git练习
从 https://jvns.ca/blog/2019/08/30/git-exercises--navigate-a-repository/ 看到的关于git的练习。
准备工作
git clone https://github.com/ruby/ruby ~/github/ruby
本次练习用到的子命令包括
- git checkout
- git log (--oneline, --author, and -S will be useful)
- git diff (--stat will be useful)
- git show
- git status
练习
对git不太熟悉,不能保证一定是正确的,而且还用到了除了git之外的工具. 如果有发现错误或者更好的实现方法,请不吝赐教,谢谢.
Check out matz’s commit of Ruby from 1998. The commit ID is 3db12e8b236ac8f88db8eb4690d10e4a3b8dbcd4. Find out how many lines of code Ruby was at that time.
git checkout 3db12e8b236ac8f88db8eb4690d10e4a3b8dbcd4 git branch
* (头指针分离于 3db12e8b23) masterCheck out the current master branch
git checkout master git branch
您的分支与上游分支 'origin/master' 一致。 * masterLook at the history for the file hash.c. What was the last commit ID that changed that file?
git log --oneline -n 1 hash.c
21994b7fd6 Avoid rehashing keys in transform_values
Get a diff of how hash.c has changed in the last 20ish years: compare that file on the master branch to the file at commit 3db12e8b236ac8f88db8eb4690d10e4a3b8dbcd4.
git diff master 3db12e8b236ac8f88db8eb4690d10e4a3b8dbcd4 hash.c |head -n 20
diff --git a/hash.c b/hash.c index e9d994bf70..fe9dfbaa26 100644 --- a/hash.c +++ b/hash.c @@ -1,6290 +1,1005 @@ -/********************************************************************** +/************************************************ hash.c - $Author$ + $Date$ created at: Mon Nov 22 18:51:18 JST 1993 - Copyright (C) 1993-2007 Yukihiro Matsumoto - Copyright (C) 2000 Network Applied Communication Laboratory, Inc. - Copyright (C) 2000 Information-technology Promotion Agency, Japan - -**********************************************************************/ -Find a recent commit that changed hash.c and look at the diff for that commit
lastchange=$(git log --oneline -n 2 hash.c |tail -n 1 |cut -f1 -d " ") git diff master ${lastchange} hash.c |head
diff --git a/hash.c b/hash.c index e9d994bf70..b61784af3a 100644 --- a/hash.c +++ b/hash.c @@ -3129,16 +3129,10 @@ rb_hash_transform_keys_bang(VALUE hash) } static int -transform_values_foreach_func(st_data_t key, st_data_t value, st_data_t argp, int error) +transform_values_i(VALUE key, VALUE value, VALUE result)This repository has a bunch of tags for every Ruby release. Get a list of all the tags.
git tag |head
REXML_2_7_0 SHELL_v0_6 forwardable_v1_1 gtk_012 irb_0_7_1 irb_0_7_3 irb_0_9 net_1_1_1 net_1_1_3 oniguruma_2_2_4
Find out how many files changed between tag v1_8_6_187 and tag v1_8_6_188
git diff v1_8_6_187 v1_8_6_188 --stat
ChangeLog | 10 ++++++++++ ext/Win32API/lib/win32/registry.rb | 2 +- ext/Win32API/lib/win32/resolv.rb | 2 +- lib/resolv.rb | 2 +- version.h | 2 +- 5 files changed, 14 insertions(+), 4 deletions(-)
Find a commit (any commit) from 2015 and check it out, look at the files very briefly, then go back to the master branch.
commit=$(git log --oneline -n 1 --until 2015-01-01 |cut -f1 -d " ") git checkout "${commit}" git branch ls |head git checkout master git branch
* (头指针分离于 d03c86391b) master addr2line.c addr2line.h array.c benchmark bignum.c bin bootstraptest BSDL ccan ChangeLog 您的分支与上游分支 'origin/master' 一致。 * master
Find out what commit the tag v1_8_6_187 corresponds to.
git rev-list -n 1 v1_8_6_187
928e6916b25aee5b2b379999a3fa8816d40db714
List the directory .git/refs/tags. Run cat .git/refs/tags/v1_8_6_187 to see the contents of one of those files.
ls .git/refs/tags echo ------------------------------------------- cat .git/refs/tags/v1_8_6_187-------------------------------------------
这个题目好奇怪,.git/refs/tags里居然是空的,感觉有什么地方不对
Find out what commit ID HEAD corresponds to right now.
git rev-list -n 1 HEAD
38069a3a55325757d2bba84191b006361a284cb0
Find out how many commits have been made to the test/ directory
git log --oneline -- test |wc -l
12370
Find out what commit ID HEAD corresponds to right now.
git rev-list -n 1 HEAD
38069a3a55325757d2bba84191b006361a284cb0
Get a diff of lib/telnet.rb between the commits 65a5162550f58047974793cdc8067a970b2435c0 and 9e3d9a2a009d2a0281802a84e1c5cc1c887edc71. How many lines of that file were changed?
git diff --stat 65a5162550f58047974793cdc8067a970b2435c0 9e3d9a2a009d2a0281802a84e1c5cc1c887edc71 -- lib/telnet.rb
lib/telnet.rb | 58 ++++++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 44 insertions(+), 14 deletions(-)How many commits were made between Ruby 2.5.1 and 2.5.2 (tags v2_5_1 and v2_5_3) (this one is a tiny bit tricky, there’s more than one step)
git log --oneline v2_5_1..v2_5_2 |wc -l
49
How many commits were authored by matz (Ruby’s creator)?
git log --oneline --author=matz |wc -l
2562
What’s the most recent commit that included the word tkutil?
git log -n 1 --grep tkutil
commit c285a4e3578c30b074f665e5f63283800fe3e157 Author: nobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> Date: Mon May 23 04:31:55 2016 +0000 remove unnecessary volatiles * ext/dbm/dbm.c (fdbm_initialize): used for rb_sys_fail_str. * ext/sdbm/init.c (fsdbm_initialize): ditto. * ext/tk/tcltklib.c (lib_do_one_event_core): no effect. * ext/tk/tkutil/tkutil.c (tk_eval_cmd, tk_get_eval_string): no effect if tail call optimized. * ext/tk/tkutil/tkutil.c (cbsubst_table_setup): set to const. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55127 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Check out the commit e51dca2596db9567bd4d698b18b4d300575d3881 and create a new branch that points at that commit.
git branch new e51dca2596db9567bd4d698b18b4d300575d3881 git branch
* master newRun git reflog to see all the navigating of the repository you’ve done so far
git reflog
5b1fd79ad9 HEAD@{0}: pull: Fast-forward 0e84eecc17 HEAD@{1}: pull: Fast-forward 142efba93e HEAD@{2}: pull: Fast-forward 2272efa463 HEAD@{3}: pull: Fast-forward c020fd6aa8 HEAD@{4}: pull: Fast-forward 70fd022a2a HEAD@{5}: pull: Fast-forward 38069a3a55 HEAD@{6}: checkout: moving from d03c86391b52e8470fb5b31c58ebc2422ec1653b to master d03c86391b HEAD@{7}: checkout: moving from master to d03c86391b 38069a3a55 HEAD@{8}: checkout: moving from master to master 38069a3a55 HEAD@{9}: checkout: moving from d03c86391b52e8470fb5b31c58ebc2422ec1653b to master d03c86391b HEAD@{10}: checkout: moving from master to d03c86391b 38069a3a55 HEAD@{11}: checkout: moving from d03c86391b52e8470fb5b31c58ebc2422ec1653b to master d03c86391b HEAD@{12}: checkout: moving from master to d03c86391b 38069a3a55 HEAD@{13}: checkout: moving from d03c86391b52e8470fb5b31c58ebc2422ec1653b to master d03c86391b HEAD@{14}: checkout: moving from master to d03c86391b 38069a3a55 HEAD@{15}: checkout: moving from d03c86391b52e8470fb5b31c58ebc2422ec1653b to master d03c86391b HEAD@{16}: checkout: moving from master to d03c86391b 38069a3a55 HEAD@{17}: pull: Fast-forward 0785469a40 HEAD@{18}: pull: Fast-forward 3bb1162cac HEAD@{19}: pull: Fast-forward 4a403e3f98 HEAD@{20}: pull: Fast-forward 6cad064424 HEAD@{21}: pull: Fast-forward 1edcfd6107 HEAD@{22}: pull: Fast-forward 8263459627 HEAD@{23}: pull: Fast-forward f41cd4ba43 HEAD@{24}: pull: Fast-forward b2c29bbab6 HEAD@{25}: pull: Fast-forward 7e0f56fb3d HEAD@{26}: pull: Fast-forward ac3e8834e0 HEAD@{27}: checkout: moving from 3db12e8b236ac8f88db8eb4690d10e4a3b8dbcd4 to master 3db12e8b23 HEAD@{28}: checkout: moving from master to 3db12e8b236ac8f88db8eb4690d10e4a3b8dbcd4 ac3e8834e0 HEAD@{29}: clone: from https://github.com/ruby/ruby
