Fix common errors in CHANGELOG.md

changelog_fixer.sh

#!/bin/zsh
sed=$(which sed)
if [ "$(uname -s)" = "Darwin" ]
then
   sed=$(which gsed)
fi

# Fix incorrect date format. For example 1-01-2021
$sed -i -E "s/^([0-9])-([0-9]{2})-([0-9]{4})/0\1-\2-\3/" CHANGELOG.md

# Fix European dates, convert to US
for i in $(cat CHANGELOG.md | grep -o -E '\d{2}-\d{2}-\d{4}')
do
    exploded=( $(echo $i | grep -Eo '\d{2,4}') )
    day="${exploded[1]}"
    month="${exploded[2]}"
    year="${exploded[3]}"

    usDate="${year}-${month}-${day}"

    $sed -i "s/${i}/${usDate}/" CHANGELOG.md
done


# Remove release from changelog
$sed -i -E  "s/## Release/##/" CHANGELOG.md

# Fix bullet list that starts with space
$sed -i -E "s/^\s-/-/g" CHANGELOG.md

# Fix h2 themes
$sed -i -E "s/^#{2}\s([a-zA-Z]+)/### \1/g" CHANGELOG.md

# Fix comments, prefix with -
$sed -i -E "2,6 ! s/^([^#-]+)/- \1/" CHANGELOG.md

# Fix incorrect bullet
# For example:
# -[DEV]
# There should be a space between the hyphen and the first word
$sed -i -E "s/^-(\S)/- \1/" CHANGELOG.md

# Also fix the incorrect releases. That look like this:
# 2.1.2 2022-01-01
# Add a hyphen between the release version and the date
$sed -i -E "s/^## ([0-9\.]+) ([0-9-]+)$/## \1 - \2/" CHANGELOG.md

# Fix releases without dates. We'll use the date 2012-12-21.
$sed -i -E "s/^## ([0,9]\.[0-9]{1,3}\.[0-9]{1,3})$/## \1 - 2012-12-21/" CHANGELOG.md
$sed -i -E "s/^## ([0-9]\.[0-9]{1,3}\.[0-9]{1,3}) ?$/## \1 - 2012-12-21/" CHANGELOG.md

# Change updated theme
$sed -i -E "s/### Updated/### Changed/" CHANGELOG.md

echo "Done! Check your CHANGELOG.md"