Merge pull request 'only validate each commit once' (#7) from validate-each-commit-once-only into main

Reviewed-on: #7
Reviewed-by: Artur Neumann <artur@jankaritech.eu>

hooks/validate.sh

@@ -42,6 +42,7 @@ if [[ ! -d "$DIR" ]]; then DIR="$PWD"; fi
 . "$DIR/timestamping"
 
 declare -i MINVERSION=$TIMESTAMPING_VERSION
+declare -A PROCESSED_COMMIT
 
 while [[ $# -gt 0 ]]; do
   KEY="$1"
@@ -89,6 +90,10 @@ fi
 # tokens, the function will return 0 but echo a warning about the invalid token.
 validate_commit() {
   local COMMIT_HASH="$1"
+  if [[ ${PROCESSED_COMMIT[$COMMIT_HASH]} ]]; then
+    log "validate_commit for $COMMIT_HASH has already been validated"
+    return 0
+  fi
   log "validate_commit for $COMMIT_HASH"
 
   local TIMESTAMP_COMMIT_VERSION
@@ -275,6 +280,8 @@ validate_commit() {
   #assert that all extracted timestamps have been processed
   assert "[ $NUM_PROCESSED -eq $NUM_EXTRACTED ]" "All extracted token must be processed."
 
+  PROCESSED_COMMIT[$COMMIT_HASH]=1
+
   if [ $NUM_VALID -gt 0 ]; then
     if [ $NUM_INVALID -gt 0 ]; then
       echo_warning "Warning: While commit $COMMIT_HASH contains $NUM_VALID valid timestamp tokens and thus is considered proppely timestamped, it also contains $NUM_INVALID invalid timestamp tokens."