bash completion: Improve responsiveness of git-log completion

Junio noticed the bash completion has been taking a long time lately. Petr Baudis tracked it down to 72e5e989b ("bash: Add space after unique command name is completed."). Tracing the code showed we spent significant time inside of this loop within __gitcomp, due to the string copying overhead. [28.146109654] _git common over [28.164791148] gitrefs in [28.280302268] gitrefs dir out [28.300939737] gitcomp in [28.308378112] gitcomp pre-case * [28.313407453] gitcomp iter in * [28.701270296] gitcomp iter out [28.713370786] out normal Since __git_refs avoids this string copying by forking and using echo we use the same trick here when we need to finish generating the names for the caller. Signed-off-by: Shawn O. Pearce <spearce@spearce.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Shawn O. Pearce committed Jul 13, 2008 at 02:37 UTC ab02dfe533f55535bdb66e05776a4081020322c6

1 file changed +16 -12

contrib/completion/git-completion.bash

+16 -12

@@ -114,9 +114,20 @@ __git_ps1 ()

114 fi

115 }

116

117 +__gitcomp_1 ()

118 +{

119 + local c IFS=' '$'\t'$'\n'

120 + for c in $1; do

121 + case "$c$2" in

122 + --*=*) printf %s$'\n' "$c$2" ;;

123 + *.) printf %s$'\n' "$c$2" ;;

124 + *) printf %s$'\n' "$c$2 " ;;

125 + esac

126 + done

127 +}

128 +

129 __gitcomp ()

130 {

119 - local all c s=$'\n' IFS=' '$'\t'$'\n'

131 local cur="${COMP_WORDS[COMP_CWORD]}"

132 if [ $# -gt 2 ]; then

133 cur="$3"

@@ -124,21 +135,14 @@ __gitcomp ()

135 case "$cur" in

136 --*=)

137 COMPREPLY=()

127 - return

138 ;;

139 *)

130 - for c in $1; do

131 - case "$c$4" in

132 - --*=*) all="$all$c$4$s" ;;

133 - *.) all="$all$c$4$s" ;;

134 - *) all="$all$c$4 $s" ;;

135 - esac

136 - done

140 + local IFS=$'\n'

141 + COMPREPLY=($(compgen -P "$2" \

142 + -W "$(__gitcomp_1 "$1" "$4")" \

143 + -- "$cur"))

144 ;;

145 esac

139 - IFS=$s

140 - COMPREPLY=($(compgen -P "$2" -W "$all" -- "$cur"))

141 - return

146 }

147

148 __git_heads ()