git-ext-test

#!/bin/bash
#|
#| Tests a Git repository for various conditions and acts as a test or a filter.
#|
#| Usage:
#|
#| git-ext-test [OPTION...] [--] [TEST]
#|
#| Options:
#|   -d, --dir DIR      the directory where the test should be executed. If not
#|                      given, a whole list of directories is read from STDIN
#|   -h, --help         show this help and exit
#|   -n, --not          return 0 if the TEST returned 1
#|   -s, --silent       suppress printing the name of the directory
#|
#| Arguments:
#|   TEST               the test to apply, see the details below
#|
#| Returns:
#|   0                  if the test has been passed
#|   1                  if the test failed
#|   2                  if the test command failed
#|
#| Tests:
#|   at-branch BRANCH   tests if HEAD points to the given BRANCH
#|   has-branch GLOB... tests if the repository has a local branch that matches
#|                      the given GLOB pattern
#|   is-clean           tests if the repository is as clean as it should be after
#|                      checking out
#|
#| If no TEST is specified, the command returns 0 or 1, depending on --not.

EX_TRUE=0
EX_FALSE=1
EX_ERROR=2

DIR=
NOT=0
SILENT=0

RECURSIVE_ARGS=

SCRIPT_FILE="${BASH_SOURCE[0]}"
while [[ -n "$1" ]]; do
    case "$1" in
    -d|--dir)
        DIR="$2"
        shift 2
        ;;

    -h|--help)
        sed '/#|.*/ s/^#|[[:space:]]\?//p;d' < "$SCRIPT_FILE"
        exit $EX_ERROR
        ;;

    -n|--not)
        RECURSIVE_ARGS+=' --not'
        NOT=1
        shift
        ;;

    -s|--silent)
        RECURSIVE_ARGS+=' --silent'
        SILENT=1
        shift
        ;;

    --)
        RECURSIVE_ARGS+=' --'
        shift
        break
        ;;

    -*)
        echo "Unknown option encountered: '$1'" >&2
        exit $EX_ERROR
        ;;

    *)
        break
        ;;
    esac
done

if [[ -z "$1" ]]; then
    exit $NOT # See the equality to EX_*
fi

if [[ -z "$DIR" ]]; then
    RESULT=$EX_TRUE
    while read -r DIR; do
        "$SCRIPT_FILE" $RECURSIVE_ARGS -d "$DIR" "$@"
        EXIT=$?
        if [[ $EXIT -gt $RESULT ]]; then
            RESULT=$EXIT
        fi
    done
        exit $RESULT
else
    cd "$DIR"
fi

RESULT=$EX_FALSE
case "$1" in
    at-branch)
        BRANCH=`git rev-parse --abbrev-ref HEAD`
        if [[ $? -ne 0 ]]; then
            exit $EX_ERROR
        fi

        if [[ "$BRANCH" == "$2" ]]; then
            RESULT=$EX_TRUE
        fi
        ;;

    has-branch)
        shift
        BRANCHES=`git branch --list --format '%(refname)' "$@"`
        if [[ $? -ne 0 ]]; then
            exit $EX_ERROR
        fi

        if [[ -n "$BRANCHES" ]]; then
            RESULT=$EX_TRUE
        fi
        ;;

    is-clean)
        STATUS=`git status --porcelain`
        if [[ $? -ne 0 ]]; then
            exit $EX_ERROR
        fi

        if [[ -z "$STATUS" ]]; then
            RESULT=$EX_TRUE
        fi
        ;;

    *)
        echo "Unknown test encountered: '$1'" >&2
        exit $EX_ERROR
        ;;
esac

if [[ $RESULT -eq $EX_ERROR ]]; then
    exit $EX_ERROR
fi

if [[ $NOT -ne 0 ]]; then
    if [[ $RESULT -eq $EX_TRUE ]]; then
        exit $EX_FALSE
    else
        if [[ $SILENT -eq 0 ]]; then
            echo "$DIR"
        fi
        exit $EX_TRUE
    fi
fi

if [[ $RESULT -eq $EX_TRUE && $SILENT -eq 0 ]]; then
    echo "$DIR"
fi

exit $RESULT