hideshow: Deep cleaning. (Bug#79934)

This is just a refactoring change, simplifying most of the code
and commentaries and removing/deprecating redundant code.

* etc/NEWS: Announce changes.
* lisp/progmodes/hideshow.el (hs-hide-hook, hs-show-hook): Use
'defcustom' instead of 'defvar'.
(hs-block-end-regexp, hs-forward-sexp-function)
(hs-adjust-block-beginning-function)
(hs-adjust-block-end-function, hs-find-block-beginning-function)
(hs-find-next-block-function)
(hs-looking-at-block-start-predicate)
(hs-inside-comment-predicate): Update docstring.
(hs-discard-overlays): Simplify.
(hs-life-goes-on): Update docstring.
(hs-hideable-region-p): Revert previous changes.
(hs-overlay-at): Simplify.
(hs-make-overlay): Fix performance.
(hs-block-positions): Rework.
(hs--add-indicators): Fix performance.
(hs-isearch-show-temporary): Simplify.
(hs-looking-at-block-start-p): Rename ...
(hs-looking-at-block-start-p--default): ... to this.
(hs-forward-sexp, hs-hide-comment-region): Mark as obsolete.
(hs-hide-block-at-point): Rework.
(hs-get-first-block): Rename ...
(hs-get-first-block-on-line): ... to this.
(hs-inside-comment-p--default): Rework.
(hs-find-block-beginning): Rename ...
(hs-find-block-beg-fn--default): ... to this.
(hs-find-next-block): Rename ...
(hs-find-next-block-fn--default): ... to this.
(hs-hide-level-recursive): Rework.
(hs-find-block-beginning-match): Remove function.
(hs-already-hidden-p): Simplify.
(hs-c-like-adjust-block-beginning): Mark as obsolete.
(hs-hide-all, hs-show-all, hs-hide-block, hs-show-block)
(hs-hide-level, hs-hide-initial-comment-block, hs-cycle):
Simplify.
* test/lisp/progmodes/hideshow-tests.el (hideshow-hide-level-1)
(hideshow-hide-level-2):
* test/lisp/progmodes/python-tests.el
(python-hideshow-hide-levels-3, python-hideshow-hide-levels-4):
* test/lisp/progmodes/hideshow-tests.el (hideshow-hide-level-1)
(hideshow-hide-level-2):
* test/lisp/progmodes/python-tests.el
(python-hideshow-hide-levels-3, python-hideshow-hide-levels-4):
Update tests.

1 files changed, 9 insertions, 3 deletions

diff --git a/test/lisp/progmodes/python-tests.el b/test/lisp/progmodes/python-tests.el
index b9130da495d..6ddd57c9db2 100644
--- a/test/lisp/progmodes/python-tests.el
+++ b/test/lisp/progmodes/python-tests.el
@@ -7428,7 +7428,7 @@ class SomeClass:
       (or enabled (hs-minor-mode -1)))))
 
 (ert-deftest python-hideshow-hide-levels-3 ()
-  "Should hide all blocks."
+  "Should hide 2nd level blocks."
   (python-tests-with-temp-buffer
    "
 def f():
@@ -7447,19 +7447,22 @@ def g():
      (python-tests-visible-string)
      "
 def f():
+    if 0:
 
 def g():
+    pass
 "))))
 
 (ert-deftest python-hideshow-hide-levels-4 ()
-  "Should hide 2nd level block."
+  "Should hide 3nd level block."
   (python-tests-with-temp-buffer
    "
 def f():
     if 0:
         l = [i for i in range(5)
              if i < 3]
-        abc = o.match(1, 2, 3)
+        if 1:
+            abc = o.match(1, 2, 3)
 
 def g():
     pass
@@ -7472,6 +7475,9 @@ def g():
      "
 def f():
     if 0:
+        l = [i for i in range(5)
+             if i < 3]
+        if 1:
 
 def g():
     pass