Merge branch 'kh/you-still-use-whatchanged-fix'

The "do you still use it?" message given by a command that is
deeply deprecated and allow us to suggest alternatives has been
updated.

* kh/you-still-use-whatchanged-fix:
  BreakingChanges: remove claim about whatchanged reports
  whatchanged: remove not-even-shorter clause
  whatchanged: hint about git-log(1) and aliasing
  you-still-use-that??: help the user help themselves
  t0014: test shadowing of aliases for a sample of builtins
  git: allow alias-shadowing deprecated builtins
  git: move seen-alias bookkeeping into handle_alias(...)
  git: add `deprecated` category to --list-cmds
  Makefile: don’t add whatchanged after it has been removed

t/t0014-alias.sh

@@ -27,6 +27,20 @@ test_expect_success 'looping aliases - internal execution' '
 	test_grep "^fatal: alias loop detected: expansion of" output
 '
 
+test_expect_success 'looping aliases - deprecated builtins' '
+	test_config alias.whatchanged pack-redundant &&
+	test_config alias.pack-redundant whatchanged &&
+	cat >expect <<-EOF &&
+	${SQ}whatchanged${SQ} is aliased to ${SQ}pack-redundant${SQ}
+	${SQ}pack-redundant${SQ} is aliased to ${SQ}whatchanged${SQ}
+	fatal: alias loop detected: expansion of ${SQ}whatchanged${SQ} does not terminate:
+	  whatchanged <==
+	  pack-redundant ==>
+	EOF
+	test_must_fail git whatchanged -h 2>actual &&
+	test_cmp expect actual
+'
+
 # This test is disabled until external loops are fixed, because would block
 # the test suite for a full minute.
 #
@@ -55,4 +69,47 @@ test_expect_success 'tracing a shell alias with arguments shows trace of prepare
 	test_cmp expect actual
 '
 
+can_alias_deprecated_builtin () {
+	cmd="$1" &&
+	# some git(1) commands will fail for `-h` (the case for
+	# git-status as of 2025-09-07)
+	test_might_fail git status -h >expect &&
+	test_file_not_empty expect &&
+	test_might_fail git -c alias."$cmd"=status "$cmd" -h >actual &&
+	test_cmp expect actual
+}
+
+test_expect_success 'can alias-shadow deprecated builtins' '
+	for cmd in $(git --list-cmds=deprecated)
+	do
+		can_alias_deprecated_builtin "$cmd" || return 1
+	done
+'
+
+test_expect_success 'can alias-shadow via two deprecated builtins' '
+	# some git(1) commands will fail... (see above)
+	test_might_fail git status -h >expect &&
+	test_file_not_empty expect &&
+	test_might_fail git -c alias.whatchanged=pack-redundant \
+		-c alias.pack-redundant=status whatchanged -h >actual &&
+	test_cmp expect actual
+'
+
+cannot_alias_regular_builtin () {
+	cmd="$1" &&
+	# some git(1) commands will fail... (see above)
+	test_might_fail git "$cmd" -h >expect &&
+	test_file_not_empty expect &&
+	test_might_fail git -c alias."$cmd"=status "$cmd" -h >actual &&
+	test_cmp expect actual
+}
+
+test_expect_success 'cannot alias-shadow a sample of regular builtins' '
+	for cmd in grep check-ref-format interpret-trailers \
+		checkout-index fast-import diagnose rev-list prune
+	do
+		cannot_alias_regular_builtin "$cmd" || return 1
+	done
+'
+
 test_done