A semi-auto merge script for command-line Subversion. Place it in the branch source tree and run it.

merge_helper.sh

#!/bin/bash

# get_src_url([url])
get_src_url()
{
    local url=$1

    if [ "$url" == "" ]; then
        local merged_path=`svn propget svn:mergeinfo | head -n 1 | cut -d':' -f1`
        local root=`svn info | sed -n '/^Repository Root: / { s/Repository Root: //g; p; }'`
        echo "$root$merged_path"
        return 0
    fi

    echo "$url"
    return 0
}

# get_src_rev_list([url])
get_src_rev_list()
{
    local src_url=$(get_src_url "$1")

    echo `svn log -ql99 $src_url | sed -n '/^r/ { s/^r\([0-9]\+\).\+$/\1/g; p; };'`
    return 0
}

# get_merge_info()
get_merge_info()
{
    echo `svn propget svn:mergeinfo | head -n 1 | cut -d':' -f2 | sed 's/,/ /g'`
    return 0
}

# is_member(value, list)
is_member()
{
    local value=$1
    local list=$2

    local e
    for e in $list; do
        if [ "$value" == "$e" ]; then
            return 0
        elif [ "`echo "$e" | grep -`" != "" ]; then
            local lower_bound=`echo "$e" | cut -d'-' -f1`
            local upper_bound=`echo "$e" | cut -d'-' -f2`
            if [ $value -ge $lower_bound -a $value -le $upper_bound ]; then
                return 0
            fi
        fi
    done
    return 1
}

# get_src_unmerged_rev_list([url])
get_src_unmerged_rev_list()
{
    local src_rev_list=$(get_src_rev_list "$1")
    local merge_info=$(get_merge_info)

    local e
    for e in $src_rev_list; do
        if is_member "$e" "$merge_info"; then
            echo -n
        else
            echo "$e"
        fi
    done
    return 0
}

# show_src_unmerged_log(url, rev_str)
show_src_unmerged_log()
{
    local src_url=$(get_src_url "$1")
    local rev_str=$2
    
    if [ "$rev_str" == "" ]; then
        echo "No changes." | less
    else
        svn log -v -c $rev_str $src_url | less
    fi
    return $?
}

# do_merge(url, rev_str)
do_merge()
{
    local src_url=$(get_src_url "$1")
    local rev_str=$2

    if [ "$rev_str" == "" ]; then
        echo "Nothing to merge."
    else
        svn merge -c $rev_str $src_url
    fi
    return $?
}

# do_sep_merge(url, rev_list)
do_sep_merge()
{
    local src_url=$(get_src_url "$1")
    local rev_list=$2

    local rev
    local m_answer
    local rev_str=""
    for rev in $rev_list; do
        svn log -vc $rev "$src_url"
        echo
        echo -n "Merge rev. $rev? (y/N) "
        read m_answer
        echo

        if [ "$m_answer" == "y" -o "$m_answer" == "Y" ]; then
            rev_str="$rev_str,$rev"
        fi
    done

    if [ "$rev_str" != "" ]; then
        rev_str=${rev_str:1}
        svn merge -c $rev_str "$src_url"
        echo
        echo "Done merging $rev_str."
        echo
    else
        echo
        echo "No revision(s) selected."
        echo
    fi
}

# ./merge_helper.sh [src url]
raw_unmerged=$(get_src_unmerged_rev_list "$1")
sorted_raw_unmerged=`echo "$raw_unmerged" | sort -g`
unmerged=`echo $sorted_raw_unmerged | sed 's/ /,/g'`
show_src_unmerged_log "$1" "$unmerged"

echo 
echo "$unmerged"
echo

if [ "$unmerged" != "" ]; then
    echo -n "Merge all? (y/n/Abort) "
    read merge_answer
    echo

    if [ "$merge_answer" == "y" -o "$merge_answer" == "Y" ]; then
        do_merge "$1" "$unmerged"
    elif [ "$merge_answer" == "n" -o "$merge_answer" == "N" ]; then
        rev_list=`echo $sorted_raw_unmerged`
        do_sep_merge "$1" "$rev_list"
    else
        exit 0
    fi
fi