在bash中显示git提交统计信息

Question

我有脚本来显示我的repos的提交统计和合并统计，它们可以工作。我是为我的个人使用而写的，也是因为我有兴趣在我的git回复中找到趋势。

这个脚本报告有关提交的统计信息(数字、单词的平均长度等)。可以使用git-rev-list选项选择相关提交。

特征与时代

• count：提交的报告号(不是性能问题)
• len：以提交消息和提交散列(1561年提交)为单位的报告长度
• len min、len max和len avg：报告最小、最大或平均提交消息长度的单词和提交哈希(~10-15 s表示相同)

基准测试使用bash的time在我的dotfiles回购上运行

使用for-循环的一个以前的实施具有类似的性能.

显然，算法是O(n)。对于每天的使用来说，它们还是太慢了.

#! /usr/bin/env bash

set -euo pipefail

USAGE='[-h] (count | len [min|max|avg]) [rev-list options]

Display commit statistics
Filter commits based on [rev-list options]'
SUBDIRECTORY_OK=true

# source git-sh-setup for some helpers
set +u
source "$(git --exec-path)"/git-sh-setup
set -u

SIZER=(
  wc
  # count words
  -w
)

size() {
  local commit="$1"
  git log "$commit" -1 --format=%B | "${SIZER[@]}" | tr -d ' '
}

commits_list() {
  command=(
    git
    rev-list
    # start somewhere
    --all
  )
  if (($# > 0)) ; then
    command+=("$@")
  fi
  "${command[@]}" 2>/dev/null
}

commit_count() {
  commits_list "$@" | wc -l | tr -d ' '
}

commit_len() {
  commits_list "$@" |
    while read c ; do
      size "$c" | tr -d '[:space:]'
      printf ' %s\n' "$c"
    done
}

commit_len_min() {
  commit_len "$@" |
    sort -n |
    head -n 1
}

commit_len_max() {
  commit_len "$@" |
    sort -rn |
    head -n 1
}

commit_len_avg() {
  local num=0
  {
    printf '%s\n' '5k'
    while read c ; do
      ((++num))
      size "$c"
      ((num >= 2)) && printf '%s\n' '+'
    done < <(commits_list "$@")
    printf '%s\n' "$num" '/p'
  } | dc
}

main() {
  (($# >= 1)) || usage
  case "$1" in
    count) commit_count "${@:2}" ;;
    len)
      if (($# >= 2)); then
        case "$2" in
          max|min|avg) commit_len_"$2" "${@:3}" ;;
          *) commit_len "${@:2}" ;;
        esac
      else
        commit_len "${@:2}"
      fi
      ;;
    *) usage ;;
  esac
}

main "$@"

Shell脚本很难描述，我一直无法识别瓶颈(尽管commit_len似乎是一个很好的起点)。

我定期运行shellcheck。

Answer 1

通过将awk与一些创造性的格式结合起来，我成功地大大提高了性能:既然所有东西都是awk，即使我的1600次提交，脚本的速度也低于0.3s。

结果

#! /usr/bin/env bash

set -euo pipefail

USAGE='[-h] (count | len [min|max|avg]) [rev-list options]

Display commit statistics
Filter commits based on [rev-list options]'
SUBDIRECTORY_OK=true

# source git-sh-setup for some helpers
set +u
source "$(git --exec-path)"/git-sh-setup
set -u

commits_list() {
  command=(
    git
    log
    --pretty'='format:\a%n%H\t%s %b'
    # start somewhere
    --all
  )
  if (($# > 0)) ; then
    command+=("$@")
  fi
  "${command[@]}" |
    awk '
      /'\a''/ && NR != 1 { printf "\n"; next }
      { printf "%s ", $0 }
      END { printf "\n" }
      '
}

commit_count() {
  git rev-list --all --count "$@"
}

commit_len() {
  commits_list "$@" |
    awk -F\t' '{ print split($2,_," "), $1 }'
}

commit_len_min() {
  commit_len "$@" |
    sort -n |
    head -n 1
}

commit_len_max() {
  commit_len "$@" |
    sort -rn |
    head -n 1
}

commit_len_avg() {
  commit_len "$@" |
    awk '
      { sum += $1 }
      END { print sum/NR }
    '
}

main() {
  (($# >= 1)) || usage
  case "$1" in
    count) commit_count "${@:2}" ;;
    len)
      if (($# >= 2)); then
        case "$2" in
          max|min|avg) commit_len_"$2" "${@:3}" ;;
          *) commit_len "${@:2}" ;;
        esac
      else
        commit_len "${@:2}"
      fi
      ;;
    *) usage ;;
  esac
}

main "$@"