Cleanups: Use [[ instead of [.

76 files changed, 226 insertions, 237 deletions

diff --git a/bash_completion b/bash_completion
index cb4f0bfd..1782bc6d 100644
--- a/bash_completion
+++ b/bash_completion
@@ -265,7 +265,7 @@ __reassemble_comp_words_by_ref()
                 ref="$2[$j]"
                 eval $2[$j]=\${!ref}\${COMP_WORDS[i]}
                 # Indicate new cword
-                [ $i = $COMP_CWORD ] && eval $3=$j
+                [[ $i == $COMP_CWORD ]] && eval $3=$j
                 # Remove optional whitespace + word separator from line copy
                 line=${line#*"${COMP_WORDS[$i]}"}
                 # Start new word if word separator in original line is
@@ -480,7 +480,7 @@ _get_cword()
 #
 _get_pword() 
 {
-    if [ $COMP_CWORD -ge 1 ]; then
+    if [[ $COMP_CWORD -ge 1 ]]; then
         _get_cword "${@:-}" 1
     fi
 }
@@ -509,7 +509,7 @@ __ltrim_colon_completions()
         # Remove colon-word prefix from COMPREPLY items
         local colon_word=${1%${1##*:}}
         local i=${#COMPREPLY[*]}
-        while [ $((--i)) -ge 0 ]; do
+        while [[ $((--i)) -ge 0 ]]; do
             COMPREPLY[$i]=${COMPREPLY[$i]#"$colon_word"}
         done
     fi
@@ -589,7 +589,7 @@ _filedir()
         -n "$1" && "$1" != -d && ${#toks[@]} -lt 1 ]] && \
         toks+=( $( compgen -f -- $quoted ) )
 
-    [ ${#toks[@]} -ne 0 ] && compopt -o filenames 2>/dev/null
+    [[ ${#toks[@]} -ne 0 ]] && compopt -o filenames 2>/dev/null
 
     COMPREPLY+=( "${toks[@]}" )
 } # _filedir()
@@ -824,16 +824,16 @@ _mac_addresses()
 #
 _configured_interfaces()
 {
-    if [ -f /etc/debian_version ]; then
+    if [[ -f /etc/debian_version ]]; then
         # Debian system
         COMPREPLY=( $( compgen -W "$( sed -ne 's|^iface \([^ ]\{1,\}\).*$|\1|p'\
             /etc/network/interfaces )" -- "$cur" ) )
-    elif [ -f /etc/SuSE-release ]; then
+    elif [[ -f /etc/SuSE-release ]]; then
         # SuSE system
         COMPREPLY=( $( compgen -W "$( printf '%s\n' \
             /etc/sysconfig/network/ifcfg-* | \
             sed -ne 's|.*ifcfg-\(.*\)|\1|p' )" -- "$cur" ) )
-    elif [ -f /etc/pld-release ]; then
+    elif [[ -f /etc/pld-release ]]; then
         # PLD Linux
         COMPREPLY=( $( compgen -W "$( command ls -B \
             /etc/sysconfig/interfaces | \
@@ -872,9 +872,9 @@ _available_interfaces()
 {
     local cmd
 
-    if [ "${1:-}" = -w ]; then
+    if [[ ${1:-} == -w ]]; then
         cmd="iwconfig"
-    elif [ "${1:-}" = -a ]; then
+    elif [[ ${1:-} == -a ]]; then
         cmd="ifconfig"
     else
         cmd="ifconfig -a"
@@ -905,7 +905,7 @@ _tilde()
         # Try generate ~username completions
         COMPREPLY=( $( compgen -P '~' -u "${1#\~}" ) )
         result=${#COMPREPLY[@]}
-        [ $result -gt 0 ] && compopt -o filenames 2>/dev/null
+        [[ $result -gt 0 ]] && compopt -o filenames 2>/dev/null
     fi
     return $result
 }
@@ -970,7 +970,7 @@ _expand()
     elif [[ "$cur" == \~* ]]; then
         cur=${cur#\~}
         COMPREPLY=( $( compgen -P '~' -u "$cur" ) )
-        [ ${#COMPREPLY[@]} -eq 1 ] && eval COMPREPLY[0]=${COMPREPLY[0]}
+        [[ ${#COMPREPLY[@]} -eq 1 ]] && eval COMPREPLY[0]=${COMPREPLY[0]}
         return ${#COMPREPLY[@]}
     fi
 }
@@ -1095,7 +1095,7 @@ _service()
     _init_completion || return
 
     # don't complete past 2nd token
-    [ $cword -gt 2 ] && return 0
+    [[ $cword -gt 2 ]] && return 0
 
     if [[ $cword -eq 1 && $prev == ?(*/)service ]]; then
         _services
@@ -1112,7 +1112,7 @@ complete -F _service service
 _sysvdirs
 for svcdir in ${sysvdirs[@]}; do
     for svc in $svcdir/!($_backup_glob); do
-        [ -x "$svc" ] && complete -F _service $svc
+        [[ -x $svc ]] && complete -F _service $svc
     done
 done
 unset svc svcdir sysvdirs
@@ -1228,7 +1228,7 @@ _fstypes()
 {
     local fss
 
-    if [ -e /proc/filesystems ] ; then
+    if [[ -e /proc/filesystems ]]; then
         # Linux
         fss="$( cut -d$'\t' -f2 /proc/filesystems )
              $( awk '! /\*/ { print $NF }' /etc/filesystems 2>/dev/null )"
@@ -1238,11 +1238,10 @@ _fstypes()
              $( awk '/^[ \t]*[^#]/ { print $3 }' /etc/mnttab 2>/dev/null )
              $( awk '/^[ \t]*[^#]/ { print $4 }' /etc/vfstab 2>/dev/null )
              $( awk '{ print $1 }' /etc/dfs/fstypes 2>/dev/null )
-             $( [ -d /etc/fs ] && command ls /etc/fs )"
+             $( [[ -d /etc/fs ]] && command ls /etc/fs )"
     fi
 
-    [ -n "$fss" ] && \
-        COMPREPLY+=( $( compgen -W "$fss" -- "$cur" ) )
+    [[ -n $fss ]] && COMPREPLY+=( $( compgen -W "$fss" -- "$cur" ) )
 }
 
 # Get real command.
@@ -1396,26 +1395,25 @@ _known_hosts_real()
             p) prefix=$OPTARG ;;
         esac
     done
-    [ $# -lt $OPTIND ] && echo "error: $FUNCNAME: missing mandatory argument CWORD"
+    [[ $# -lt $OPTIND ]] && echo "error: $FUNCNAME: missing mandatory argument CWORD"
     cur=${!OPTIND}; let "OPTIND += 1"
-    [ $# -ge $OPTIND ] && echo "error: $FUNCNAME("$@"): unprocessed arguments:"\
-    $(while [ $# -ge $OPTIND ]; do printf '%s\n' ${!OPTIND}; shift; done)
+    [[ $# -ge $OPTIND ]] && echo "error: $FUNCNAME("$@"): unprocessed arguments:"\
+    $(while [[ $# -ge $OPTIND ]]; do printf '%s\n' ${!OPTIND}; shift; done)
 
     [[ $cur == *@* ]] && user=${cur%@*}@ && cur=${cur#*@}
     kh=()
 
     # ssh config files
-    if [ -n "$configfile" ]; then
-        [ -r "$configfile" ] &&
-        config+=( "$configfile" )
+    if [[ -n $configfile ]]; then
+        [[ -r $configfile ]] && config+=( "$configfile" )
     else
         for i in /etc/ssh/ssh_config ~/.ssh/config ~/.ssh2/config; do
-            [ -r "$i" ] && config+=( "$i" )
+            [[ -r $i ]] && config+=( "$i" )
         done
     fi
 
     # Known hosts files from configs
-    if [ ${#config[@]} -gt 0 ]; then
+    if [[ ${#config[@]} -gt 0 ]]; then
         local OIFS=$IFS IFS=$'\n'
         local -a tmpkh
         # expand paths (if present) to global and user known hosts files
@@ -1428,20 +1426,20 @@ _known_hosts_real()
             i=${i//\"}
             # Eval/expand possible `~' or `~user'
             __expand_tilde_by_ref i
-            [ -r "$i" ] && kh+=( "$i" )
+            [[ -r $i ]] && kh+=( "$i" )
         done
         IFS=$OIFS
     fi
 
-    if [ -z "$configfile" ]; then
+    if [[ -z $configfile ]]; then
         # Global and user known_hosts files
         for i in /etc/ssh/ssh_known_hosts /etc/ssh/ssh_known_hosts2 \
             /etc/known_hosts /etc/known_hosts2 ~/.ssh/known_hosts \
             ~/.ssh/known_hosts2; do
-            [ -r "$i" ] && kh+=( "$i" )
+            [[ -r $i ]] && kh+=( "$i" )
         done
         for i in /etc/ssh2/knownhosts ~/.ssh2/hostkeys; do
-            [ -d "$i" ] && khd+=( "$i"/*pub )
+            [[ -d $i ]] && khd+=( "$i"/*pub )
         done
     fi
 
@@ -1459,14 +1457,14 @@ _known_hosts_real()
             # Digits followed by no dot or colon - search for digits followed
             # by a dot or a colon
             awkcur="^$awkcur.*[.:]"
-        elif [ -z "$awkcur" ]; then
+        elif [[ -z $awkcur ]]; then
             # A blank - search for a dot, a colon, or an alpha character
             awkcur="[a-z.:]"
         else
             awkcur="^$awkcur"
         fi
 
-        if [ ${#kh[@]} -gt 0 ]; then
+        if [[ ${#kh[@]} -gt 0 ]]; then
             # FS needs to look for a comma separated list
             COMPREPLY+=( $( awk 'BEGIN {FS=","}
             /^\s*[^|\#]/ {
@@ -1477,7 +1475,7 @@ _known_hosts_real()
             if ($i !~ /[*?]/ && $i ~ /'"$awkcur"'/) {print $i} \
             }}' "${kh[@]}" 2>/dev/null ) )
         fi
-        if [ ${#khd[@]} -gt 0 ]; then
+        if [[ ${#khd[@]} -gt 0 ]]; then
             # Needs to look for files called
             # .../.ssh2/key_22_<hostname>.pub
             # dont fork any processes, because in a cluster environment,
@@ -1519,7 +1517,7 @@ _known_hosts_real()
 
     # Add results of normal hostname completion, unless
     # `COMP_KNOWN_HOSTS_WITH_HOSTFILE' is set to an empty value.
-    if [ -n "${COMP_KNOWN_HOSTS_WITH_HOSTFILE-1}" ]; then
+    if [[ -n ${COMP_KNOWN_HOSTS_WITH_HOSTFILE-1} ]]; then
         COMPREPLY+=(
             $( compgen -A hostname -P "$prefix$user" -S "$suffix" -- "$cur" ) )
     fi
@@ -1661,7 +1659,7 @@ _command_offset()
         fi
 
         if [[ -n $cspec ]]; then
-            if [ "${cspec#* -F }" != "$cspec" ]; then
+            if [[ ${cspec#* -F } != $cspec ]]; then
                 # complete -F <function>
 
                 # get function name
@@ -1679,7 +1677,7 @@ _command_offset()
                 while true; do
                     # FIXME: should we take "+o opt" into account?
                     t=${cspec#*-o }
-                    if [ "$t" == "$cspec" ]; then
+                    if [[ $t == $cspec ]]; then
                         break
                     fi
                     opt=${t%% *}
@@ -1691,7 +1689,7 @@ _command_offset()
                 cspec=${cspec%%$compcmd}
                 COMPREPLY=( $( eval compgen "$cspec" -- "$cur" ) )
             fi
-        elif [ ${#COMPREPLY[@]} -eq 0 ]; then
+        elif [[ ${#COMPREPLY[@]} -eq 0 ]]; then
             _minimal
         fi
     fi
@@ -1800,12 +1798,12 @@ _filedir_xspec()
     toks+=( $(
         eval compgen -f -X "!$xspec" -- "\$(quote_readline "\$cur")" | {
         while read -r tmp; do
-            [ -n $tmp ] && printf '%s\n' $tmp
+            [[ -n $tmp ]] && printf '%s\n' $tmp
         done
         }
         ))
 
-    [ ${#toks[@]} -ne 0 ] && compopt -o filenames
+    [[ ${#toks[@]} -ne 0 ]] && compopt -o filenames
     COMPREPLY=( "${toks[@]}" )
 }
 
diff --git a/completions/_mock b/completions/_mock
index cb7d6571..020b39b4 100644
--- a/completions/_mock
+++ b/completions/_mock
@@ -12,7 +12,7 @@ _mock()
     local cfgdir=/etc/mock count=0 i
 
     for i in "${words[@]}" ; do
-        [ $count -eq $cword ] && break
+        [[ $count -eq $cword ]] && break
         if [[ "$i" == --configdir ]] ; then
             cfgdir="${words[((count+1))]}"
         elif [[ "$i" == --configdir=* ]] ; then
diff --git a/completions/_modules b/completions/_modules
index 6f337a90..b5a1d94a 100644
--- a/completions/_modules
+++ b/completions/_modules
@@ -49,7 +49,7 @@ _module ()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ] ; then
+    if [[ $cword -eq 1 ]]; then
         # First parameter on line -- we expect it to be a mode selection
 
         local options
@@ -58,7 +58,7 @@ _module ()
 
         COMPREPLY=( $(compgen -W "$options" -- "$cur") )
 
-    elif [ $cword -eq 2 ] ; then
+    elif [[ $cword -eq 2 ]]; then
         case $prev in
             add|display|help|load|show|whatis)
                 COMPREPLY=( $(_module_avail "$cur") )
@@ -70,7 +70,7 @@ _module ()
                 COMPREPLY=( $(_module_path "$cur") )
                 ;;
         esac
-    elif [ $cword -eq 3 ] ; then
+    elif [[ $cword -eq 3 ]]; then
         case ${words[1]} in
             swap|switch)
                 COMPREPLY=( $(_module_avail "$cur") )
diff --git a/completions/_yum b/completions/_yum
index c2d37948..9860c540 100644
--- a/completions/_yum
+++ b/completions/_yum
@@ -45,7 +45,7 @@ _yum()
         fi
     done
 
-    if [ -n "$special" ]; then
+    if [[ -n $special ]]; then
         # TODO: install|update|upgrade should not match *src.rpm
         if [[ "$cur" == @(*/|[.~])* && \
             "$special" == @(deplist|install|update|upgrade) ]]; then
diff --git a/completions/ant b/completions/ant
index 96ef8172..dd3606dc 100644
--- a/completions/ant
+++ b/completions/ant
@@ -45,7 +45,7 @@ _ant()
                 break
             fi
         done
-        [ ! -f $buildfile ] && return 0
+        [[ ! -f $buildfile ]] && return 0
 
         # parse buildfile for targets
         local line targets
diff --git a/completions/apt-build b/completions/apt-build
index aa78b230..8e593131 100644
--- a/completions/apt-build
+++ b/completions/apt-build
@@ -12,7 +12,7 @@ _apt_build()
         fi
     done
 
-    if [ -n "$special" ]; then
+    if [[ -n $special ]]; then
         case $special in
             install|source|info)
                 COMPREPLY=( $( apt-cache pkgnames "$cur" 2> /dev/null ) )
diff --git a/completions/apt-cache b/completions/apt-cache
index 00b41478..3e2ca0db 100644
--- a/completions/apt-cache
+++ b/completions/apt-cache
@@ -6,7 +6,7 @@ _apt_cache()
     _init_completion || return
 
     local special i
-    if [ "$cur" != show ]; then
+    if [[ $cur != show ]]; then
         for (( i=0; i < ${#words[@]}-1; i++ )); do
             if [[ ${words[i]} == @(add|depends|dotty|madison|policy|rdepends|show?(pkg|src|)) ]]; then
                 special=${words[i]}
@@ -15,7 +15,7 @@ _apt_cache()
     fi
 
 
-    if [ -n "$special" ]; then
+    if [[ -n $special ]]; then
         case $special in
         add)
             _filedir
diff --git a/completions/apt-get b/completions/apt-get
index 447305a4..a6c902e1 100644
--- a/completions/apt-get
+++ b/completions/apt-get
@@ -12,10 +12,10 @@ _apt_get()
         fi
     done
 
-    if [ -n "$special" ]; then
+    if [[ -n $special ]]; then
         case $special in
             remove|autoremove|purge)
-                if [ -f /etc/debian_version ]; then
+                if [[ -f /etc/debian_version ]]; then
                     # Debian system
                     COMPREPLY=( $( \
                         _xfunc dpkg _comp_dpkg_installed_packages $cur ) )
diff --git a/completions/avctrl b/completions/avctrl
index eb321a07..bac38cd6 100644
--- a/completions/avctrl
+++ b/completions/avctrl
@@ -10,7 +10,7 @@ _avctrl()
     else
         local args
         _count_args
-        if [ $args -eq 1 ]; then
+        if [[ $args -eq 1 ]]; then
             COMPREPLY=( $( compgen -W 'discover switch' -- "$cur" ) )
         fi
     fi
diff --git a/completions/cardctl b/completions/cardctl
index 0532d6ef..90837269 100644
--- a/completions/cardctl
+++ b/completions/cardctl
@@ -5,7 +5,7 @@ _cardctl()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W 'status config ident suspend \
             resume reset eject insert scheme' -- "$cur" ) )
     fi
diff --git a/completions/cfrun b/completions/cfrun
index 288bcf43..0be44132 100644
--- a/completions/cfrun
+++ b/completions/cfrun
@@ -31,7 +31,7 @@ _cfrun()
                         break
                     fi
                 done
-                [ ! -f $hostfile ] && return 0
+                [[ ! -f $hostfile ]] && return 0
 
                 COMPREPLY=( $(compgen -W  "$( command grep -v \
                     -E '(=|^$|^#)' $hostfile )" -- "$cur" ) )
diff --git a/completions/cksfv b/completions/cksfv
index d21bcf39..eabe3730 100644
--- a/completions/cksfv
+++ b/completions/cksfv
@@ -5,7 +5,7 @@ _cksfv()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W '$( _parse_help "$1" )' -- "$cur" ) )
         return 0
     fi
diff --git a/completions/configure b/completions/configure
index 8e28d451..2337c497 100644
--- a/completions/configure
+++ b/completions/configure
@@ -26,7 +26,7 @@ _configure()
     # --option=SETTING will include 'SETTING' as a contextual hint
     [[ "$cur" != -* ]] && return 0
 
-    if [ -n "$COMP_CONFIGURE_HINTS" ]; then
+    if [[ -n $COMP_CONFIGURE_HINTS ]]; then
         COMPREPLY=( $( compgen -W "$( $1 --help 2>&1 | \
             awk '/^  --[A-Za-z]/ { print $1; \
             if ($2 ~ /--[A-Za-z]/) print $2 }' | sed -e 's/[[,].*//g' )" \
diff --git a/completions/cpio b/completions/cpio
index ebbe5c57..45824007 100644
--- a/completions/cpio
+++ b/completions/cpio
@@ -33,7 +33,7 @@ _cpio()
 
     $split && return 0
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W '-o --create -i --extract -p --pass-through \
                                    -? --help --license --usage --version' -- "$cur" ) )
     else
diff --git a/completions/cryptsetup b/completions/cryptsetup
index 2bbdc952..fb390214 100644
--- a/completions/cryptsetup
+++ b/completions/cryptsetup
@@ -28,7 +28,7 @@ _cryptsetup()
 
     local arg
     _get_first_arg
-    if [ -z $arg ]; then
+    if [[ -z $arg ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '$( _parse_help "$1" )' -- "$cur" ) )
             [[ $COMPREPLY == *= ]] && compopt -o nospace
diff --git a/completions/cvs b/completions/cvs
index bafe1901..4613742a 100644
--- a/completions/cvs
+++ b/completions/cvs
@@ -13,7 +13,7 @@ _cvs_entries()
 
 _cvs_modules()
 {
-    if [ -n "$prefix" ]; then
+    if [[ -n $prefix ]]; then
         COMPREPLY=( $( command ls -d ${cvsroot}/${prefix}/!(CVSROOT) ) )
     else
         COMPREPLY=( $( command ls -d ${cvsroot}/!(CVSROOT) ) )
@@ -39,9 +39,8 @@ _cvs_roots()
 {
     local -a cvsroots
     cvsroots=( $CVSROOT )
-    [ -r ~/.cvspass ] && \
-        cvsroots+=( $( awk '{ print $2 }' ~/.cvspass ) )
-    [ -r CVS/Root ] && mapfile -tO ${#cvsroots[@]} cvsroots < CVS/Root
+    [[ -r ~/.cvspass ]] && cvsroots+=( $( awk '{ print $2 }' ~/.cvspass ) )
+    [[ -r CVS/Root ]] && mapfile -tO ${#cvsroots[@]} cvsroots < CVS/Root
     COMPREPLY=( $( compgen -W '${cvsroots[@]}' -- "$cur" ) )
     __ltrim_colon_completions "$cur"
 }
@@ -56,12 +55,12 @@ _cvs()
 
     count=0
     for i in "${words[@]}"; do
-        [ $count -eq $cword ] && break
+        [[ $count -eq $cword ]] && break
         # Last parameter was the CVSROOT, now go back to mode selection
         if [[ "${words[((count))]}" == "$cvsroot" && "$mode" == cvsroot ]]; then
             mode=""
         fi
-        if [ -z "$mode" ]; then
+        if [[ -z $mode ]]; then
             case $i in
                 -H|--help)
                     COMPREPLY=( $( compgen -W "$( _cvs_commands )" -- "$cur" ) )
@@ -152,7 +151,7 @@ _cvs()
 
             if [[ "$cur" != -* ]]; then
                 _cvs_entries
-                [ -z "$cur" ] && files=( !(CVS) ) || \
+                [[ -z $cur ]] && files=( !(CVS) ) || \
                     files=( $( command ls -d ${cur}* 2>/dev/null ) )
                 local f
                 for i in ${!files[@]}; do
@@ -221,7 +220,7 @@ _cvs()
             esac
 
             if [[ "$cur" != -* ]]; then
-                [ -z "$cvsroot" ] && cvsroot=$CVSROOT
+                [[ -z $cvsroot ]] && cvsroot=$CVSROOT
                 COMPREPLY=( $( cvs -d "$cvsroot" co -c 2> /dev/null | \
                     awk '{print $1}' ) )
                 COMPREPLY=( $( compgen -W '${COMPREPLY[@]}' -- "$cur" ) )
@@ -244,7 +243,7 @@ _cvs()
                 # if $COMP_CVS_REMOTE is not null, 'cvs commit' will
                 # complete on remotely checked-out files (requires
                 # passwordless access to the remote repository
-                if [ -n "${COMP_CVS_REMOTE:-}" ]; then
+                if [[ -n ${COMP_CVS_REMOTE:-} ]]; then
                     # this is the least computationally intensive way found so
                     # far, but other changes (something other than
                     # changed/removed/new) may be missing
@@ -298,7 +297,7 @@ _cvs()
             esac
 
             if [[ "$cur" != -* ]]; then
-                [ -z "$cvsroot" ] && cvsroot=$CVSROOT
+                [[ -z $cvsroot ]] && cvsroot=$CVSROOT
                 COMPREPLY=( $( cvs -d "$cvsroot" co -c | awk '{print $1}' ) )
                 COMPREPLY=( $( compgen -W '${COMPREPLY[@]}' -- "$cur" ) )
             else
@@ -318,9 +317,9 @@ _cvs()
 
             if [[ "$cur" != -* ]]; then
                 # starts with same algorithm as checkout
-                [ -z "$cvsroot" ] && cvsroot=$CVSROOT
+                [[ -z $cvsroot ]] && cvsroot=$CVSROOT
                 local prefix=${cur%/*}
-                if [ -r ${cvsroot}/${prefix} ]; then
+                if [[ -r ${cvsroot}/${prefix} ]]; then
                     _cvs_modules
                     COMPREPLY=( ${COMPREPLY[@]#$cvsroot} )
                     COMPREPLY=( ${COMPREPLY[@]#\/} )
@@ -337,7 +336,7 @@ _cvs()
                 _cvs_entries
                 # find out what files are missing
                 for i in "${entries[@]}"; do
-                    [ ! -r "$i" ] && miss+=( $i )
+                    [[ ! -r $i ]] && miss+=( $i )
                 done
                 COMPREPLY=( $( compgen -W '${miss[@]:-}' -- "$cur" ) )
             else
diff --git a/completions/dict b/completions/dict
index a31816d3..3caedf76 100644
--- a/completions/dict
+++ b/completions/dict
@@ -17,17 +17,17 @@ _dict()
         case ${words[i]} in
             -h|--host)
                 host=${words[i+1]}
-                [ -n "$host" ] && host="-h $host"
+                [[ -n $host ]] && host="-h $host"
                 i=$((++i))
                 ;;
             -p|--port)
                 port=${words[i+1]}
-                [ -n "$port" ] && port="-p $port"
+                [[ -n $port ]] && port="-p $port"
                 i=$((++i))
                 ;;
             -d|--database)
                 db=${words[i+1]}
-                [ -n "$db" ] && host="-d $db"
+                [[ -n $db ]] && host="-d $db"
                 i=$((++i))
                 ;;
             *)
@@ -54,7 +54,7 @@ _dict()
     esac
 
     local dictfile=/usr/share/dict/words
-    [ -r $dictfile ] && \
+    [[ -r $dictfile ]] && \
         COMPREPLY=( $( compgen -W '$( cat $dictfile )' -- "$cur" ) )
 } &&
 complete -F _dict -o default dict rdict
diff --git a/completions/e2label b/completions/e2label
index 86008d9f..94bcc1c8 100644
--- a/completions/e2label
+++ b/completions/e2label
@@ -5,7 +5,7 @@ _e2label()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         cur=${cur:=/dev/}
         _filedir
     fi
diff --git a/completions/feh b/completions/feh
index e39b5c31..556fc13e 100644
--- a/completions/feh
+++ b/completions/feh
@@ -46,7 +46,7 @@ _feh()
         -T|--theme)
             local conf_path=~/.config/feh/themes
             local theme_name theme_opts
-            [ -r "$conf_path" ] || return
+            [[ -r $conf_path ]] || return
             while read theme_name theme_opts; do
                 if [[ "$theme_name" == '#'* || "$theme_name" == "" ]]; then
                     continue
diff --git a/completions/function b/completions/function
index 6156e63d..e12fffff 100644
--- a/completions/function
+++ b/completions/function
@@ -6,12 +6,12 @@ _function()
     _init_completion || return
 
     if [[ $1 == @(declare|typeset) ]]; then
-        if [ "$prev" = -f ]; then
+        if [[ $prev == -f ]]; then
             COMPREPLY=( $( compgen -A function -- "$cur" ) )
         elif [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '-a -f -F -i -r -x -p' -- "$cur" ) )
         fi
-    elif [ $cword -eq 1 ]; then
+    elif [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -A function -- "$cur" ) )
     else
         COMPREPLY=( "() $( type -- ${words[1]} | sed -e 1,2d )" )
diff --git a/completions/gdb b/completions/gdb
index c24407b5..125d0b15 100644
--- a/completions/gdb
+++ b/completions/gdb
@@ -5,7 +5,7 @@ _gdb()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         local IFS
         compopt -o filenames
         if [[ "$cur" == */* ]]; then
@@ -24,7 +24,7 @@ _gdb()
                 -mindepth 1 -maxdepth 1 -not -type d -executable \
                 -printf "%f\\n" 2>/dev/null)' -- "$cur" ) )
         fi
-    elif [ $cword -eq 2 ]; then
+    elif [[ $cword -eq 2 ]]; then
         COMPREPLY=( $( compgen -W "$( command ps axo comm,pid | \
             awk '{if ($1 ~ /^'"${prev##*/}"'/) print $2}' )" -- "$cur" ) )
         compopt -o filenames
diff --git a/completions/gpg b/completions/gpg
index 763086bc..f7efad3a 100644
--- a/completions/gpg
+++ b/completions/gpg
@@ -20,7 +20,7 @@ _gpg()
         -r|--recipient)
             COMPREPLY=( $( compgen -W "$( gpg --list-keys 2>/dev/null | \
                 sed -ne 's@^.*<\([^>]*\)>.*$@\1@p')" -- "$cur" ))
-            if [ -e ~/.gnupg/gpg.conf ]; then
+            if [[ -e ~/.gnupg/gpg.conf ]]; then
                 COMPREPLY+=( $( compgen -W "$( sed -ne \
                     's@^[ \t]*group[ \t][ \t]*\([^=]*\).*$@\1@p' \
                     ~/.gnupg/gpg.conf  )" -- "$cur") )
diff --git a/completions/gpg2 b/completions/gpg2
index 03d2c5b8..85e9f38c 100644
--- a/completions/gpg2
+++ b/completions/gpg2
@@ -24,7 +24,7 @@ _gpg2()
         -r|--recipient)
             COMPREPLY=( $( compgen -W "$( gpg2 --list-keys 2>/dev/null | \
                 sed -ne 's@^.*<\([^>]*\)>.*$@\1@p')" -- "$cur" ))
-            if [ -e ~/.gnupg/gpg.conf ]; then
+            if [[ -e ~/.gnupg/gpg.conf ]]; then
                 COMPREPLY+=( $( compgen -W "$( sed -ne \
                     's@^[ \t]*group[ \t][ \t]*\([^=]*\).*$@\1@p' \
                     ~/.gnupg/gpg.conf)" -- "$cur"))
diff --git a/completions/hcitool b/completions/hcitool
index 417a0c99..0a743e48 100644
--- a/completions/hcitool
+++ b/completions/hcitool
@@ -2,7 +2,7 @@
 
 _bluetooth_adresses()
 {
-    if [ -n "${COMP_BLUETOOTH_SCAN:-}" ]; then
+    if [[ -n ${COMP_BLUETOOTH_SCAN:-} ]]; then
         COMPREPLY+=( $( compgen -W "$( hcitool scan | \
             awk '/^\t/{print $1}' )" -- "$cur" ) )
     fi
@@ -51,7 +51,7 @@ _hcitool()
 
     local arg
     _get_first_arg
-    if [ -z $arg ]; then
+    if [[ -z $arg ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '$( _parse_help "$1" )' -- "$cur" ) )
         else
@@ -63,7 +63,7 @@ _hcitool()
         case $arg in
             name|info|dc|rssi|lq|afh|auth|key|clkoff|lst)
                 _count_args
-                if [ $args -eq 2 ]; then
+                if [[ $args -eq 2 ]]; then
                     _bluetooth_adresses
                 fi
                 ;;
@@ -72,14 +72,14 @@ _hcitool()
                     COMPREPLY=( $( compgen -W '--role --pkt-type' -- "$cur" ) )
                 else
                     _count_args
-                    if [ $args -eq 2 ]; then
+                    if [[ $args -eq 2 ]]; then
                         _bluetooth_adresses
                     fi
                 fi
                 ;;
             sr)
                 _count_args
-                if [ $args -eq 2 ]; then
+                if [[ $args -eq 2 ]]; then
                     _bluetooth_adresses
                 else
                     COMPREPLY=( $( compgen -W 'master slave' -- "$cur" ) )
@@ -87,7 +87,7 @@ _hcitool()
                 ;;
             cpt)
                 _count_args
-                if [ $args -eq 2 ]; then
+                if [[ $args -eq 2 ]]; then
                     _bluetooth_adresses
                 else
                     _bluetooth_packet_types
@@ -95,7 +95,7 @@ _hcitool()
                 ;;
             tpl|enc|clock)
                 _count_args
-                if [ $args -eq 2 ]; then
+                if [[ $args -eq 2 ]]; then
                     _bluetooth_adresses
                 else
                     COMPREPLY=( $( compgen -W '0 1' -- "$cur" ) )
@@ -122,7 +122,7 @@ _sdptool()
 
     local arg
     _get_first_arg
-    if [ -z $arg ]; then
+    if [[ -z $arg ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '$( _parse_help "$1" )' -- "$cur" ) )
         else
@@ -206,7 +206,7 @@ _rfcomm()
 
     local arg
     _get_first_arg
-    if [ -z $arg ]; then
+    if [[ -z $arg ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '$( _parse_help "$1" )' -- "$cur" ) )
         else
@@ -215,12 +215,12 @@ _rfcomm()
         fi
     else
         _count_args
-        if [ $args -eq 2 ]; then
+        if [[ $args -eq 2 ]]; then
             _bluetooth_devices
         else
             case $arg in
                 connect|bind)
-                    if [ $args -eq 3 ]; then
+                    if [[ $args -eq 3 ]]; then
                         _bluetooth_adresses
                     fi
                     ;;
@@ -245,7 +245,7 @@ _ciptool()
 
     local arg
     _get_first_arg
-    if [ -z $arg ]; then
+    if [[ -z $arg ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '$( _parse_help "$1" )' -- "$cur" ) )
         else
@@ -256,7 +256,7 @@ _ciptool()
         case $arg in
             connect|release|loopback)
                 _count_args
-                if [ $args -eq 2 ]; then
+                if [[ $args -eq 2 ]]; then
                     _bluetooth_adresses
                 fi
                 ;;
@@ -302,7 +302,7 @@ _hciconfig()
 
     local arg
     _get_first_arg
-    if [ -z $arg ]; then
+    if [[ -z $arg ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '--help --all' -- "$cur" ) )
         else
@@ -318,20 +318,20 @@ _hciconfig()
         case $arg in
             putkey|delkey)
                 _count_args
-                if [ $args -eq 2 ]; then
+                if [[ $args -eq 2 ]]; then
                     _bluetooth_adresses
                 fi
                 ;;
             lm)
                 _count_args
-                if [ $args -eq 2 ]; then
+                if [[ $args -eq 2 ]]; then
                     COMPREPLY=( $( compgen -W 'MASTER \
                         SLAVE NONE ACCEPT' -- "$cur" ) )
                 fi
                 ;;
             ptype)
                 _count_args
-                if [ $args -eq 2 ]; then
+                if [[ $args -eq 2 ]]; then
                     _bluetooth_packet_types
                 fi
                 ;;
diff --git a/completions/ifup b/completions/ifup
index fee87d6b..fcd34994 100644
--- a/completions/ifup
+++ b/completions/ifup
@@ -7,7 +7,7 @@ _ifupdown()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         _configured_interfaces
         COMPREPLY=( $(compgen -W '${COMPREPLY[@]}' -- "$cur") )
     fi
diff --git a/completions/info b/completions/info
index 71865809..36550449 100644
--- a/completions/info
+++ b/completions/info
@@ -45,12 +45,12 @@ _info()
 
     if [[ $INFOPATH == *: ]]; then
         infopath=${INFOPATH}${infopath}
-    elif [ ${INFOPATH:+set} ]; then
+    elif [[ ${INFOPATH:+set} ]]; then
         infopath=$INFOPATH
     fi
 
     infopath=$infopath:
-    if [ -n "$cur" ]; then
+    if [[ -n $cur ]]; then
         infopath="${infopath//://$cur* }"
     else
         infopath="${infopath//:// }"
@@ -62,9 +62,7 @@ _info()
     COMPREPLY=( ${COMPREPLY[@]##*/?(:)} )
     # weed out info dir file
     for (( i=0 ; i < ${#COMPREPLY[@]} ; ++i )); do
-        if [ "${COMPREPLY[$i]}" == 'dir' ]; then
-            unset COMPREPLY[$i]
-        fi
+        [[ ${COMPREPLY[$i]} == dir ]] && unset COMPREPLY[$i]
     done
     # strip suffix from info pages
     COMPREPLY=( ${COMPREPLY[@]%.@(gz|bz2|xz|lzma)} )
diff --git a/completions/invoke-rc.d b/completions/invoke-rc.d
index fd2c1db0..d4e0d245 100644
--- a/completions/invoke-rc.d
+++ b/completions/invoke-rc.d
@@ -9,8 +9,8 @@ _invoke_rc_d()
 
     local sysvdir services options valid_options
 
-    [ -d /etc/rc.d/init.d ] && sysvdir=/etc/rc.d/init.d \
-    || sysvdir=/etc/init.d
+    [[ -d /etc/rc.d/init.d ]] && sysvdir=/etc/rc.d/init.d \
+        || sysvdir=/etc/init.d
 
     services=( $( printf '%s ' $sysvdir/!(README*|*.sh|$_backup_glob) ) )
     services=( ${services[@]#$sysvdir/} )
@@ -24,7 +24,7 @@ _invoke_rc_d()
         | sort | uniq -u \
         ) )
     COMPREPLY=( $( compgen -W '${valid_options[@]} ${services[@]}' -- "$cur" ) )
-    elif [ -x $sysvdir/$prev ]; then
+    elif [[ -x $sysvdir/$prev ]]; then
         COMPREPLY=( $( compgen -W '`sed -e "y/|/ /" \
             -ne "s/^.*Usage:[ ]*[^ ]*[ ]*{*\([^}\"]*\).*$/\1/p" \
             $sysvdir/$prev`' -- "$cur" ) )
diff --git a/completions/ipmitool b/completions/ipmitool
index 81a6466f..281d9eac 100644
--- a/completions/ipmitool
+++ b/completions/ipmitool
@@ -71,11 +71,11 @@ _ipmitool()
     for (( i=1; i < ${#words[@]}-1; i++ )); do
         [[ -n $cmd ]] && subcmd=${words[i]} && break
         for c in ${cmds[@]}; do
-            [ ${words[i]} = $c ] && cmd=$c && break
+            [[ ${words[i]} == $c ]] && cmd=$c && break
         done
     done
 
-    if [ -z "$cmd" ]; then
+    if [[ -z $cmd ]]; then
         COMPREPLY=( $( compgen -W '${cmds[@]}' -- "$cur" ) )
         return 0
     fi
@@ -100,11 +100,11 @@ _ipmitool()
                 print|set)
                     ;;
                 alert)
-                    [ "$prev" = alert ] && \
+                    [[ $prev == alert ]] && \
                         COMPREPLY=( $( compgen -W 'print set' -- "$cur" ) )
                     ;;
                 stats)
-                    [ "$prev" = stats ] && \
+                    [[ $prev == stats ]] && \
                         COMPREPLY=( $( compgen -W 'print set' -- "$cur" ) )
                     ;;
                 *)
@@ -161,7 +161,7 @@ _ipmitool()
                     _filedir
                     ;;
                 time)
-                    [ "$prev" = time ] && \
+                    [[ $prev == time ]] && \
                         COMPREPLY=( $( compgen -W 'get set' -- "$cur" ) )
                     ;;
                 *)
@@ -176,7 +176,7 @@ _ipmitool()
                 summary|list|disable|enable|priv|test)
                     ;;
                 set)
-                    [ "$prev" = set ] && \
+                    [[ $prev == set ]] && \
                         COMPREPLY=( $( compgen -W 'name password' -- "$cur" ) )
                     ;;
                 *)
@@ -187,7 +187,7 @@ _ipmitool()
             ;;
 
         set)
-            [ "$prev" = set ] && \
+            [[ $prev == set ]] && \
                 COMPREPLY=( $( compgen -W 'hostname username password privlvl
                     authtype localaddr targetaddr port csv verbose' \
                         -- "$cur" ) )
diff --git a/completions/ipsec b/completions/ipsec
index 1a081028..a586a786 100644
--- a/completions/ipsec
+++ b/completions/ipsec
@@ -18,7 +18,7 @@ _ipsec_freeswan()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W 'auto barf eroute klipsdebug look manual \
             pluto ranbits rsasigkey setup showdefaults showhostkey spi spigrp \
             tncfg whack' -- "$cur" ) )
@@ -55,7 +55,7 @@ _ipsec_strongswan()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W 'down irdumm leases listaacerts listacerts \
             listalgs listall listcacerts listcainfos listcards listcerts \
             listcrls listgroups listocsp listocspcerts listpubkeys openac pki
diff --git a/completions/iptables b/completions/iptables
index b9314f23..5c4e0736 100644
--- a/completions/iptables
+++ b/completions/iptables
@@ -29,12 +29,12 @@ _iptables()
                 `iptables $table -nL | sed -ne "$chain" \
                 -e "s/INPUT|OUTPUT|FORWARD|PREROUTING|POSTROUTING//"`' -- \
                 "$cur" ) )
-        elif [ "$table" = "-t nat" ]; then
+        elif [[ $table == "-t nat" ]]; then
             COMPREPLY=( $( compgen -W 'ACCEPT DROP LOG ULOG REJECT \
                 MIRROR SNAT DNAT MASQUERADE `iptables $table -nL | \
                 sed -ne "$chain" -e "s/OUTPUT|PREROUTING|POSTROUTING//"`' \
                 -- "$cur" ) )
-        elif [ "$table" = "-t mangle" ]; then
+        elif [[ $table == "-t mangle" ]]; then
             COMPREPLY=( $( compgen -W 'ACCEPT DROP LOG ULOG REJECT \
                 MARK TOS `iptables $table -nL | sed -ne "$chain" \
                 -e "s/INPUT|OUTPUT|FORWARD|PREROUTING|POSTROUTING//"`' -- \
diff --git a/completions/isql b/completions/isql
index 695654f3..43cd6dd3 100644
--- a/completions/isql
+++ b/completions/isql
@@ -6,7 +6,7 @@ _isql()
     local cur prev words cword
     _init_completion || return
 
-    [ -f "$ODBCINI" ] \
+    [[ -f $ODBCINI ]] \
         && COMPREPLY=( $( command grep \\["$cur" "$ODBCINI" | tr -d \\[\\] ) )
 } &&
 complete -F _isql isql
diff --git a/completions/iwconfig b/completions/iwconfig
index 81dda723..899f1493 100644
--- a/completions/iwconfig
+++ b/completions/iwconfig
@@ -13,7 +13,7 @@ _iwconfig()
             ;;
         essid)
             COMPREPLY=( $( compgen -W 'on off any' -- "$cur" ) )
-            if [ -n "${COMP_IWLIST_SCAN:-}" ]; then
+            if [[ -n ${COMP_IWLIST_SCAN:-} ]]; then
                 COMPREPLY+=( $( compgen -W \
                     "$( iwlist ${words[1]} scan | \
                     awk -F'\"' '/ESSID/ {print $2}' )" -- "$cur" ) )
@@ -37,7 +37,7 @@ _iwconfig()
             ;;
         ap)
             COMPREPLY=( $( compgen -W 'on off any' -- "$cur" ) )
-            if [ -n "${COMP_IWLIST_SCAN:-}" ]; then
+            if [[ -n ${COMP_IWLIST_SCAN:-} ]]; then
                 COMPREPLY+=( $( compgen -W \
                     "$( iwlist ${words[1]} scan | \
                     awk -F ': ' '/Address/ {print $2}' )" -- "$cur" ) )
@@ -73,7 +73,7 @@ _iwconfig()
             ;;
     esac
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '--help --version' -- "$cur" ) )
         else
diff --git a/completions/iwlist b/completions/iwlist
index 39bfa0f1..7819b04d 100644
--- a/completions/iwlist
+++ b/completions/iwlist
@@ -5,7 +5,7 @@ _iwlist()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '--help --version' -- "$cur" ) )
         else
diff --git a/completions/iwpriv b/completions/iwpriv
index b0d45043..05952c5e 100644
--- a/completions/iwpriv
+++ b/completions/iwpriv
@@ -16,7 +16,7 @@ _iwpriv()
             ;;
     esac
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '--help --version' -- "$cur" ) )
         else
diff --git a/completions/iwspy b/completions/iwspy
index 4bffc76e..b59b0693 100644
--- a/completions/iwspy
+++ b/completions/iwspy
@@ -5,7 +5,7 @@ _iwspy()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         if [[ "$cur" == -* ]]; then
             COMPREPLY=( $( compgen -W '--help --version' -- "$cur" ) )
         else
diff --git a/completions/java b/completions/java
index e02f7369..c302d1e5 100644
--- a/completions/java
+++ b/completions/java
@@ -21,10 +21,10 @@ _java_find_classpath()
     done
 
     # default to environment
-    [ -z "$classpath" ] && classpath=$CLASSPATH
+    [[ -z $classpath ]] && classpath=$CLASSPATH
 
     # default to current directory
-    [ -z "$classpath" ] && classpath=.
+    [[ -z $classpath ]] && classpath=.
 }
 
 # exact sourcepath determination
@@ -41,7 +41,7 @@ _java_find_sourcepath()
     done
 
     # default to classpath
-    if [ -z "$sourcepath" ]; then
+    if [[ -z $sourcepath ]]; then
         local classpath
         _java_find_classpath
         sourcepath=$classpath
@@ -69,7 +69,7 @@ _java_classes()
                     command grep '^[^$]*\.class$' ) )
             fi
 
-        elif [ -d $i ]; then
+        elif [[ -d $i ]]; then
             COMPREPLY+=(
                 $( compgen -d -- "$i/$cur" | sed -e "s|^$i/\(.*\)|\1.|" )
                 $( compgen -f -X '!*.class' -- "$i/$cur" | \
@@ -101,7 +101,7 @@ _java_packages()
     cur=${cur//.//}
     # parse each sourcepath element for packages
     for i in ${sourcepath//:/ }; do
-        if [ -d $i ]; then
+        if [[ -d $i ]]; then
             COMPREPLY+=( $( command ls -F -d $i/$cur* 2>/dev/null | \
                 sed -e 's|^'$i'/||' ) )
         fi
diff --git a/completions/kldload b/completions/kldload
index 26ab0e19..f362db69 100644
--- a/completions/kldload
+++ b/completions/kldload
@@ -8,7 +8,7 @@ _kldload()
     _init_completion || return
 
     local moddir=/modules/
-    [ -d $moddir ] || moddir=/boot/kernel/
+    [[ -d $moddir ]] || moddir=/boot/kernel/
 
     compopt -o filenames
     COMPREPLY=( $( compgen -f "$moddir$cur" ) )
diff --git a/completions/links b/completions/links
index a212fa5a..5adc7de3 100644
--- a/completions/links
+++ b/completions/links
@@ -18,7 +18,7 @@ _links()
                 -source -version -help' -- "$cur" ) )
                 ;;
         *)
-            if [ -r ~/.links/links.his ]; then
+            if [[ -r ~/.links/links.his ]]; then
                 COMPREPLY=( $( compgen -W '$( < ~/.links/links.his )' \
                     -- "$cur" ) )
             fi
diff --git a/completions/lvm b/completions/lvm
index 7b353114..b657e0bd 100644
--- a/completions/lvm
+++ b/completions/lvm
@@ -314,7 +314,7 @@ _vgcreate()
             --verbose --version' -- "$cur" ) )
     else
         _args
-        if [ $args -eq 0 ]; then
+        if [[ $args -eq 0 ]]; then
             _volumegroups
         else
             _physicalvolumes
@@ -373,7 +373,7 @@ _vgreduce()
 
     else
         _args
-        if [ $args -eq 0 ]; then
+        if [[ $args -eq 0 ]]; then
             _volumegroups
         else
             _physicalvolumes
@@ -402,7 +402,7 @@ _vgextend()
         COMPREPLY=( $( compgen -W '$( _parse_usage "$1" --help )' -- "$cur" ) )
     else
         _args
-        if [ $args -eq 0 ]; then
+        if [[ $args -eq 0 ]]; then
             _volumegroups
         else
             _physicalvolumes
@@ -686,7 +686,7 @@ _lvcreate()
         COMPREPLY=( $( compgen -W '$( _parse_usage "$1" --help )' -- "$cur" ) )
     else
         _args
-        if [ $args -eq 0 ]; then
+        if [[ $args -eq 0 ]]; then
             _volumegroups
         else
             _physicalvolumes
@@ -779,7 +779,7 @@ _lvresize()
         COMPREPLY=( $( compgen -W '$( _parse_usage "$1" --help )' -- "$cur" ) )
     else
         _args
-        if [ $args -eq 0 ]; then
+        if [[ $args -eq 0 ]]; then
             _logicalvolumes
         else
             _physicalvolumes
@@ -808,7 +808,7 @@ _lvextend()
         COMPREPLY=( $( compgen -W '$( _parse_usage "$1" --help )' -- "$cur" ) )
     else
         _args
-        if [ $args -eq 0 ]; then
+        if [[ $args -eq 0 ]]; then
             _logicalvolumes
         else
             _physicalvolumes
@@ -822,7 +822,7 @@ _lvm()
     local cur prev words cword
     _init_completion || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W 'dumpconfig help lvchange \
             lvcreate lvdisplay lvextend lvmchange \
             lvmdiskscan lvmsadc lvmsar lvreduce \
diff --git a/completions/make b/completions/make
index 2c9a2c5a..32fad165 100644
--- a/completions/make
+++ b/completions/make
@@ -58,8 +58,8 @@ _make()
             fi
         done
 
-        [ -n "$makef" ] && makef="-f ${makef}"
-        [ -n "$makef_dir" ] && makef_dir="-C ${makef_dir}"
+        [[ -n $makef ]] && makef="-f ${makef}"
+        [[ -n $makef_dir ]] && makef_dir="-C ${makef_dir}"
 
         COMPREPLY=( $( compgen -W "$( make -qp $makef $makef_dir 2>/dev/null | \
             awk -F':' '/^[a-zA-Z0-9][^$#\/\t=]*:([^=]|$)/ \
diff --git a/completions/man b/completions/man
index 5c134d33..a9de57c4 100644
--- a/completions/man
+++ b/completions/man
@@ -63,7 +63,7 @@ _man()
         manpath=$MANPATH
     fi
 
-    if [ -z "$manpath" ]; then
+    if [[ -z $manpath ]]; then
         COMPREPLY=( $( compgen -c -- "$cur" ) )
         return 0
     fi
@@ -72,7 +72,7 @@ _man()
     [[ "$prev" == $mansect ]] && sect=$prev || sect='*'
 
     manpath=$manpath:
-    if [ -n "$cur" ]; then
+    if [[ -n $cur ]]; then
         manpath="${manpath//://*man$sect/$cur* } ${manpath//://*cat$sect/$cur* }"
     else
         manpath="${manpath//://*man$sect/ } ${manpath//://*cat$sect/ }"
diff --git a/completions/minicom b/completions/minicom
index 6bac50ba..cad90926 100644
--- a/completions/minicom
+++ b/completions/minicom
@@ -29,11 +29,10 @@ _minicom()
         return 0
     else
         local confdir
-        [ -n "$( command ls /etc/minirc.* 2>/dev/null)" ] \
-            && confdir=/etc
-        [ -n "$( command ls /etc/minicom/minirc.* 2>/dev/null)" ] \
+        [[ -n $( command ls /etc/minirc.* 2>/dev/null ) ]] && confdir=/etc
+        [[ -n $( command ls /etc/minicom/minirc.* 2>/dev/null ) ]] \
             && confdir=/etc/minicom
-        if [ -n "$confdir" ]; then
+        if [[ -n $confdir ]]; then
             COMPREPLY=( $( compgen -W '$( printf "%s\n" $confdir/minirc.* | \
                 sed -e "s|$confdir/minirc.||")' -- "$cur" ) )
             return 0
diff --git a/completions/mount b/completions/mount
index 48bc7b03..e1acef1e 100644
--- a/completions/mount
+++ b/completions/mount
@@ -92,7 +92,7 @@ _mount()
 
     if [[ "$cur" == *:* ]]; then
         for sm in "$(type -P showmount)" {,/usr}/{,s}bin/showmount; do
-            [ -x "$sm" ] || continue
+            [[ -x $sm ]] || continue
             COMPREPLY=( $( compgen -W "$( "$sm" -e ${cur%%:*} | \
                 awk 'NR>1 {print $1}' )" -- "${cur#*:}" ) )
             return 0
@@ -102,24 +102,24 @@ _mount()
     if [[ "$cur" == //* ]]; then
         host=${cur#//}
         host=${host%%/*}
-        if [ -n "$host" ]; then
+        if [[ -n $host ]]; then
             COMPREPLY=( $( compgen -P "//$host" -W \
                 "$( smbclient -d 0 -NL $host 2>/dev/null |
                 sed -ne '/^['"$'\t '"']*Sharename/,/^$/p' |
                 sed -ne '3,$s|^[^A-Za-z]*\([^'"$'\t '"']*\).*$|/\1|p' )" \
                     -- "${cur#//$host}" ) )
         fi
-    elif [ -r /etc/vfstab ]; then
+    elif [[ -r /etc/vfstab ]]; then
         # Solaris
         COMPREPLY=( $( compgen -W "$( awk '! /^[ \t]*#/ {if ($3 ~ /\//) print $3}' /etc/vfstab )" -- "$cur" ) )
-    elif [ ! -e /etc/fstab ]; then
+    elif [[ ! -e /etc/fstab ]]; then
         # probably Cygwin
         COMPREPLY=( $( compgen -W "$( mount | awk '! /^[ \t]*#/ {if ($3 ~ /\//) print $3}' )" -- "$cur" ) )
     else
         # probably Linux
-        if [ "$prev" = -L ]; then
+        if [[ $prev == -L ]]; then
             _linux_fstab -L < /etc/fstab
-        elif [ "$prev" = -U ]; then
+        elif [[ $prev == -U ]]; then
             COMPREPLY=( $( compgen -W '$(sed -ne "s/^[[:space:]]*UUID=\([^[:space:]]*\).*/\1/p" /etc/fstab )' -- "$cur" ) )
         else
             _linux_fstab < /etc/fstab
diff --git a/completions/mplayer b/completions/mplayer
index cd39d309..be852a5a 100644
--- a/completions/mplayer
+++ b/completions/mplayer
@@ -30,7 +30,7 @@ _mplayer()
             return 0
             ;;
         -font|-subfont)
-            if [ "$prev" = -font ]; then
+            if [[ $prev == -font ]]; then
                 _filedir '@(desc|ttf)'
             else
                 _filedir ttf
@@ -67,7 +67,7 @@ _mplayer()
             # if you don't have installed mplayer in /usr you
             # may want to set the MPLAYER_SKINS_DIR global variable
             local -a dirs
-            if [ -n "$MPLAYER_SKINS_DIR" ]; then
+            if [[ -n $MPLAYER_SKINS_DIR ]]; then
                 dirs=($MPLAYER_SKINS_DIR)
             else
                 dirs=(/usr/share/mplayer/skins /usr/local/share/mplayer/skins)
diff --git a/completions/mtx b/completions/mtx
index 0dae92ae..0cb63251 100644
--- a/completions/mtx
+++ b/completions/mtx
@@ -20,7 +20,7 @@ _mtx()
     drives=${drives//:Full}
     drives=${drives//:Empty}
 
-    if [ $cword -gt 1 ]; then
+    if [[ $cword -gt 1 ]]; then
         case $prev in
             load)
                 COMPREPLY=( $( compgen -W "$tapes" -- "$cur" ) )
diff --git a/completions/mutt b/completions/mutt
index f1fd6ff7..e840a4a9 100644
--- a/completions/mutt
+++ b/completions/mutt
@@ -21,23 +21,23 @@ _muttrc()
 {
     # Search COMP_WORDS for '-F muttrc' or '-Fmuttrc' argument
     set -- "${words[@]}"
-    while [ $# -gt 0 ]; do
+    while [[ $# -gt 0 ]]; do
         if [[ $1 == -F* ]]; then
-            if [ ${#1} -gt 2 ]; then
+            if [[ ${#1} -gt 2 ]]; then
                 muttrc="$(dequote "${1:2}")"
             else
                 shift
-                [ "$1" ] && muttrc="$(dequote "$1")"
+                [[ $1 ]] && muttrc="$(dequote "$1")"
             fi
             break
         fi
         shift
     done
 
-    if [ -z "$muttrc" ]; then
-        if [ -f ~/.${muttcmd}rc ]; then
+    if [[ -z $muttrc ]]; then
+        if [[ -f ~/.${muttcmd}rc ]]; then
             muttrc="~/.${muttcmd}rc"
-        elif [ -f ~/.${muttcmd}/${muttcmd}rc ]; then
+        elif [[ -f ~/.${muttcmd}/${muttcmd}rc ]]; then
             muttrc="~/.${muttcmd}/${muttcmd}rc"
         fi
     fi
@@ -77,7 +77,7 @@ _muttaliases()
     local -a conffiles aliases
 
     muttrc=$(_muttrc)
-    [ -z "$muttrc" ] && return 0
+    [[ -z $muttrc ]] && return 0
 
     conffiles=( $(eval _muttconffiles $muttrc $muttrc) )
     aliases=( $( sed -n 's|^alias[[:space:]]\{1,\}\([^[:space:]]\{1,\}\).*$|\1|p' \
@@ -125,10 +125,10 @@ _muttfiledir()
         COMPREPLY=( $( compgen -f -- "$folder/${cur:1}" ) )
         COMPREPLY=( ${COMPREPLY[@]#$folder/} )
         return 0
-    elif [ "$cur" == !* ]; then
+    elif [[ $cur == !* ]]; then
         spoolfile="$( $muttcmd -F "$muttrc" -Q spoolfile 2>/dev/null | \
             sed -e 's|^spoolfile=\"\(.*\)\"$|\1|' )"
-        [ ! -z "$spoolfile" ] && eval cur="${cur/^!/$spoolfile}"
+        [[ ! -z $spoolfile ]] && eval cur="${cur/^!/$spoolfile}"
     fi
     _filedir
 
diff --git a/completions/mysql b/completions/mysql
index effd313c..c41c1667 100644
--- a/completions/mysql
+++ b/completions/mysql
@@ -20,7 +20,7 @@ _mysql()
             return 0
             ;;
         --default-character-set)
-            [ -d /usr/share/mysql/charsets ] && \
+            [[ -d /usr/share/mysql/charsets ]] && \
                 COMPREPLY=( $( compgen -W "$(command ls /usr/share/mysql/charsets|sed -e '/^\(README\|Index\.xml\)$/d' -e 's/.xml$//') utf8" -- "$cur" ) )
             return 0
             ;;
diff --git a/completions/openssl b/completions/openssl
index 68a13c2a..b63d215d 100644
--- a/completions/openssl
+++ b/completions/openssl
@@ -13,14 +13,14 @@ _openssl_sections()
     done
 
     # if no config given, check some usual default locations
-    if [ -z "$config" ]; then
+    if [[ -z $config ]]; then
         for f in /etc/ssl/openssl.cnf /etc/pki/tls/openssl.cnf \
             /usr/share/ssl/openssl.cnf; do
-            [ -f $f ] && config=$f && break
+            [[ -f $f ]] && config=$f && break
         done
     fi
 
-    [ ! -f "$config" ] && return 0
+    [[ ! -f $config ]] && return 0
 
     COMPREPLY=( $( compgen -W "$( awk '/\[.*\]/ {print $2}' $config )" \
         -- "$cur" ) )
@@ -48,7 +48,7 @@ _openssl()
         rc2-40-cbc rc2-64-cbc rc2-cbc rc2-cfb rc2-ecb rc2-ofb rc4 \
         rc4-40'
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W "$commands" -- "$cur" ) )
     else
         command=${words[1]}
diff --git a/completions/p4 b/completions/p4
index 59d1bcd9..d0d984b2 100644
--- a/completions/p4
+++ b/completions/p4
@@ -14,9 +14,9 @@ _p4()
         uresource uxbinary xbinary xltext xtempobj xtext \
         text binary resource"
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W "$p4commands" -- "$cur" ) )
-    elif [ $cword -eq 2 ]; then
+    elif [[ $cword -eq 2 ]]; then
         case $prev in
             help)
                 COMPREPLY=( $( compgen -W "simple commands \
@@ -29,7 +29,7 @@ _p4()
             *)
                 ;;
         esac
-    elif [ $cword -gt 2 ]; then
+    elif [[ $cword -gt 2 ]]; then
         case $prev in
             -t)
                 case ${words[$cword-2]} in
diff --git a/completions/povray b/completions/povray
index e5ef9df6..fa2f9812 100644
--- a/completions/povray
+++ b/completions/povray
@@ -40,7 +40,7 @@ _povray()
         *.ini\[|*.ini\[*[^]]) # sections in .ini files
             cur="${povcur#*\[}"
             pfx="${povcur%\["$cur"}" # prefix == filename
-            [ -r "$pfx" ] || return 0
+            [[ -r $pfx ]] || return 0
             COMPREPLY=( $(sed -e 's/^[[:space:]]*\[\('"$cur"'[^]]*\]\).*$/\1/' \
                 -e 't' -e 'd' -- "$pfx") )
             # to prevent [bar] expand to nothing.  can be done more easily?
diff --git a/completions/psql b/completions/psql
index 7e4276bc..186177a3 100644
--- a/completions/psql
+++ b/completions/psql
@@ -13,7 +13,7 @@ _pg_users()
     # -w was introduced in 8.4, https://launchpad.net/bugs/164772
     COMPREPLY=( $( compgen -W "$( psql -Atqwc 'select usename from pg_user' \
         template1 2>/dev/null )" -- "$cur" ) )
-    [ ${#COMPREPLY[@]} -eq 0 ] && COMPREPLY=( $( compgen -u -- "$cur" ) )
+    [[ ${#COMPREPLY[@]} -eq 0 ]] && COMPREPLY=( $( compgen -u -- "$cur" ) )
 }
 
 # createdb(1) completion
diff --git a/completions/puppet b/completions/puppet
index 776c8492..66a81b3b 100644
--- a/completions/puppet
+++ b/completions/puppet
@@ -2,7 +2,7 @@
 
 _puppet_logdest()
 {
-    if [ -z "$cur" ]; then
+    if [[ -z $cur ]]; then
         COMPREPLY=( $( compgen -W 'syslog console /' -- "$cur" ) )
     else
         COMPREPLY=( $( compgen -W 'syslog console' -- "$cur" ) )
diff --git a/completions/qdbus b/completions/qdbus
index 5ed6bf89..a098fbc9 100644
--- a/completions/qdbus
+++ b/completions/qdbus
@@ -5,7 +5,7 @@ _qdbus()
     local cur prev words cword
     _init_completion || return
 
-    [ -n "$cur" ] && unset words[${#words[@]}-1]
+    [[ -n $cur ]] && unset words[${#words[@]}-1]
     COMPREPLY=( $( compgen -W '$( command ${words[@]} 2>/dev/null | \
         sed s/\(.*\)// )' -- "$cur" ) )
 } &&
diff --git a/completions/rcs b/completions/rcs
index a8eac85b..67c1c9d8 100644
--- a/completions/rcs
+++ b/completions/rcs
@@ -11,7 +11,7 @@ _rcs()
     dir=${cur%/*}
 
     # deal with relative directory
-    [ "$file" = "$dir" ] && dir=.
+    [[ $file == $dir ]] && dir=.
 
     COMPREPLY=( $( compgen -f "$dir/RCS/$file" ) )
 
diff --git a/completions/ri b/completions/ri
index 70756325..43f6408a 100644
--- a/completions/ri
+++ b/completions/ri
@@ -5,10 +5,10 @@ ri_get_methods()
 {
     local regex
 
-    if [ "$ri_version" = integrated ]; then
-        if [ -z "$separator" ]; then
+    if [[ $ri_version == integrated ]]; then
+        if [[ -z $separator ]]; then
             regex="(Instance|Class)"
-        elif [ "$separator" = "#" ]; then
+        elif [[ $separator == "#" ]]; then
             regex=Instance
         else
             regex=Class
@@ -45,7 +45,7 @@ _ri()
     # -W0 is required here to stop warnings from older versions of ri
     # from being captured when used with Ruby 1.8.1 and later
     ri_version="$(ruby -W0 $ri_path -v 2>&1)" || ri_version=integrated
-    [ "$ri_version" != "${ri_version%200*}" ] && ri_version=integrated
+    [[ $ri_version != ${ri_version%200*} ]] && ri_version=integrated
 
     # need to also split on commas
     IFS=$', \n\t'
@@ -60,11 +60,11 @@ _ri()
         return 0
     fi
 
-    if [ "$ri_version" = integrated ]; then
+    if [[ $ri_version == integrated ]]; then
         # integrated ri from Ruby 1.9
         classes=( $( ri -c 2>/dev/null | ruby -ne 'if /^\s*$/..$stdin.eof then \
         if /, [A-Z]+/ then print; end; end' 2>/dev/null ) )
-    elif [ "$ri_version" = "ri 1.8a" ]; then
+    elif [[ $ri_version == "ri 1.8a" ]]; then
         classes=( $( ruby -W0 $ri_path | \
             ruby -ne 'if /^'"'"'ri'"'"' has/..$stdin.eof then \
             if /^ .*[A-Z]/ then print; end; end' ))
diff --git a/completions/route b/completions/route
index 14fc2599..40d4f490 100644
--- a/completions/route
+++ b/completions/route
@@ -7,7 +7,7 @@ _route()
     local cur prev words cword
     _init_completion || return
 
-    if [ "$prev" = dev ]; then
+    if [[ $prev == dev ]]; then
         _available_interfaces
         return 0
     fi
@@ -18,7 +18,7 @@ _route()
         dyn reinstate dev default gw; do
         found=false
         for (( i=1; i < ${#words[@]}-1; i++ )); do
-            [ "${words[i]}" = "$opt" ] && found=true && break
+            [[ ${words[i]} == $opt ]] && found=true && break
         done
         $found || COMPREPLY[${#COMPREPLY[@]}]="$opt"
     done
diff --git a/completions/rpcdebug b/completions/rpcdebug
index 6d4acf52..3501af13 100644
--- a/completions/rpcdebug
+++ b/completions/rpcdebug
@@ -11,7 +11,7 @@ _rpcdebug_flags()
         fi
     done
 
-    if [ -n "$module" ]; then
+    if [[ -n $module ]]; then
         COMPREPLY=( $( compgen -W "$( rpcdebug -vh 2>&1 | \
             sed -ne 's/^'$module'[[:space:]]\{1,\}//p' )" -- "$cur" ) )
     fi
diff --git a/completions/rpm b/completions/rpm
index c7e67705..c73c59e9 100644
--- a/completions/rpm
+++ b/completions/rpm
@@ -48,7 +48,7 @@ _rpm()
     local cur prev words cword split
     _init_completion -s || return
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         # first parameter on line
         case $cur in
             --*)
diff --git a/completions/rrdtool b/completions/rrdtool
index 9280d8f5..8170c9fe 100644
--- a/completions/rrdtool
+++ b/completions/rrdtool
@@ -5,7 +5,7 @@ _rrdtool ()
     local cur prev words cword
     _init_completion || return
 
-    if [ ${#words[@]} -eq 2 ]; then
+    if [[ ${#words[@]} -eq 2 ]]; then
         COMPREPLY=( $( compgen -W 'create update updatev graph dump restore \
             last lastupdate first info fetch tune resize xport' -- "$cur" ) )
     else
diff --git a/completions/rsync b/completions/rsync
index e8b75b1a..e3f0f10e 100644
--- a/completions/rsync
+++ b/completions/rsync
@@ -74,7 +74,7 @@ _rsync()
                     break
                 fi
             done
-            [ "$shell" = ssh ] && _xfunc ssh _scp_remote_files
+            [[ $shell == ssh ]] && _xfunc ssh _scp_remote_files
             ;;
         *)
             _known_hosts_real -c -a "$cur"
diff --git a/completions/sbopkg b/completions/sbopkg
index 647355b0..d0bf9a2b 100644
--- a/completions/sbopkg
+++ b/completions/sbopkg
@@ -45,7 +45,7 @@ _sbopkg()
         fi
     done
 
-    if [ ! -r "$config" ]; then
+    if [[ ! -r $config ]]; then
         return 0
     fi
 
@@ -63,7 +63,7 @@ _sbopkg()
         esac
     done
 
-    if [ ! -r "$REPO_ROOT/$REPO_NAME/$REPO_BRANCH/SLACKBUILDS.TXT" ]; then
+    if [[ ! -r $REPO_ROOT/$REPO_NAME/$REPO_BRANCH/SLACKBUILDS.TXT ]]; then
         return 0
     fi
     COMPREPLY=( $( sed -ne "/^SLACKBUILD NAME: $cur/{s/^SLACKBUILD NAME: //;p}"\
diff --git a/completions/sitecopy b/completions/sitecopy
index 1f18514a..12480e97 100644
--- a/completions/sitecopy
+++ b/completions/sitecopy
@@ -40,7 +40,7 @@ _sitecopy()
             ;;
     esac
 
-    if [ -r ~/.sitecopyrc ]; then
+    if [[ -r ~/.sitecopyrc ]]; then
         COMPREPLY=( $( compgen -W "$($1 -v | \
                         command sed -n '/^Site:/s/Site: //p')" -- "$cur" ) )
     fi
diff --git a/completions/slackpkg b/completions/slackpkg
index 1d5759cb..9648d25a 100644
--- a/completions/slackpkg
+++ b/completions/slackpkg
@@ -43,7 +43,7 @@ _slackpkg()
     local confdir="/etc/slackpkg"
     local config="$confdir/slackpkg.conf"
 
-    if [ ! -r "$config" ]; then
+    if [[ ! -r $config ]]; then
         return 0
     fi
     . "$config"
@@ -62,7 +62,7 @@ _slackpkg()
             return 0
             ;;
         install-template|remove-template)
-            if [ -e "$confdir/templates" ]; then
+            if [[ -e $confdir/templates ]]; then
                 COMPREPLY=( $( cd "$confdir/templates"; \
                     compgen -f -X "!*.template" -- "$cur" ) )
                 COMPREPLY=( ${COMPREPLY[@]%.template} )
diff --git a/completions/slapt-get b/completions/slapt-get
index 99b50384..d18695cd 100644
--- a/completions/slapt-get
+++ b/completions/slapt-get
@@ -48,7 +48,7 @@ _slapt_get()
             break
         fi
     done
-    if [ ! -r "$config" ]; then
+    if [[ ! -r $config ]]; then
         return
     fi
 
diff --git a/completions/slapt-src b/completions/slapt-src
index 976ef65e..64b196e7 100644
--- a/completions/slapt-src
+++ b/completions/slapt-src
@@ -30,7 +30,7 @@ _slapt_src()
             break
         fi
     done
-    if [ "$t" != "all" ]; then
+    if [[ $t != all ]]; then
         return 0
     fi
 
@@ -42,7 +42,7 @@ _slapt_src()
             break
         fi
     done
-    if [ ! -r "$config" ]; then
+    if [[ ! -r $config ]]; then
         return 0
     fi
 
diff --git a/completions/smbclient b/completions/smbclient
index ceda7bbf..b7371907 100644
--- a/completions/smbclient
+++ b/completions/smbclient
@@ -7,14 +7,14 @@ _samba_resolve_order()
 
 _samba_domains()
 {
-    if [ -n "${COMP_SAMBA_SCAN:-}" ]; then
+    if [[ -n ${COMP_SAMBA_SCAN:-} ]]; then
         COMPREPLY=( $( compgen -W '$( smbtree -N -D )' -- "$cur" ) )
     fi
 }
 
 _samba_hosts()
 {
-    if [ -n "${COMP_SAMBA_SCAN:-}" ]; then
+    if [[ -n ${COMP_SAMBA_SCAN:-} ]]; then
         COMPREPLY=( $( compgen -W "$( smbtree -N -S | \
             sed -ne 's/^[[:space:]]*\\\\*\([^[:space:]]*\).*/\1/p' \
             )" -- $cur ) )
diff --git a/completions/ssh b/completions/ssh
index e62b13fd..a18ba494 100644
--- a/completions/ssh
+++ b/completions/ssh
@@ -157,20 +157,20 @@ _ssh()
     else
         # Search COMP_WORDS for '-F configfile' or '-Fconfigfile' argument
         set -- "${words[@]}"
-        while [ $# -gt 0 ]; do
+        while [[ $# -gt 0 ]]; do
             if [[ $1 == -F* ]]; then
-                if [ ${#1} -gt 2 ]; then
+                if [[ ${#1} -gt 2 ]]; then
                     configfile="$(dequote "${1:2}")"
                 else
                     shift
-                    [ "$1" ] && configfile="$(dequote "$1")"
+                    [[ $1 ]] && configfile="$(dequote "$1")"
                 fi
                 break
             fi
             shift
         done
         _known_hosts_real -a -F "$configfile" "$cur"
-        if [ $cword -ne 1 ]; then
+        if [[ $cword -ne 1 ]]; then
             compopt -o filenames
             COMPREPLY+=( $( compgen -c -- "$cur" ) )
         fi
@@ -220,13 +220,13 @@ _sftp()
     else
         # Search COMP_WORDS for '-F configfile' argument
         set -- "${words[@]}"
-        while [ $# -gt 0 ]; do
+        while [[ $# -gt 0 ]]; do
             if [[ $1 == -F* ]]; then
-                if [ ${#1} -gt 2 ]; then
+                if [[ ${#1} -gt 2 ]]; then
                     configfile="$(dequote "${1:2}")"
                 else
                     shift
-                    [ "$1" ] && configfile="$(dequote "$1")"
+                    [[ $1 ]] && configfile="$(dequote "$1")"
                 fi
                 break
             fi
@@ -258,12 +258,12 @@ _scp_remote_files()
     path=$( sed -e 's/\\\\\\\('$_scp_path_esc'\)/\\\1/g' <<<"$path" )
 
     # default to home dir of specified user on remote host
-    if [ -z "$path" ]; then
+    if [[ -z $path ]]; then
         path=$(ssh -o 'Batchmode yes' $userhost pwd 2>/dev/null)
     fi
 
     local files
-    if [ "$1" = -d ] ; then
+    if [[ $1 == -d ]]; then
         # escape problematic characters; remove non-dirs
         files=$( ssh -o 'Batchmode yes' $userhost \
             command ls -aF1d "$path*" 2>/dev/null | \
@@ -288,7 +288,7 @@ _scp_local_files()
     local IFS=$'\n'
 
     local dirsonly=false
-    if [ "$1" = -d ]; then
+    if [[ $1 == -d ]]; then
         dirsonly=true
         shift
     fi
@@ -350,13 +350,13 @@ _scp()
     else
         # Search COMP_WORDS for '-F configfile' or '-Fconfigfile' argument
         set -- "${words[@]}"
-        while [ $# -gt 0 ]; do
+        while [[ $# -gt 0 ]]; do
             if [[ $1 == -F* ]]; then
-                if [ ${#1} -gt 2 ]; then
+                if [[ ${#1} -gt 2 ]]; then
                     configfile="$(dequote "${1:2}")"
                 else
                     shift
-                    [ "$1" ] && configfile="$(dequote "$1")"
+                    [[ $1 ]] && configfile="$(dequote "$1")"
                 fi
                 break
             fi
diff --git a/completions/strace b/completions/strace
index 0ac4163a..9d28a54e 100644
--- a/completions/strace
+++ b/completions/strace
@@ -21,7 +21,7 @@ _strace()
         break
     done
 
-    if [ $offset -gt 0 ]; then
+    if [[ $offset -gt 0 ]]; then
         _command_offset $offset
     else
 
diff --git a/completions/tar b/completions/tar
index 9d1c56a4..45f3ff36 100644
--- a/completions/tar
+++ b/completions/tar
@@ -7,7 +7,7 @@ _tar()
 
     local ext regex tar untar
 
-    if [ $cword -eq 1 ]; then
+    if [[ $cword -eq 1 ]]; then
         COMPREPLY=( $( compgen -W 'c t x u r d A' -- "$cur" ) )
         return 0
     fi
diff --git a/completions/unace b/completions/unace
index 4ce5e370..369417ce 100644
--- a/completions/unace
+++ b/completions/unace
@@ -5,10 +5,10 @@ _unace()
     local cur prev words cword
     _init_completion || return
 
-    if [[ "$cur" == -* ]] ; then
+    if [[ $cur == -* ]]; then
         COMPREPLY=( $( compgen -W '-c -c- -f -f- -o -o- -p -y -y-' -- "$cur" ) )
     else
-        if [ $cword -eq 1 ]; then
+        if [[ $cword -eq 1 ]]; then
             COMPREPLY=( $( compgen -W 'e l t v x' -- "$cur" ) )
         else
             _filedir ace
diff --git a/completions/unrar b/completions/unrar
index d99e62fe..67a316ff 100644
--- a/completions/unrar
+++ b/completions/unrar
@@ -5,12 +5,12 @@ _unrar()
     local cur prev words cword
     _init_completion || return
 
-    if [[ "$cur" == -* ]] ; then
+    if [[ $cur == -* ]]; then
         COMPREPLY=( $( compgen -W '-ad -ap -av- -c- -cfg- -cl -cu \
             -dh -ep -f -idp -ierr -inul -kb -o+ -o- -ow -p -p- -r -ta \
             -tb -tn -to -u -v -ver -vp -x -x@ -y' -- "$cur" ) )
     else
-        if [ $cword -eq 1 ]; then
+        if [[ $cword -eq 1 ]]; then
             COMPREPLY=( $( compgen -W 'e l lb lt p t v vb vt x' -- "$cur" ) )
         else
             _filedir rar
diff --git a/completions/update-alternatives b/completions/update-alternatives
index 523e1de5..051b1142 100644
--- a/completions/update-alternatives
+++ b/completions/update-alternatives
@@ -5,7 +5,7 @@ _installed_alternatives()
     local admindir
     # find the admin dir
     for i in alternatives dpkg/alternatives rpm/alternatives; do
-        [ -d /var/lib/$i ] && admindir=/var/lib/$i && break
+        [[ -d /var/lib/$i ]] && admindir=/var/lib/$i && break
     done
     for (( i=1; i < cword; i++ )); do
         if [[ "${words[i]}" == --admindir ]]; then
diff --git a/completions/update-rc.d b/completions/update-rc.d
index b1d21e86..3dbad2e5 100644
--- a/completions/update-rc.d
+++ b/completions/update-rc.d
@@ -9,8 +9,8 @@ _update_rc_d()
 
     local sysvdir services options valid_options
 
-    [ -d /etc/rc.d/init.d ] && sysvdir=/etc/rc.d/init.d \
-    || sysvdir=/etc/init.d
+    [[ -d /etc/rc.d/init.d ]] && sysvdir=/etc/rc.d/init.d \
+        || sysvdir=/etc/init.d
 
     services=( $(printf '%s ' $sysvdir/!(README*|*.sh|$_backup_glob)) )
     services=( ${services[@]#$sysvdir/} )
diff --git a/completions/wodim b/completions/wodim
index 3bc304d1..b6ce2aa6 100644
--- a/completions/wodim
+++ b/completions/wodim
@@ -67,8 +67,8 @@ _cdrecord()
         -copy -nocopy -scms isrc= index= padsize= pregap= tsize= )
     # look if previous was either a file or a track option
     track_mode=0
-    if [ $cword -gt 1 ]; then
-        if [ -f "$prev" ]; then
+    if [[ $cword -gt 1 ]]; then
+        if [[ -f $prev ]]; then
             track_mode=1
         else
             for (( i=0; i < ${#track_options[@]}; i++ )); do
@@ -85,7 +85,7 @@ _cdrecord()
     # track options are always available
     COMPREPLY+=( $( compgen -W '${track_options[@]}' -- "$cur" ) )
     # general options are no more available after file or track option
-    if [ $track_mode -eq 0 ]; then
+    if [[ $track_mode -eq 0 ]]; then
         COMPREPLY+=( $( compgen -W '${generic_options[@]}' -- "$cur" ) )
     fi
     [[ $COMPREPLY == *= ]] && compopt -o nospace
diff --git a/completions/wtf b/completions/wtf
index b176d09b..cc8352f4 100644
--- a/completions/wtf
+++ b/completions/wtf
@@ -6,19 +6,19 @@ _wtf()
     local cur prev words cword
     _init_completion || return
 
-    [ "$prev" = -f ] && _filedir && return 0
-    [[ "$cur" == -* ]] && COMPREPLY=( -f ) && return 0
+    [[ $prev == -f ]] && _filedir && return 0
+    [[ $cur == -* ]] && COMPREPLY=( -f ) && return 0
 
     local db
 
     set -- "${words[@]}"
-    while [ $# -gt 0 ]; do
-        if [ "$1" = -f ]; then
+    while [[ $# -gt 0 ]]; do
+        if [[ $1 == -f ]]; then
             shift ; db=$1 ; break
         fi
         shift
     done
-    [ -z $db ] && db=${ACRONYMDB:-/usr/share/misc/acronyms*}
+    [[ -z $db ]] && db=${ACRONYMDB:-/usr/share/misc/acronyms*}
 
     COMPREPLY=( $( compgen -W "$( cut -f 1 -s $db ) -f" -- "${cur^^}" ) )
 } &&
diff --git a/doc/styleguide.txt b/doc/styleguide.txt
index 76b616ef..0f7ec254 100644
--- a/doc/styleguide.txt
+++ b/doc/styleguide.txt
@@ -29,13 +29,8 @@ doesn't confuse editors as bad as the latter, and is concise enough.
 &#91;[ ]] vs [ ]
 ----------------
 
-Use [[ ]] instead of [ ] when testing multiple conditions. [ ] is fine
-for single conditions where the syntax works.  Rationale: [[ ]] has
-short circuit behavior within one test containing multiple conditions
-separated by && or ||, while [ ] with -a or -o does not.  Thus it can
-be more efficient in some cases and may reduce need for nesting
-conditions, and it's cleaner to write for example [[ ... && ... ]]
-than [ ... ] && [ ... ], and in general [[ ]] has more features.
+Always use [[ ]] instead of [ ].  Rationale: the former is less error
+prone, more featureful, and slightly faster.
 
 Line wrapping
 -------------