ohmyzsh/plugins/scd/scd
2014-11-02 12:33:56 -05:00

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#!/bin/zsh -f
emulate -L zsh
local EXIT=return
if [[ $(whence -w $0) == *:' 'command ]]; then
emulate -R zsh
local RUNNING_AS_COMMAND=1
EXIT=exit
fi
local DOC='scd -- smart change to a recently used directory
usage: scd [options] [pattern1 pattern2 ...]
Go to a directory path that contains all fixed string patterns. Prefer
recent or frequently visited directories as found in the directory index.
Display a selection menu in case of multiple matches.
Options:
-a, --add add specified directories to the directory index.
--unindex remove current or specified directories from the index.
-r, --recursive apply options --add or --unindex recursively.
--alias=ALIAS create alias for the current or specified directory and
store it in ~/.scdalias.zsh.
--unalias remove ALIAS definition for the current or specified
directory from ~/.scdalias.zsh.
-A, --all include all matching directories. Disregard matching by
directory alias and filtering of less likely paths.
--list show matching directories and exit.
-v, --verbose display directory rank in the selection menu.
-h, --help display this message and exit.
'
local SCD_HISTFILE=${SCD_HISTFILE:-${HOME}/.scdhistory}
local SCD_HISTSIZE=${SCD_HISTSIZE:-5000}
local SCD_MENUSIZE=${SCD_MENUSIZE:-20}
local SCD_MEANLIFE=${SCD_MEANLIFE:-86400}
local SCD_THRESHOLD=${SCD_THRESHOLD:-0.005}
local SCD_SCRIPT=${RUNNING_AS_COMMAND:+$SCD_SCRIPT}
local SCD_ALIAS=~/.scdalias.zsh
local ICASE a d m p i maxrank threshold
local opt_help opt_add opt_unindex opt_recursive opt_verbose
local opt_alias opt_unalias opt_all opt_list
local -A drank dalias
local dmatching
local last_directory
setopt extendedhistory extendedglob noautonamedirs brace_ccl
# If SCD_SCRIPT is defined make sure the file exists and is empty.
# This removes any previous old commands.
[[ -n "$SCD_SCRIPT" ]] && [[ -s $SCD_SCRIPT || ! -f $SCD_SCRIPT ]] && (
umask 077
: >| $SCD_SCRIPT
)
# process command line options
zmodload -i zsh/zutil
zmodload -i zsh/datetime
zparseopts -D -- a=opt_add -add=opt_add -unindex=opt_unindex \
r=opt_recursive -recursive=opt_recursive \
-alias:=opt_alias -unalias=opt_unalias \
A=opt_all -all=opt_all -list=opt_list \
v=opt_verbose -verbose=opt_verbose h=opt_help -help=opt_help \
|| $EXIT $?
if [[ -n $opt_help ]]; then
print $DOC
$EXIT
fi
# load directory aliases if they exist
[[ -r $SCD_ALIAS ]] && source $SCD_ALIAS
# Private internal functions are prefixed with _scd_Y19oug_.
# Clean them up when the scd function returns.
setopt localtraps
trap 'unfunction -m "_scd_Y19oug_*"' EXIT
# works faster than the (:a) modifier and is compatible with zsh 4.2.6
_scd_Y19oug_abspath() {
set -A $1 ${(ps:\0:)"$(
unfunction -m "*"; shift
for d; do
cd $d && print -Nr -- $PWD && cd $OLDPWD
done
)"}
}
# define directory alias
if [[ -n $opt_alias ]]; then
if [[ -n $1 && ! -d $1 ]]; then
print -u2 "'$1' is not a directory."
$EXIT 1
fi
a=${opt_alias[-1]#=}
_scd_Y19oug_abspath d ${1:-$PWD}
# alias in the current shell, update alias file if successful
hash -d -- $a=$d &&
(
umask 077
hash -dr
[[ -r $SCD_ALIAS ]] && source $SCD_ALIAS
hash -d -- $a=$d
hash -dL >| $SCD_ALIAS
)
$EXIT $?
fi
# undefine directory alias
if [[ -n $opt_unalias ]]; then
if [[ -n $1 && ! -d $1 ]]; then
print -u2 "'$1' is not a directory."
$EXIT 1
fi
_scd_Y19oug_abspath a ${1:-$PWD}
a=$(print -rD ${a})
if [[ $a != [~][^/]## ]]; then
$EXIT
fi
a=${a#[~]}
# unalias in the current shell, update alias file if successful
if unhash -d -- $a 2>/dev/null && [[ -r $SCD_ALIAS ]]; then
(
umask 077
hash -dr
source $SCD_ALIAS
unhash -d -- $a 2>/dev/null &&
hash -dL >| $SCD_ALIAS
)
fi
$EXIT $?
fi
# The "compress" function collapses repeated directories to
# one entry with a time stamp that gives equivalent-probability.
_scd_Y19oug_compress() {
awk -v epochseconds=$EPOCHSECONDS -v meanlife=$SCD_MEANLIFE '
BEGIN { FS = "[:;]"; }
length($0) < 4096 && $2 > 0 {
tau = 1.0 * ($2 - epochseconds) / meanlife;
if (tau < -6.9078) tau = -6.9078;
prob = exp(tau);
sub(/^[^;]*;/, "");
if (NF) {
dlist[last[$0]] = "";
dlist[NR] = $0;
last[$0] = NR;
ptot[$0] += prob;
}
}
END {
for (i = 1; i <= NR; ++i) {
d = dlist[i];
if (d) {
ts = log(ptot[d]) * meanlife + epochseconds;
printf(": %.0f:0;%s\n", ts, d);
}
}
}
' $*
}
# Rewrite directory index if it is at least 20% oversized
if [[ -s $SCD_HISTFILE ]] && \
(( $(wc -l <$SCD_HISTFILE) > 1.2 * $SCD_HISTSIZE )); then
# compress repeated entries
m=( ${(f)"$(_scd_Y19oug_compress $SCD_HISTFILE)"} )
# purge non-existent directories
m=( ${(f)"$(
for a in $m; do
if [[ -d ${a#*;} ]]; then print -r -- $a; fi
done
)"}
)
# cut old entries if still oversized
if [[ $#m -gt $SCD_HISTSIZE ]]; then
m=( ${m[-$SCD_HISTSIZE,-1]} )
fi
print -lr -- $m >| ${SCD_HISTFILE}
fi
# Determine the last recorded directory
if [[ -s ${SCD_HISTFILE} ]]; then
last_directory=${"$(tail -1 ${SCD_HISTFILE})"#*;}
fi
# The "record" function adds its arguments to the directory index.
_scd_Y19oug_record() {
while [[ -n $last_directory && $1 == $last_directory ]]; do
shift
done
if [[ $# -gt 0 ]]; then
( umask 077
p=": ${EPOCHSECONDS}:0;"
print -lr -- ${p}${^*} >>| $SCD_HISTFILE )
fi
}
if [[ -n $opt_add ]]; then
for d; do
if [[ ! -d $d ]]; then
print -u2 "Directory '$d' does not exist."
$EXIT 2
fi
done
_scd_Y19oug_abspath m ${*:-$PWD}
_scd_Y19oug_record $m
if [[ -n $opt_recursive ]]; then
for d in $m; do
print -n "scanning ${d} ... "
_scd_Y19oug_record ${d}/**/*(-/N)
print "[done]"
done
fi
$EXIT
fi
# take care of removing entries from the directory index
if [[ -n $opt_unindex ]]; then
if [[ ! -s $SCD_HISTFILE ]]; then
$EXIT
fi
# expand existing directories in the argument list
for i in {1..$#}; do
if [[ -d ${argv[i]} ]]; then
_scd_Y19oug_abspath d ${argv[i]}
argv[i]=${d}
fi
done
m="$(awk -v recursive=${opt_recursive} '
BEGIN {
for (i = 2; i < ARGC; ++i) {
argset[ARGV[i]] = 1;
delete ARGV[i];
}
}
1 {
d = $0; sub(/^[^;]*;/, "", d);
if (d in argset) next;
}
recursive {
for (a in argset) {
if (substr(d, 1, length(a) + 1) == a"/") next;
}
}
{ print $0 }
' $SCD_HISTFILE ${*:-$PWD} )" || $EXIT $?
: >| ${SCD_HISTFILE}
[[ ${#m} == 0 ]] || print -r -- $m >> ${SCD_HISTFILE}
$EXIT
fi
# The "action" function is called when there is just one target directory.
_scd_Y19oug_action() {
cd $1 || return $?
if [[ -z $SCD_SCRIPT && -n $RUNNING_AS_COMMAND ]]; then
print -u2 "Warning: running as command with SCD_SCRIPT undefined."
fi
if [[ -n $SCD_SCRIPT ]]; then
print -r "cd ${(q)1}" >| $SCD_SCRIPT
fi
}
# Match and rank patterns to the index file
# set global arrays dmatching and drank
_scd_Y19oug_match() {
## single argument that is an existing directory or directory alias
if [[ -z $opt_all && $# == 1 ]] && \
[[ -d ${d::=$1} || -d ${d::=${nameddirs[$1]}} ]] && [[ -x $d ]];
then
_scd_Y19oug_abspath dmatching $d
drank[${dmatching[1]}]=1
return
fi
# ignore case unless there is an argument with an uppercase letter
[[ "$*" == *[[:upper:]]* ]] || ICASE='(#i)'
# support "$" as an anchor for the directory name ending
argv=( ${argv/(#m)?[$](#e)/${MATCH[1]}(#e)} )
# calculate rank of all directories in the SCD_HISTFILE and keep it as drank
# include a dummy entry for splitting of an empty string is buggy
[[ -s $SCD_HISTFILE ]] && drank=( ${(f)"$(
print -l /dev/null -10
<$SCD_HISTFILE \
awk -v epochseconds=$EPOCHSECONDS -v meanlife=$SCD_MEANLIFE '
BEGIN { FS = "[:;]"; }
length($0) < 4096 && $2 > 0 {
tau = 1.0 * ($2 - epochseconds) / meanlife;
if (tau < -6.9078) tau = -6.9078;
prob = exp(tau);
sub(/^[^;]*;/, "");
if (NF) ptot[$0] += prob;
}
END { for (di in ptot) { print di; print ptot[di]; } }'
)"}
)
unset "drank[/dev/null]"
# filter drank to the entries that match all arguments
for a; do
p=${ICASE}"*(${a})*"
drank=( ${(kv)drank[(I)${~p}]} )
done
# require at least one argument matches the directory name
p=${ICASE}"*(${(j:|:)argv})[^/]#"
drank=( ${(kv)drank[(I)${~p}]} )
# build a list of matching directories reverse-sorted by their probabilities
dmatching=( ${(f)"$(
for d p in ${(kv)drank}; do
print -r -- "$p $d";
done | sort -grk1 | cut -d ' ' -f 2-
)"}
)
# do not match $HOME or $PWD when run without arguments
if [[ $# == 0 ]]; then
dmatching=( ${dmatching:#(${HOME}|${PWD})} )
fi
# keep at most SCD_MENUSIZE of matching and valid directories
m=( )
for d in $dmatching; do
[[ ${#m} == $SCD_MENUSIZE ]] && break
[[ -d $d && -x $d ]] && m+=$d
done
dmatching=( $m )
# find the maximum rank
maxrank=0.0
for d in $dmatching; do
[[ ${drank[$d]} -lt maxrank ]] || maxrank=${drank[$d]}
done
# discard all directories below the rank threshold
threshold=$(( maxrank * SCD_THRESHOLD ))
if [[ -n ${opt_all} ]]; then
threshold=0
fi
dmatching=( ${^dmatching}(Ne:'(( ${drank[$REPLY]} >= threshold ))':) )
}
_scd_Y19oug_match $*
## process whatever directories that remained
if [[ ${#dmatching} == 0 ]]; then
print -u2 "No matching directory."
$EXIT 1
fi
## build formatted directory aliases for selection menu or list display
for d in $dmatching; do
if [[ -n ${opt_verbose} ]]; then
dalias[$d]=$(printf "%.3g %s" ${drank[$d]} $d)
else
dalias[$d]=$(print -Dr -- $d)
fi
done
## process the --list option
if [[ -n $opt_list ]]; then
for d in $dmatching; do
print -r -- "# ${dalias[$d]}"
print -r -- $d
done
$EXIT
fi
## process single directory match
if [[ ${#dmatching} == 1 ]]; then
_scd_Y19oug_action $dmatching
$EXIT $?
fi
## here we have multiple matches - display selection menu
a=( {a-z} {A-Z} )
a=( ${a[1,${#dmatching}]} )
p=( )
for i in {1..${#dmatching}}; do
[[ -n ${a[i]} ]] || break
p+="${a[i]}) ${dalias[${dmatching[i]}]}"
done
print -c -r -- $p
if read -s -k 1 d && [[ ${i::=${a[(I)$d]}} -gt 0 ]]; then
_scd_Y19oug_action ${dmatching[i]}
$EXIT $?
fi