如何將“source-highlight”與“git show”一起使用？

將source-highlight 與 less 結合使用效果非常好，但我很難了解如何使用它，git show因為沒有文件副檔名可以提示source-highlightgit 輸出中使用的語言……

less somefile.rb # result is syntax colourised
git show master:somefile.rb | less # no colouring

使用呼叫git show master:somefile.rb | less實際上與呼叫相同less somefile（即 no .rb）；因為沒有擴展，所以 source-highlight 無法猜測語法。

source-highlight 是否有非擴展方式來猜測，或者我可以以某種方式將--lang-def選項傳遞給LESSOPEN變數？

編輯 1 啊，所以看起來source-highlight 可以使用其他方法來推斷語言，但我的源文件中沒有這些方法。

我最終修改了 gnu source-highlight 的 src-hilite-lesspipe.sh 以便它可以處理管道文件：https ://gist.github.com/jaygooby/9494858d3d481a64819d227a9318f6c7

這意味著也以正常方式呼叫：

less code.py

您還可以為不具有source-highlight 使用的任何語言推理功能的無副檔名文件獲取原始碼突出顯示：

less /tmp/mycode

並且（這樣做的最初動機）管道文件：

cat /tmp/file.rb | less
git show master:obfusicated.perl # implicit pipe to less via git's pager

如果您知道您的程式碼使用 source-highlight 沒有任何定義文件的語法，則可以通過設置類似的語言來覆蓋猜測。c 通常是一個很好的備份：

SRCLANG=c git show master:app/views/layouts/application.html.erb

以下是要點的原始副本：https ://gist.github.com/jaygooby/9494858d3d481a64819d227a9318f6c7

#! /bin/bash
#
# Based on http://git.savannah.gnu.org/cgit/src-highlite.git/tree/src/src-hilite-lesspipe.sh.in
# by Lorenzo Bettini
#
# Modified by Jay Caines-Gooby to support piped files
# jay@gooby.org
# @jaygooby
#
# Typically called by setting:
#
# export LESSOPEN="|-/path/to/src-hilite-lesspipe.sh %s"
# export LESS=-R
#
# If we're less-ing a file, %s will be replaced by the name of the file. If
# there's no file and we're reading from a pipe, then %s is set to -
#
# This script differs from the original src-hilite-lesspipe.sh
# in that it can handle pipes and files with no extensions and will
# attempt to guess their language using the file command.
#
# So as well as invoking on regular files:
#
# less some.rb
# less some.py
#
# It will should be able to work on:
#
# less no-extension-but-contains-perl
#
# and even with more complex examples (my original motivation
# https://unix.stackexchange.com/questions/469982/how-can-i-use-source-highlight-with-git-show)
#
# git show master:some.rb
#
# It uses bashisms to do this, so is no longer a pure POSIX sh script.
set -eu

# Users can override the guessed language by setting SRCLANG:
# SRCLANG=c git show master:app/views/layouts/application.html.erb
SRCLANG=${SRCLANG:-}

guess_language() {
 lang=$(echo -e ${1:-} | file - | cut -d" " -f2)
 echo $(tr [A-Z] [a-z] <<< "$lang")
}

# check if the language passed as $1 is known to source-highlight
# In an earlier version of this script I set a fallback (c.lang)
# but this causes issues with paging man pages etc
check_language_is_known() {
 fallback=""
 lang=$(source-highlight --lang-list | cut -d' ' -f1 | grep "${1:-}" || true)
 lang=${lang:-$fallback}
 echo $lang
}

for source in "$@"; do
 case $source in
   *ChangeLog|*changelog)
     source-highlight --failsafe -f esc --lang-def=changelog.lang --style-file=esc.style -i "$source" ;;
   *Makefile|*makefile)
     source-highlight --failsafe -f esc --lang-def=makefile.lang --style-file=esc.style -i "$source" ;;
   *.tar|*.tgz|*.gz|*.bz2|*.xz)
     lesspipe "$source" ;;
   *)

     # naive check for a file extension; let source-highlight infer language
     # but only when source isn't - (ie. from a piped file)
     if [[ "$source" != "-" && $(basename "$source") =~ \. ]]; then
       source-highlight --failsafe --infer-lang -f esc --style-file=esc.style -i "$source"
     else
       # We're being piped to, or the filename doesn't have an extension
       # so guess the language.

       # When we're being piped to, we cat stdin, but when it's a file
       # without an extension, we cat the file instead.

       # unset IFS so line breaks are preserved and capture the file's contents
       # (will only work for files up to bash's available memory). There should
       # be a better way to replicate this with tee or process substitution...
       IFS= file=$([ "source" = "-" ] && cat || cat "$source")
       lang=$(guess_language $file)
       lang=$(check_language_is_known $lang)

       # Don't call if source-highlight doesn't know the language
       # BUT also let users override the guessed lang if the environment
       # variable SRCLANG is set. This can help where you know e.g. your
       # source code is c-like, but source-highlight has no specific syntax
       # definition for your code
       [ -n "$SRCLANG" ] && lang="$SRCLANG"

       if [ -n "$lang" ]; then
         echo $file | source-highlight --failsafe -f esc --src-lang=$lang --style-file=esc.style
       else
         echo $file
       fi
     fi

     ;;
 esac
done

引用自：https://unix.stackexchange.com/questions/469982