bash regex to match semantic version number

Question

I have the following:

versionNumber=$(sw_vers -productVersion) # Finds version number

versionShort=${versionNumber:0:4}  # Cut string to 1 decimal place for calculation

which works when versions are like this:

10.9.2
10.9.5

but it will not match

10.10.3

as it will return only

10.1

but I want the versionShort to be set to

10.10

I am wanting to match the major version, the first dot and the minor version as above.

Answer 1

https://github.com/fsaintjacques/semver-tool https://github.com/fsaintjacques/semver-tool/blob/master/src/semver

SEMVER_REGEX="^(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)(\\-[0-9A-Za-z-]+(\\.[0-9A-Za-z-]+)*)?(\\+[0-9A-Za-z-]+(\\.[0-9A-Za-z-]+)*)?$"


function validate-version {
  local version=$1
  if [[ "$version" =~ $SEMVER_REGEX ]]; then
    # if a second argument is passed, store the result in var named by $2
    if [ "$#" -eq "2" ]; then
      local major=${BASH_REMATCH[1]}
      local minor=${BASH_REMATCH[2]}
      local patch=${BASH_REMATCH[3]}
      local prere=${BASH_REMATCH[4]}
      local build=${BASH_REMATCH[5]}
      eval "$2=(\"$major\" \"$minor\" \"$patch\" \"$prere\" \"$build\")"
    else
      echo "$version"
    fi
  else
    error "version $version does not match the semver scheme 'X.Y.Z(-PRERELEASE)(+BUILD)'. See help for more information."
  fi
}