Source *sh environments from fish.

bourne.fish

function set_bourne
    set --local line $argv[1]  # the line X=Y
    set --local exp $argv[2]  # 1/0: export the variable

    set --local key (echo $line | perl -pe 's/^([A-Za-z0-9_]+)=(.*)/$1/g')
    set --local dataraw (echo $line | perl -pe 's/^([A-Za-z0-9_]+)=(.*)/$2/g')
    set --local data $dataraw

    # echo "in set_bourne for $key with $exp"
    # echo "old value: $$key"
    # string join \n $$key
    # echo "dataraw: $dataraw"

    # Replace ':' with ' ' for fish arrays
    # except for those in the blacklist, FISH_BOURNE_ARRAY_BLACKLIST
    # echo "is '$key' in FISH_BOURNE_ARRAY_BLACKLIST? ($FISH_BOURNE_ARRAY_BLACKLIST)"
    if not contains $key $FISH_BOURNE_ARRAY_BLACKLIST
        # no --local here because that would scope to
        # this inner conditional block
        # set data (echo $data | tr ':' ' ')
        set data (string split ':' $data)
    end

    # Expand variables
    # set --local data (eval echo \"$data\")
    # set --local data (eval printf '\%s\n' $data)
    eval set --local data "$data"

    # echo "final: $data"
    # string join \n $data

    set --local flags 'g'
    if test $exp -eq 1
        # handle exports
        set flags $flags x
    end

    eval set "-"(string join '' $flags) $key $data

    # echo "result:"
    # string join \n $$key
end

function source_bourne
    set --local file $argv[1]
    # echo "SOURCING $file"

    if not test -e $file
        echo "error: file does not exist: $file" 1>&2
        return 1
    end

    cat $file | while read line

        switch $line
            case '#*' ''
                continue

            case 'alias *'
                eval $line

            case 'source *'
                # TODO: support arguments
                set --local data (echo $line | sed 's/^source //')
                set --local datafile (eval echo \"$data\")
                source_bourne $datafile

            case 'export *=*'
                set --local line (echo $line | sed 's/^export //')
                set_bourne $line 1
            case '*=*'
                set_bourne $line 0

            case '*'
                echo "error: unsupported: $line" # 1>&2
        end

    end
end