find all jira tickets between 2 git tags

gistfile1.txt

#!/usr/bin/env bash

set -e

## https://confluence.atlassian.com/adminjiraserver/configuring-jira-application-options-938847824.html
## Project Key Length: Default: 10
JIRA_REGEX='[A-Z]{2,10}-[0-9]{1,7}'
JIRA_TICKET=()

# Set the tags
TAG_LATEST=$(git tag --sort=taggerdate | tail -1)
TAG_PREVIOUS=$(git tag --sort=taggerdate | tail -2 | head -n 1)

echo "TAG_LATEST: $TAG_LATEST"
echo "TAG_PREVIOUS: $TAG_PREVIOUS"

# Print the commits between the two tags
GIT_LOG=$(git log --pretty=format:%s $TAG_LATEST...$TAG_PREVIOUS)

while IFS= read -r line; do
    ## check for jira ticket regex in comment message
    if [[ "$line" =~ $JIRA_REGEX ]]; then

        ## match found
        if [[ ${BASH_REMATCH[0]} ]]; then

            ## push to array 
            JIRA_MATCH="${BASH_REMATCH[0]}"
            JIRA_TICKET+=($JIRA_MATCH)
        fi
    fi

done <<< "$GIT_LOG"

## unique JIRA_TICKET
JIRA_TICKET=($(for jt in "${JIRA_TICKET[@]}"; do echo "${jt}"; done | sort -u))

FOUND_JIRA_TICKET=${#JIRA_TICKET[@]}
echo "FOUND_JIRA_TICKET: $FOUND_JIRA_TICKET"

if [ $FOUND_JIRA_TICKET -gt 0 ]; then
    echo "Jira Tickets"
    printf '%s\n' "${JIRA_TICKET[@]}"
fi

## end
###################