Inhaltsverzeichnis
Versionsverwaltung mit Git
GitLab
Für die Software-Verwaltung der Arbeitsgruppe wird das GitLab-System genutzt, das unter https://git.ps.informatik.uni-kiel.de/ erreichbar ist. Informationen zur Struktur und Verwendung von GitLab findet man in der GitLab-Beschreibung der Arbeitsgruppe.
Hier werden im folgenden nur einige Hinweise zur Benutzung von Git gegeben.
Benutzung von Git
Very nice and short tutorial:
http://www.kernel.org/pub/software/scm/git/docs/gittutorial.html
It is a good idea to introduce yourself to git with your name and public email address before doing any operation. The easiest way to do so is:
git config --global user.name "Michael Hanus" git config --global user.email mh@informatik.uni-kiel.de
Now, to get started: create a new project in Gitorious (ask the admin!) and clone it, e.g.,
git clone git@git.ps.informatik.uni-kiel.de/theses/2013-joe.git MyThesis
This creates a new directory MyThesis which can be managed by git. Go into this directory
cd MyThesis
The fastest way to work is git is to call
git gui
in the created directory, as that gui is simple and well designed. Normally you do not need command line information until after some getting used to the system.
Git Prompt
Der Git Prompt erleichtert es, beim Arbeiten mit Git zu wissen, in welcher Arbeitskopie eines Git Repositories man sich gerade befindet.
Folgende Datei muss unter ~/.git-prompt
erstellt werden:
# bash/zsh git prompt support # # Copyright (C) 2006,2007 Shawn O. Pearce <spearce@spearce.org> # Distributed under the GNU General Public License, version 2.0. # # This script allows you to see repository status in your prompt. # # To enable: # # 1) Copy this file to somewhere (e.g. ~/.git-prompt.sh). # 2) Add the following line to your .bashrc/.zshrc: # source ~/.git-prompt.sh # 3a) Change your PS1 to call __git_ps1 as # command-substitution: # Bash: PS1='[\u@\h \W$(__git_ps1 " (%s)")]\$ ' # ZSH: setopt PROMPT_SUBST ; PS1='[%n@%m %c$(__git_ps1 " (%s)")]\$ ' # the optional argument will be used as format string. # 3b) Alternatively, for a slightly faster prompt, __git_ps1 can # be used for PROMPT_COMMAND in Bash or for precmd() in Zsh # with two parameters, <pre> and <post>, which are strings # you would put in $PS1 before and after the status string # generated by the git-prompt machinery. e.g. # Bash: PROMPT_COMMAND='__git_ps1 "\u@\h:\w" "\\\$ "' # will show username, at-sign, host, colon, cwd, then # various status string, followed by dollar and SP, as # your prompt. # ZSH: precmd () { __git_ps1 "%n" ":%~$ " "|%s" } # will show username, pipe, then various status string, # followed by colon, cwd, dollar and SP, as your prompt. # Optionally, you can supply a third argument with a printf # format string to finetune the output of the branch status # # The repository status will be displayed only if you are currently in a # git repository. The %s token is the placeholder for the shown status. # # The prompt status always includes the current branch name. # # In addition, if you set GIT_PS1_SHOWDIRTYSTATE to a nonempty value, # unstaged (*) and staged (+) changes will be shown next to the branch # name. You can configure this per-repository with the # bash.showDirtyState variable, which defaults to true once # GIT_PS1_SHOWDIRTYSTATE is enabled. # # You can also see if currently something is stashed, by setting # GIT_PS1_SHOWSTASHSTATE to a nonempty value. If something is stashed, # then a '$' will be shown next to the branch name. # # If you would like to see if there're untracked files, then you can set # GIT_PS1_SHOWUNTRACKEDFILES to a nonempty value. If there're untracked # files, then a '%' will be shown next to the branch name. You can # configure this per-repository with the bash.showUntrackedFiles # variable, which defaults to true once GIT_PS1_SHOWUNTRACKEDFILES is # enabled. # # If you would like to see the difference between HEAD and its upstream, # set GIT_PS1_SHOWUPSTREAM="auto". A "<" indicates you are behind, ">" # indicates you are ahead, "<>" indicates you have diverged and "=" # indicates that there is no difference. You can further control # behaviour by setting GIT_PS1_SHOWUPSTREAM to a space-separated list # of values: # # verbose show number of commits ahead/behind (+/-) upstream # name if verbose, then also show the upstream abbrev name # legacy don't use the '--count' option available in recent # versions of git-rev-list # git always compare HEAD to @{upstream} # svn always compare HEAD to your SVN upstream # # By default, __git_ps1 will compare HEAD to your SVN upstream if it can # find one, or @{upstream} otherwise. Once you have set # GIT_PS1_SHOWUPSTREAM, you can override it on a per-repository basis by # setting the bash.showUpstream config variable. # # If you would like to see more information about the identity of # commits checked out as a detached HEAD, set GIT_PS1_DESCRIBE_STYLE # to one of these values: # # contains relative to newer annotated tag (v1.6.3.2~35) # branch relative to newer tag or branch (master~4) # describe relative to older annotated tag (v1.6.3.1-13-gdd42c2f) # default exactly matching tag # # If you would like a colored hint about the current dirty state, set # GIT_PS1_SHOWCOLORHINTS to a nonempty value. The colors are based on # the colored output of "git status -sb" and are available only when # using __git_ps1 for PROMPT_COMMAND or precmd. # check whether printf supports -v __git_printf_supports_v= printf -v __git_printf_supports_v -- '%s' yes >/dev/null 2>&1 # stores the divergence from upstream in $p # used by GIT_PS1_SHOWUPSTREAM __git_ps1_show_upstream () { local key value local svn_remote svn_url_pattern count n local upstream=git legacy="" verbose="" name="" svn_remote=() # get some config options from git-config local output="$(git config -z --get-regexp '^(svn-remote\..*\.url|bash\.showupstream)$' 2>/dev/null | tr '\0\n' '\n ')" while read -r key value; do case "$key" in bash.showupstream) GIT_PS1_SHOWUPSTREAM="$value" if [[ -z "${GIT_PS1_SHOWUPSTREAM}" ]]; then p="" return fi ;; svn-remote.*.url) svn_remote[$((${#svn_remote[@]} + 1))]="$value" svn_url_pattern="$svn_url_pattern\\|$value" upstream=svn+git # default upstream is SVN if available, else git ;; esac done <<< "$output" # parse configuration values for option in ${GIT_PS1_SHOWUPSTREAM}; do case "$option" in git|svn) upstream="$option" ;; verbose) verbose=1 ;; legacy) legacy=1 ;; name) name=1 ;; esac done # Find our upstream case "$upstream" in git) upstream="@{upstream}" ;; svn*) # get the upstream from the "git-svn-id: ..." in a commit message # (git-svn uses essentially the same procedure internally) local -a svn_upstream svn_upstream=($(git log --first-parent -1 \ --grep="^git-svn-id: \(${svn_url_pattern#??}\)" 2>/dev/null)) if [[ 0 -ne ${#svn_upstream[@]} ]]; then svn_upstream=${svn_upstream[${#svn_upstream[@]} - 2]} svn_upstream=${svn_upstream%@*} local n_stop="${#svn_remote[@]}" for ((n=1; n <= n_stop; n++)); do svn_upstream=${svn_upstream#${svn_remote[$n]}} done if [[ -z "$svn_upstream" ]]; then # default branch name for checkouts with no layout: upstream=${GIT_SVN_ID:-git-svn} else upstream=${svn_upstream#/} fi elif [[ "svn+git" = "$upstream" ]]; then upstream="@{upstream}" fi ;; esac # Find how many commits we are ahead/behind our upstream if [[ -z "$legacy" ]]; then count="$(git rev-list --count --left-right \ "$upstream"...HEAD 2>/dev/null)" else # produce equivalent output to --count for older versions of git local commits if commits="$(git rev-list --left-right "$upstream"...HEAD 2>/dev/null)" then local commit behind=0 ahead=0 for commit in $commits do case "$commit" in "<"*) ((behind++)) ;; *) ((ahead++)) ;; esac done count="$behind $ahead" else count="" fi fi # calculate the result if [[ -z "$verbose" ]]; then case "$count" in "") # no upstream p="" ;; "0 0") # equal to upstream p="=" ;; "0 "*) # ahead of upstream p=">" ;; *" 0") # behind upstream p="<" ;; *) # diverged from upstream p="<>" ;; esac else case "$count" in "") # no upstream p="" ;; "0 0") # equal to upstream p=" u=" ;; "0 "*) # ahead of upstream p=" u+${count#0 }" ;; *" 0") # behind upstream p=" u-${count% 0}" ;; *) # diverged from upstream p=" u+${count#* }-${count% *}" ;; esac if [[ -n "$count" && -n "$name" ]]; then __git_ps1_upstream_name=$(git rev-parse \ --abbrev-ref "$upstream" 2>/dev/null) if [ $pcmode = yes ]; then # see the comments around the # __git_ps1_branch_name variable below p="$p \${__git_ps1_upstream_name}" else p="$p ${__git_ps1_upstream_name}" # not needed anymore; keep user's # environment clean unset __git_ps1_upstream_name fi fi fi } # Helper function that is meant to be called from __git_ps1. It # injects color codes into the appropriate gitstring variables used # to build a gitstring. __git_ps1_colorize_gitstring () { if [[ -n ${ZSH_VERSION-} ]]; then local c_red='%F{red}' local c_green='%F{green}' local c_lblue='%F{blue}' local c_clear='%f' else # Using \[ and \] around colors is necessary to prevent # issues with command line editing/browsing/completion! local c_red='\[\e[31m\]' local c_green='\[\e[32m\]' local c_lblue='\[\e[1;34m\]' local c_clear='\[\e[0m\]' fi local bad_color=$c_red local ok_color=$c_green local flags_color="$c_lblue" local branch_color="" if [ $detached = no ]; then branch_color="$ok_color" else branch_color="$bad_color" fi c="$branch_color$c" z="$c_clear$z" if [ "$w" = "*" ]; then w="$bad_color$w" fi if [ -n "$i" ]; then i="$ok_color$i" fi if [ -n "$s" ]; then s="$flags_color$s" fi if [ -n "$u" ]; then u="$bad_color$u" fi r="$c_clear$r" } # __git_ps1 accepts 0 or 1 arguments (i.e., format string) # when called from PS1 using command substitution # in this mode it prints text to add to bash PS1 prompt (includes branch name) # # __git_ps1 requires 2 or 3 arguments when called from PROMPT_COMMAND (pc) # in that case it _sets_ PS1. The arguments are parts of a PS1 string. # when two arguments are given, the first is prepended and the second appended # to the state string when assigned to PS1. # The optional third parameter will be used as printf format string to further # customize the output of the git-status string. # In this mode you can request colored hints using GIT_PS1_SHOWCOLORHINTS=true __git_ps1 () { local pcmode=no local detached=no local ps1pc_start='\u@\h:\w ' local ps1pc_end='\$ ' local printf_format=' (%s)' case "$#" in 2|3) pcmode=yes ps1pc_start="$1" ps1pc_end="$2" printf_format="${3:-$printf_format}" ;; 0|1) printf_format="${1:-$printf_format}" ;; *) return ;; esac local repo_info rev_parse_exit_code repo_info="$(git rev-parse --git-dir --is-inside-git-dir \ --is-bare-repository --is-inside-work-tree \ --short HEAD 2>/dev/null)" rev_parse_exit_code="$?" if [ -z "$repo_info" ]; then if [ $pcmode = yes ]; then #In PC mode PS1 always needs to be set PS1="$ps1pc_start$ps1pc_end" fi return fi local short_sha if [ "$rev_parse_exit_code" = "0" ]; then short_sha="${repo_info##*$'\n'}" repo_info="${repo_info%$'\n'*}" fi local inside_worktree="${repo_info##*$'\n'}" repo_info="${repo_info%$'\n'*}" local bare_repo="${repo_info##*$'\n'}" repo_info="${repo_info%$'\n'*}" local inside_gitdir="${repo_info##*$'\n'}" local g="${repo_info%$'\n'*}" local r="" local b="" local step="" local total="" if [ -d "$g/rebase-merge" ]; then read b 2>/dev/null <"$g/rebase-merge/head-name" read step 2>/dev/null <"$g/rebase-merge/msgnum" read total 2>/dev/null <"$g/rebase-merge/end" if [ -f "$g/rebase-merge/interactive" ]; then r="|REBASE-i" else r="|REBASE-m" fi else if [ -d "$g/rebase-apply" ]; then read step 2>/dev/null <"$g/rebase-apply/next" read total 2>/dev/null <"$g/rebase-apply/last" if [ -f "$g/rebase-apply/rebasing" ]; then read b 2>/dev/null <"$g/rebase-apply/head-name" r="|REBASE" elif [ -f "$g/rebase-apply/applying" ]; then r="|AM" else r="|AM/REBASE" fi elif [ -f "$g/MERGE_HEAD" ]; then r="|MERGING" elif [ -f "$g/CHERRY_PICK_HEAD" ]; then r="|CHERRY-PICKING" elif [ -f "$g/REVERT_HEAD" ]; then r="|REVERTING" elif [ -f "$g/BISECT_LOG" ]; then r="|BISECTING" fi if [ -n "$b" ]; then : elif [ -h "$g/HEAD" ]; then # symlink symbolic ref b="$(git symbolic-ref HEAD 2>/dev/null)" else local head="" if ! read head 2>/dev/null <"$g/HEAD"; then if [ $pcmode = yes ]; then PS1="$ps1pc_start$ps1pc_end" fi return fi # is it a symbolic ref? b="${head#ref: }" if [ "$head" = "$b" ]; then detached=yes b="$( case "${GIT_PS1_DESCRIBE_STYLE-}" in (contains) git describe --contains HEAD ;; (branch) git describe --contains --all HEAD ;; (describe) git describe HEAD ;; (* | default) git describe --tags --exact-match HEAD ;; esac 2>/dev/null)" || b="$short_sha..." b="($b)" fi fi fi if [ -n "$step" ] && [ -n "$total" ]; then r="$r $step/$total" fi local w="" local i="" local s="" local u="" local c="" local p="" if [ "true" = "$inside_gitdir" ]; then if [ "true" = "$bare_repo" ]; then c="BARE:" else b="GIT_DIR!" fi elif [ "true" = "$inside_worktree" ]; then if [ -n "${GIT_PS1_SHOWDIRTYSTATE-}" ] && [ "$(git config --bool bash.showDirtyState)" != "false" ] then git diff --no-ext-diff --quiet --exit-code || w="*" if [ -n "$short_sha" ]; then git diff-index --cached --quiet HEAD -- || i="+" else i="#" fi fi if [ -n "${GIT_PS1_SHOWSTASHSTATE-}" ] && [ -r "$g/refs/stash" ]; then s="$" fi if [ -n "${GIT_PS1_SHOWUNTRACKEDFILES-}" ] && [ "$(git config --bool bash.showUntrackedFiles)" != "false" ] && git ls-files --others --exclude-standard --error-unmatch -- '*' >/dev/null 2>/dev/null then u="%${ZSH_VERSION+%}" fi if [ -n "${GIT_PS1_SHOWUPSTREAM-}" ]; then __git_ps1_show_upstream fi fi local z="${GIT_PS1_STATESEPARATOR-" "}" # NO color option unless in PROMPT_COMMAND mode if [ $pcmode = yes ] && [ -n "${GIT_PS1_SHOWCOLORHINTS-}" ]; then __git_ps1_colorize_gitstring fi b=${b##refs/heads/} if [ $pcmode = yes ]; then # In pcmode (and only pcmode) the contents of # $gitstring are subject to expansion by the shell. # Avoid putting the raw ref name in the prompt to # protect the user from arbitrary code execution via # specially crafted ref names (e.g., a ref named # '$(IFS=_;cmd=sudo_rm_-rf_/;$cmd)' would execute # 'sudo rm -rf /' when the prompt is drawn). Instead, # put the ref name in a new global variable (in the # __git_ps1_* namespace to avoid colliding with the # user's environment) and reference that variable from # PS1. __git_ps1_branch_name=$b # note that the $ is escaped -- the variable will be # expanded later (when it's time to draw the prompt) b="\${__git_ps1_branch_name}" fi local f="$w$i$s$u" local gitstring="$c$b${f:+$z$f}$r$p" if [ $pcmode = yes ]; then if [ "${__git_printf_supports_v-}" != yes ]; then gitstring=$(printf -- "$printf_format" "$gitstring") else printf -v gitstring -- "$printf_format" "$gitstring" fi PS1="$ps1pc_start$gitstring$ps1pc_end" else printf -- "$printf_format" "$gitstring" fi }
Und diese Datei muss beim Starten der Bash geladen werden (via .bashrc
):
if [ -r ~/.git-prompt ]; then . ~/.git-prompt PS1='[\u@\h \W$(__git_ps1 " (%s)")]\$ ' fi
Tricks und Kniffe
Zeilenumbrüche mit Unix und Windows
Während Windows Zeilenumbrüche durch ein CRLF darstellt (carriage return/line feed), nutzt Unix nur LF. Werden unterschiedliche Systeme für dasselbe Repository verwendet ist es also sinnvoll, eine automatische Konversion vorzunehmen. Vorgeschlagen wird Folgendes:
- intern wird LF verwendet
- Bei Unix-Systemen werden fälschlich eingecheckte CRLF beim Auschecken in LF umgewandelt
- Bei Windows-Systemen werden LF beim Auschecken in CRLF umgewandelt, beim Einchecken geschieht dies anders herum, CRLF werden in LF umgewandelt
Hierzu sollte man folgende Einstellung vornehmen:
Für Unix:
git config --global core.autocrlf input
Für Windows:
git config --global core.autocrlf true
Datei(en) aus Git Historie entfernen
Manchmal passiert es, dass man aus Versehen eine oder mehrere Dateien zum Repository hinzufügt. Auch wenn man diese anschließend wieder löscht bleiben sie dennoch in der Git Historie enthalten. Hat man beispielsweise ein bin
-Verzeichnis eingecheckt, kann dies sehr schnell diverse MiB bedeuten die jeder Nutzer mit auschecken muss.
Um diese aus der Historie komplett zu entfernen, kann man Folgendes tun, um das bin/
-Verzeichnis zu entfernen:
git filter-branch --index-filter 'git rm --cached --ignore-unmatch bin/'
Dieser Befehl entfernt den Unterordner aus der gesamten Historie. Soll die Historie erst ab einem bestimmten Commit verändert werden, geht dies mit:
git filter-branch --index-filter 'git rm --cached --ignore-unmatch bin/' -- abcd1234..^
wobei abcd1234
der entsprechende Commit ist.
Anschließend müssen noch entsprechende Verweise entfernt werden:
rm -Rf .git/refs/original rm -Rf .git/logs/ git gc git prune --expire now
Danach sind die Daten dauerhaft aus der Historie entfernt. Weitere Details finden sich in folgendem Artikel: Git Internals - Maintenance and Data Recovery
Farbiger Prompt
Auch wenn man gerne mit der Konsole arbeitet möchte man vielleicht etwas Farbe in seine Ausgabe bringen. Dies erreicht man einfach per:
git config --global color.ui true
Veraltete Remote Branches löschen
Durch folgenden Ablauf kann es passieren, dass man in seinem lokalen Repository eine Referenz zu einem gelöschten Remote Branch erhält:
$ git branch feature # neuen Feature Branch erstellen ... # Commits $ git push origin feature:feature # Branch zu Remote Repository hinzufügen ... # weitere Commits $ git checkout master # $ git merge feature # Feature Branch in master mergen $ git push origin :feature # Feature Branch im Remote Repository löschen $ git branch -D feature # Feature Branch lokal löschen
Nun ist der Remote Branch feature
aber lokal noch sichtbar:
$ git branch -a master remotes/origin/feature remotes/origin/master
Um solche Branches zu löschen hilft folgendes Kommando:
$ git remote prune origin --dry-run Pruning origin URL: <some url> * [would prune] origin/feature
Mit der Option –dry-run
wird nur angezeigt, was getan werden würde (nützlich zum Testen), ohne diese Option werden die Branches entfernt.
$ git remote prune origin Pruning origin URL: <some url> * [pruned] origin/feature
Ignorierte Dateien anzeigen
Möchte man sich die Dateien anzeigen lassen, die Git ignoriert (hilfreich z.B. zum Aufräumen), so hilft folgender Befehl:
git ls-files --others -i --exclude-standard
Alternativ geht auch:
git clean -ndX
Unterordner in separates Repository extrahieren
Angenommen man hat ein Repository, aus dem man einen Unterordner in ein separates Repository extrahieren möchte:
project/ - presentation/ - src/ - theses/
Wir wollen nun den Ordner src/
in ein neues Repository auslagern:
git clone <url> project-src cd project-src git filter-branch --subdirectory-filter src HEAD
Nach dem Auschecken filtern wir also alle Commits heraus, die nicht den Ordner src
betreffen, und die Inhalte werden aus src
in den Hauptordner verschoben.
Nun kann man noch ein bisschen aufräumen:
git reset --hard git gc --aggressive git prune
Remote-Tags löschen
You probably won't need to do this often (if ever at all) but just in case, here is how to delete a tag from a remote Git repository.
If you have a tag named 12345
then you would just do this:
git tag -d 12345 git push origin :refs/tags/12345
That will remove 12345
from the remote repository.