after-load 'emacs
-  ;; Stolen from `org-test-run-all-tests'.
-  (defun org-test-run-some-tests ()
-    "Run some defined tests.
-Load all test files first."
-    (interactive)
-    (org-test-touch-all-examples)
-    (org-test-update-id-locations)
-    (org-test-load)
-    (let (;; Catch errors in diary sexps better.
-          (calendar-debug-sexp t))
-      ;; test-org-element/normalize-contents fails (can't fix).
-      ;; test-ob-exp/noweb-on-export fails due to spacing (can't fix).
-      ;; test-ob-exp/noweb-on-export-with-exports-results due to spacing (idem).
-      ;; ob-python hangs sometimes, but seldom.
-      ;; ob-tangle/continued-code-blocks-w-noweb-ref fails.
-      (ert (rx (or "org/" "org-fold" "org-element" "org-macro" "org-src"
-                   "property-inheritance"
-                   "ob/" "ob-emacs-lisp" "ob-eshell"
-                   "ob-python" "ob-tangle")))
-      (org-test-kill-all-examples)))
-
-  (defun org-test-run-ob-tests ()
-    "Run all \"ob\" tests.
-Load all test files first."
-    (interactive)
-    (org-test-load)
-    (let (;; Catch errors in diary sexps better.
-          (calendar-debug-sexp t))
-      (ert "ob/")))
-
-  (defun org-test-run-a-test-file ()
-    "Run all tests in an Org test file (trailing `/' matters).
-Examples: `ob/' or `ob-python'."
-    (interactive)
-    (let ((text (read-string "Org test file (without leading test-): "
-                             nil nil "ob-python")))
-      (org-test-load)
-      (let (;; Catch errors in diary sexps better.
-            (calendar-debug-sexp t))
-        (ert text)))))
-#+end_src
-
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