Rewrite copyright-updating tool to make it more readable and not use temporary files

add *.in and *.txt and *.sh (the ones missed by existing version)

TODO: it rewrites "test.txt" in data/test/test2.txt into two lines of "test line 1" and "test line 2". I don't know why.

.. and test copyright update in same MR

Squashed with:
* Resolve test2.txt mistery

****
mana/plus!182

1 files changed, 15 insertions, 13 deletions

diff --git a/tools/update-copyright.sh b/tools/update-copyright.sh
index 4df05c030..3eb813b6f 100755
--- a/tools/update-copyright.sh
+++ b/tools/update-copyright.sh
@@ -2,7 +2,7 @@
 # Copyright (C) 2001-2010 Wormux Team.
 # Copyright (C) 2010 The ManaWorld Development Team.
 # Copyright (C) 2012-2016 The ManaPlus Developers.
-# Copyright (C) 2021-2023 The ManaVerse Developers.
+# Copyright (C) 2021-2025 The ManaVerse Developers.
 
 cd ..
 if [[ $1 != "" ]]; then
@@ -13,18 +13,20 @@ fi
 
 [[ ! -e src ]] && echo "This script should be ran from the top manaverse dirs ./tools/ path." && exit 2
 
-tmp_file="w$RANDOM$RANDOM$RANDOM$RANDOM"
-[[ -e $tmp_file ]] && tmp_file="w$RANDOM$RANDOM$RANDOM$RANDOM"
-
 # update the dates, creating the interval if it doesn't exist yet
-find -iname "*.cpp" -or -iname "*.h" -or -iname "*.hpp" -or -iname "*.inc" -or -iname "*.cc" | 
-  xargs sed -i "/Copyright.*The ManaVerse Developers/ s,\(20[0-9]*\) \|\(20[0-9]*\)-20[0-9]* ,\1\2-$new_year ,"
+# N.B: without the type f check, sed replaces symlinks with regular files
+find -type f -a \
+     \(     -iname "*.cpp" \
+        -or -iname "*.cc" \
+        -or -iname "*.h" \
+        -or -iname "*.hpp" \
+        -or -iname "*.in" \
+        -or -iname "*.inc" \
+        -or -iname "*.sh" \
+        -or -iname "*.txt" \
+     \) -execdir sed -i "/Copyright.*The ManaVerse Developers/ s,\(20[0-9]*\) \|\(20[0-9]*\)-20[0-9]* ,\1\2-$new_year ," {} \+
 
+printf "The next +/- counts mentioning copyright lines should match:\n"
+printf "If they do not, then try finding the offending files with grep -rl <\$bad_line>\n"
 # do a semi-automated commit check
-git diff > $tmp_file
-echo "The next +/- counts mentioning copyrights should match:"
-grep "^[-+][^-+]" $tmp_file | sort | uniq -c
-echo "If they don't, try finding the offending files with grep -rl <\$bad_line>"
-
-# Remove temp file
-[[ -e $tmp_file ]] && rm $tmp_file
+git diff | grep "^[-+][^-+]" | sort | uniq -c