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 734 </head>
 735 <body class="article">
 736 <div id="header">
 737 <h1>My First Contribution to the Git Project</h1>
 738 </div>
 739 <div id="content">
 740 <div class="sect1">
 741 <h2 id="summary">Summary</h2>
 742 <div class="sectionbody">
 743 <div class="paragraph"><p>This is a tutorial demonstrating the end-to-end workflow of creating a change to
 744 the Git tree, sending it for review, and making changes based on comments.</p></div>
 745 <div class="sect2">
 746 <h3 id="prerequisites">Prerequisites</h3>
 747 <div class="paragraph"><p>This tutorial assumes you&#8217;re already fairly familiar with using Git to manage
 748 source code.  The Git workflow steps will largely remain unexplained.</p></div>
 749 </div>
 750 <div class="sect2">
 751 <h3 id="related-reading">Related Reading</h3>
 752 <div class="paragraph"><p>This tutorial aims to summarize the following documents, but the reader may find
 753 useful additional context:</p></div>
 754 <div class="ulist"><ul>
 755 <li>
 756 <p>
 757 <code>Documentation/SubmittingPatches</code>
 758 </p>
 759 </li>
 760 <li>
 761 <p>
 762 <code>Documentation/howto/new-command.txt</code>
 763 </p>
 764 </li>
 765 </ul></div>
 766 </div>
 767 <div class="sect2">
 768 <h3 id="getting-help">Getting Help</h3>
 769 <div class="paragraph"><p>If you get stuck, you can seek help in the following places.</p></div>
 770 <div class="sect3">
 771 <h4 id="_a_href_mailto_git_vger_kernel_org_git_vger_kernel_org_a"><a href="mailto:git@vger.kernel.org">git@vger.kernel.org</a></h4>
 772 <div class="paragraph"><p>This is the main Git project mailing list where code reviews, version
 773 announcements, design discussions, and more take place. Those interested in
 774 contributing are welcome to post questions here. The Git list requires
 775 plain-text-only emails and prefers inline and bottom-posting when replying to
 776 mail; you will be CC&#8217;d in all replies to you. Optionally, you can subscribe to
 777 the list by sending an email to <a href="mailto:majordomo@vger.kernel.org">majordomo@vger.kernel.org</a> with "subscribe git"
 778 in the body. The <a href="https://lore.kernel.org/git">archive</a> of this mailing list is
 779 available to view in a browser.</p></div>
 780 </div>
 781 <div class="sect3">
 782 <h4 id="_a_href_https_groups_google_com_forum_forum_git_mentoring_git_mentoring_googlegroups_com_a"><a href="https://groups.google.com/forum/#!forum/git-mentoring">git-mentoring@googlegroups.com</a></h4>
 783 <div class="paragraph"><p>This mailing list is targeted to new contributors and was created as a place to
 784 post questions and receive answers outside of the public eye of the main list.
 785 Veteran contributors who are especially interested in helping mentor newcomers
 786 are present on the list. In order to avoid search indexers, group membership is
 787 required to view messages; anyone can join and no approval is required.</p></div>
 788 </div>
 789 <div class="sect3">
 790 <h4 id="_a_href_https_web_libera_chat_git_devel_git_devel_a_on_libera_chat"><a href="https://web.libera.chat/#git-devel">#git-devel</a> on Libera Chat</h4>
 791 <div class="paragraph"><p>This IRC channel is for conversations between Git contributors. If someone is
 792 currently online and knows the answer to your question, you can receive help
 793 in real time. Otherwise, you can read the
 794 <a href="https://colabti.org/irclogger/irclogger_logs/git-devel">scrollback</a> to see
 795 whether someone answered you. IRC does not allow offline private messaging, so
 796 if you try to private message someone and then log out of IRC, they cannot
 797 respond to you. It&#8217;s better to ask your questions in the channel so that you
 798 can be answered if you disconnect and so that others can learn from the
 799 conversation.</p></div>
 800 </div>
 801 </div>
 802 </div>
 803 </div>
 804 <div class="sect1">
 805 <h2 id="getting-started">Getting Started</h2>
 806 <div class="sectionbody">
 807 <div class="sect2">
 808 <h3 id="cloning">Clone the Git Repository</h3>
 809 <div class="paragraph"><p>Git is mirrored in a number of locations. Clone the repository from one of them;
 810 <a href="https://git-scm.com/downloads">https://git-scm.com/downloads</a> suggests one of the best places to clone from is
 811 the mirror on GitHub.</p></div>
 812 <div class="listingblock">
 813 <div class="content">
 814 <pre><code>$ git clone https://github.com/git/git git
 815 $ cd git</code></pre>
 816 </div></div>
 817 </div>
 818 <div class="sect2">
 819 <h3 id="dependencies">Installing Dependencies</h3>
 820 <div class="paragraph"><p>To build Git from source, you need to have a handful of dependencies installed
 821 on your system. For a hint of what&#8217;s needed, you can take a look at
 822 <code>INSTALL</code>, paying close attention to the section about Git&#8217;s dependencies on
 823 external programs and libraries. That document mentions a way to "test-drive"
 824 our freshly built Git without installing; that&#8217;s the method we&#8217;ll be using in
 825 this tutorial.</p></div>
 826 <div class="paragraph"><p>Make sure that your environment has everything you need by building your brand
 827 new clone of Git from the above step:</p></div>
 828 <div class="listingblock">
 829 <div class="content">
 830 <pre><code>$ make</code></pre>
 831 </div></div>
 832 <div class="admonitionblock">
 833 <table><tr>
 834 <td class="icon">
 835 <div class="title">Note</div>
 836 </td>
 837 <td class="content">The Git build is parallelizable. <code>-j#</code> is not included above but you can
 838 use it as you prefer, here and elsewhere.</td>
 839 </tr></table>
 840 </div>
 841 </div>
 842 <div class="sect2">
 843 <h3 id="identify-problem">Identify Problem to Solve</h3>
 844 <div class="paragraph"><p>In this tutorial, we will add a new command, <code>git psuh</code>, short for &#8220;Pony Saying
 845 &#8216;Um, Hello&#8221;&#8217; - a feature which has gone unimplemented despite a high frequency
 846 of invocation during users' typical daily workflow.</p></div>
 847 <div class="paragraph"><p>(We&#8217;ve seen some other effort in this space with the implementation of popular
 848 commands such as <code>sl</code>.)</p></div>
 849 </div>
 850 <div class="sect2">
 851 <h3 id="setup-workspace">Set Up Your Workspace</h3>
 852 <div class="paragraph"><p>Let&#8217;s start by making a development branch to work on our changes. Per
 853 <code>Documentation/SubmittingPatches</code>, since a brand new command is a new feature,
 854 it&#8217;s fine to base your work on <code>master</code>. However, in the future for bugfixes,
 855 etc., you should check that document and base it on the appropriate branch.</p></div>
 856 <div class="paragraph"><p>For the purposes of this document, we will base all our work on the <code>master</code>
 857 branch of the upstream project. Create the <code>psuh</code> branch you will use for
 858 development like so:</p></div>
 859 <div class="listingblock">
 860 <div class="content">
 861 <pre><code>$ git checkout -b psuh origin/master</code></pre>
 862 </div></div>
 863 <div class="paragraph"><p>We&#8217;ll make a number of commits here in order to demonstrate how to send a topic
 864 with multiple patches up for review simultaneously.</p></div>
 865 </div>
 866 </div>
 867 </div>
 868 <div class="sect1">
 869 <h2 id="code-it-up">Code It Up!</h2>
 870 <div class="sectionbody">
 871 <div class="admonitionblock">
 872 <table><tr>
 873 <td class="icon">
 874 <div class="title">Note</div>
 875 </td>
 876 <td class="content">A reference implementation can be found at
 877 <a href="https://github.com/nasamuffin/git/tree/psuh">https://github.com/nasamuffin/git/tree/psuh</a>.</td>
 878 </tr></table>
 879 </div>
 880 <div class="sect2">
 881 <h3 id="add-new-command">Adding a New Command</h3>
 882 <div class="paragraph"><p>Lots of the subcommands are written as builtins, which means they are
 883 implemented in C and compiled into the main <code>git</code> executable. Implementing the
 884 very simple <code>psuh</code> command as a built-in will demonstrate the structure of the
 885 codebase, the internal API, and the process of working together as a contributor
 886 with the reviewers and maintainer to integrate this change into the system.</p></div>
 887 <div class="paragraph"><p>Built-in subcommands are typically implemented in a function named "cmd_"
 888 followed by the name of the subcommand, in a source file named after the
 889 subcommand and contained within <code>builtin/</code>. So it makes sense to implement your
 890 command in <code>builtin/psuh.c</code>. Create that file, and within it, write the entry
 891 point for your command in a function matching the style and signature:</p></div>
 892 <div class="listingblock">
 893 <div class="content">
 894 <pre><code>int cmd_psuh(int argc, const char **argv, const char *prefix)</code></pre>
 895 </div></div>
 896 <div class="paragraph"><p>We&#8217;ll also need to add the declaration of psuh; open up <code>builtin.h</code>, find the
 897 declaration for <code>cmd_pull</code>, and add a new line for <code>psuh</code> immediately before it,
 898 in order to keep the declarations alphabetically sorted:</p></div>
 899 <div class="listingblock">
 900 <div class="content">
 901 <pre><code>int cmd_psuh(int argc, const char **argv, const char *prefix);</code></pre>
 902 </div></div>
 903 <div class="paragraph"><p>Be sure to <code>#include "builtin.h"</code> in your <code>psuh.c</code>.</p></div>
 904 <div class="paragraph"><p>Go ahead and add some throwaway printf to that function. This is a decent
 905 starting point as we can now add build rules and register the command.</p></div>
 906 <div class="admonitionblock">
 907 <table><tr>
 908 <td class="icon">
 909 <div class="title">Note</div>
 910 </td>
 911 <td class="content">Your throwaway text, as well as much of the text you will be adding over
 912 the course of this tutorial, is user-facing. That means it needs to be
 913 localizable. Take a look at <code>po/README</code> under "Marking strings for translation".
 914 Throughout the tutorial, we will mark strings for translation as necessary; you
 915 should also do so when writing your user-facing commands in the future.</td>
 916 </tr></table>
 917 </div>
 918 <div class="listingblock">
 919 <div class="content">
 920 <pre><code>int cmd_psuh(int argc, const char **argv, const char *prefix)
 921 {
 922         printf(_("Pony saying hello goes here.\n"));
 923         return 0;
 924 }</code></pre>
 925 </div></div>
 926 <div class="paragraph"><p>Let&#8217;s try to build it.  Open <code>Makefile</code>, find where <code>builtin/pull.o</code> is added
 927 to <code>BUILTIN_OBJS</code>, and add <code>builtin/psuh.o</code> in the same way next to it in
 928 alphabetical order. Once you&#8217;ve done so, move to the top-level directory and
 929 build simply with <code>make</code>. Also add the <code>DEVELOPER=1</code> variable to turn on
 930 some additional warnings:</p></div>
 931 <div class="listingblock">
 932 <div class="content">
 933 <pre><code>$ echo DEVELOPER=1 &gt;config.mak
 934 $ make</code></pre>
 935 </div></div>
 936 <div class="admonitionblock">
 937 <table><tr>
 938 <td class="icon">
 939 <div class="title">Note</div>
 940 </td>
 941 <td class="content">When you are developing the Git project, it&#8217;s preferred that you use the
 942 <code>DEVELOPER</code> flag; if there&#8217;s some reason it doesn&#8217;t work for you, you can turn
 943 it off, but it&#8217;s a good idea to mention the problem to the mailing list.</td>
 944 </tr></table>
 945 </div>
 946 <div class="paragraph"><p>Great, now your new command builds happily on its own. But nobody invokes it.
 947 Let&#8217;s change that.</p></div>
 948 <div class="paragraph"><p>The list of commands lives in <code>git.c</code>. We can register a new command by adding
 949 a <code>cmd_struct</code> to the <code>commands[]</code> array. <code>struct cmd_struct</code> takes a string
 950 with the command name, a function pointer to the command implementation, and a
 951 setup option flag. For now, let&#8217;s keep mimicking <code>push</code>. Find the line where
 952 <code>cmd_push</code> is registered, copy it, and modify it for <code>cmd_psuh</code>, placing the new
 953 line in alphabetical order (immediately before <code>cmd_pull</code>).</p></div>
 954 <div class="paragraph"><p>The options are documented in <code>builtin.h</code> under "Adding a new built-in." Since
 955 we hope to print some data about the user&#8217;s current workspace context later,
 956 we need a Git directory, so choose <code>RUN_SETUP</code> as your only option.</p></div>
 957 <div class="paragraph"><p>Go ahead and build again. You should see a clean build, so let&#8217;s kick the tires
 958 and see if it works. There&#8217;s a binary you can use to test with in the
 959 <code>bin-wrappers</code> directory.</p></div>
 960 <div class="listingblock">
 961 <div class="content">
 962 <pre><code>$ ./bin-wrappers/git psuh</code></pre>
 963 </div></div>
 964 <div class="paragraph"><p>Check it out! You&#8217;ve got a command! Nice work! Let&#8217;s commit this.</p></div>
 965 <div class="paragraph"><p><code>git status</code> reveals modified <code>Makefile</code>, <code>builtin.h</code>, and <code>git.c</code> as well as
 966 untracked <code>builtin/psuh.c</code> and <code>git-psuh</code>. First, let&#8217;s take care of the binary,
 967 which should be ignored. Open <code>.gitignore</code> in your editor, find <code>/git-pull</code>, and
 968 add an entry for your new command in alphabetical order:</p></div>
 969 <div class="listingblock">
 970 <div class="content">
 971 <pre><code>...
 972 /git-prune-packed
 973 /git-psuh
 974 /git-pull
 975 /git-push
 976 /git-quiltimport
 977 /git-range-diff
 978 ...</code></pre>
 979 </div></div>
 980 <div class="paragraph"><p>Checking <code>git status</code> again should show that <code>git-psuh</code> has been removed from
 981 the untracked list and <code>.gitignore</code> has been added to the modified list. Now we
 982 can stage and commit:</p></div>
 983 <div class="listingblock">
 984 <div class="content">
 985 <pre><code>$ git add Makefile builtin.h builtin/psuh.c git.c .gitignore
 986 $ git commit -s</code></pre>
 987 </div></div>
 988 <div class="paragraph"><p>You will be presented with your editor in order to write a commit message. Start
 989 the commit with a 50-column or less subject line, including the name of the
 990 component you&#8217;re working on, followed by a blank line (always required) and then
 991 the body of your commit message, which should provide the bulk of the context.
 992 Remember to be explicit and provide the "Why" of your change, especially if it
 993 couldn&#8217;t easily be understood from your diff. When editing your commit message,
 994 don&#8217;t remove the <code>Signed-off-by</code> trailer which was added by <code>-s</code> above.</p></div>
 995 <div class="listingblock">
 996 <div class="content">
 997 <pre><code>psuh: add a built-in by popular demand
 998
 999 Internal metrics indicate this is a command many users expect to be
1000 present. So here's an implementation to help drive customer
1001 satisfaction and engagement: a pony which doubtfully greets the user,
1002 or, a Pony Saying "Um, Hello" (PSUH).
1003
1004 This commit message is intentionally formatted to 72 columns per line,
1005 starts with a single line as "commit message subject" that is written as
1006 if to command the codebase to do something (add this, teach a command
1007 that). The body of the message is designed to add information about the
1008 commit that is not readily deduced from reading the associated diff,
1009 such as answering the question "why?".
1010
1011 Signed-off-by: A U Thor &lt;author@example.com&gt;</code></pre>
1012 </div></div>
1013 <div class="paragraph"><p>Go ahead and inspect your new commit with <code>git show</code>. "psuh:" indicates you
1014 have modified mainly the <code>psuh</code> command. The subject line gives readers an idea
1015 of what you&#8217;ve changed. The sign-off line (<code>-s</code>) indicates that you agree to
1016 the Developer&#8217;s Certificate of Origin 1.1 (see the
1017 <code>Documentation/SubmittingPatches</code> [[dco]] header).</p></div>
1018 <div class="paragraph"><p>For the remainder of the tutorial, the subject line only will be listed for the
1019 sake of brevity. However, fully-fleshed example commit messages are available
1020 on the reference implementation linked at the top of this document.</p></div>
1021 </div>
1022 <div class="sect2">
1023 <h3 id="implementation">Implementation</h3>
1024 <div class="paragraph"><p>It&#8217;s probably useful to do at least something besides printing out a string.
1025 Let&#8217;s start by having a look at everything we get.</p></div>
1026 <div class="paragraph"><p>Modify your <code>cmd_psuh</code> implementation to dump the args you&#8217;re passed, keeping
1027 existing <code>printf()</code> calls in place:</p></div>
1028 <div class="listingblock">
1029 <div class="content">
1030 <pre><code>        int i;
1031
1032         ...
1033
1034         printf(Q_("Your args (there is %d):\n",
1035                   "Your args (there are %d):\n",
1036                   argc),
1037                argc);
1038         for (i = 0; i &lt; argc; i++)
1039                 printf("%d: %s\n", i, argv[i]);
1040
1041         printf(_("Your current working directory:\n&lt;top-level&gt;%s%s\n"),
1042                prefix ? "/" : "", prefix ? prefix : "");</code></pre>
1043 </div></div>
1044 <div class="paragraph"><p>Build and try it. As you may expect, there&#8217;s pretty much just whatever we give
1045 on the command line, including the name of our command. (If <code>prefix</code> is empty
1046 for you, try <code>cd Documentation/ &amp;&amp; ../bin-wrappers/git psuh</code>). That&#8217;s not so
1047 helpful. So what other context can we get?</p></div>
1048 <div class="paragraph"><p>Add a line to <code>#include "config.h"</code>. Then, add the following bits to the
1049 function body:</p></div>
1050 <div class="listingblock">
1051 <div class="content">
1052 <pre><code>        const char *cfg_name;
1053
1054 ...
1055
1056         git_config(git_default_config, NULL);
1057         if (git_config_get_string_tmp("user.name", &amp;cfg_name) &gt; 0)
1058                 printf(_("No name is found in config\n"));
1059         else
1060                 printf(_("Your name: %s\n"), cfg_name);</code></pre>
1061 </div></div>
1062 <div class="paragraph"><p><code>git_config()</code> will grab the configuration from config files known to Git and
1063 apply standard precedence rules. <code>git_config_get_string_tmp()</code> will look up
1064 a specific key ("user.name") and give you the value. There are a number of
1065 single-key lookup functions like this one; you can see them all (and more info
1066 about how to use <code>git_config()</code>) in <code>Documentation/technical/api-config.txt</code>.</p></div>
1067 <div class="paragraph"><p>You should see that the name printed matches the one you see when you run:</p></div>
1068 <div class="listingblock">
1069 <div class="content">
1070 <pre><code>$ git config --get user.name</code></pre>
1071 </div></div>
1072 <div class="paragraph"><p>Great! Now we know how to check for values in the Git config. Let&#8217;s commit this
1073 too, so we don&#8217;t lose our progress.</p></div>
1074 <div class="listingblock">
1075 <div class="content">
1076 <pre><code>$ git add builtin/psuh.c
1077 $ git commit -sm "psuh: show parameters &amp; config opts"</code></pre>
1078 </div></div>
1079 <div class="admonitionblock">
1080 <table><tr>
1081 <td class="icon">
1082 <div class="title">Note</div>
1083 </td>
1084 <td class="content">Again, the above is for sake of brevity in this tutorial. In a real change
1085 you should not use <code>-m</code> but instead use the editor to write a meaningful
1086 message.</td>
1087 </tr></table>
1088 </div>
1089 <div class="paragraph"><p>Still, it&#8217;d be nice to know what the user&#8217;s working context is like. Let&#8217;s see
1090 if we can print the name of the user&#8217;s current branch. We can mimic the
1091 <code>git status</code> implementation; the printer is located in <code>wt-status.c</code> and we can
1092 see that the branch is held in a <code>struct wt_status</code>.</p></div>
1093 <div class="paragraph"><p><code>wt_status_print()</code> gets invoked by <code>cmd_status()</code> in <code>builtin/commit.c</code>.
1094 Looking at that implementation we see the status config being populated like so:</p></div>
1095 <div class="listingblock">
1096 <div class="content">
1097 <pre><code>status_init_config(&amp;s, git_status_config);</code></pre>
1098 </div></div>
1099 <div class="paragraph"><p>But as we drill down, we can find that <code>status_init_config()</code> wraps a call
1100 to <code>git_config()</code>. Let&#8217;s modify the code we wrote in the previous commit.</p></div>
1101 <div class="paragraph"><p>Be sure to include the header to allow you to use <code>struct wt_status</code>:</p></div>
1102 <div class="listingblock">
1103 <div class="content">
1104 <pre><code>#include "wt-status.h"</code></pre>
1105 </div></div>
1106 <div class="paragraph"><p>Then modify your <code>cmd_psuh</code> implementation to declare your <code>struct wt_status</code>,
1107 prepare it, and print its contents:</p></div>
1108 <div class="listingblock">
1109 <div class="content">
1110 <pre><code>        struct wt_status status;
1111
1112 ...
1113
1114         wt_status_prepare(the_repository, &amp;status);
1115         git_config(git_default_config, &amp;status);
1116
1117 ...
1118
1119         printf(_("Your current branch: %s\n"), status.branch);</code></pre>
1120 </div></div>
1121 <div class="paragraph"><p>Run it again. Check it out - here&#8217;s the (verbose) name of your current branch!</p></div>
1122 <div class="paragraph"><p>Let&#8217;s commit this as well.</p></div>
1123 <div class="listingblock">
1124 <div class="content">
1125 <pre><code>$ git add builtin/psuh.c
1126 $ git commit -sm "psuh: print the current branch"</code></pre>
1127 </div></div>
1128 <div class="paragraph"><p>Now let&#8217;s see if we can get some info about a specific commit.</p></div>
1129 <div class="paragraph"><p>Luckily, there are some helpers for us here. <code>commit.h</code> has a function called
1130 <code>lookup_commit_reference_by_name</code> to which we can simply provide a hardcoded
1131 string; <code>pretty.h</code> has an extremely handy <code>pp_commit_easy()</code> call which doesn&#8217;t
1132 require a full format object to be passed.</p></div>
1133 <div class="paragraph"><p>Add the following includes:</p></div>
1134 <div class="listingblock">
1135 <div class="content">
1136 <pre><code>#include "commit.h"
1137 #include "pretty.h"</code></pre>
1138 </div></div>
1139 <div class="paragraph"><p>Then, add the following lines within your implementation of <code>cmd_psuh()</code> near
1140 the declarations and the logic, respectively.</p></div>
1141 <div class="listingblock">
1142 <div class="content">
1143 <pre><code>        struct commit *c = NULL;
1144         struct strbuf commitline = STRBUF_INIT;
1145
1146 ...
1147
1148         c = lookup_commit_reference_by_name("origin/master");
1149
1150         if (c != NULL) {
1151                 pp_commit_easy(CMIT_FMT_ONELINE, c, &amp;commitline);
1152                 printf(_("Current commit: %s\n"), commitline.buf);
1153         }</code></pre>
1154 </div></div>
1155 <div class="paragraph"><p>The <code>struct strbuf</code> provides some safety belts to your basic <code>char*</code>, one of
1156 which is a length member to prevent buffer overruns. It needs to be initialized
1157 nicely with <code>STRBUF_INIT</code>. Keep it in mind when you need to pass around <code>char*</code>.</p></div>
1158 <div class="paragraph"><p><code>lookup_commit_reference_by_name</code> resolves the name you pass it, so you can play
1159 with the value there and see what kind of things you can come up with.</p></div>
1160 <div class="paragraph"><p><code>pp_commit_easy</code> is a convenience wrapper in <code>pretty.h</code> that takes a single
1161 format enum shorthand, rather than an entire format struct. It then
1162 pretty-prints the commit according to that shorthand. These are similar to the
1163 formats available with <code>--pretty=FOO</code> in many Git commands.</p></div>
1164 <div class="paragraph"><p>Build it and run, and if you&#8217;re using the same name in the example, you should
1165 see the subject line of the most recent commit in <code>origin/master</code> that you know
1166 about. Neat! Let&#8217;s commit that as well.</p></div>
1167 <div class="listingblock">
1168 <div class="content">
1169 <pre><code>$ git add builtin/psuh.c
1170 $ git commit -sm "psuh: display the top of origin/master"</code></pre>
1171 </div></div>
1172 </div>
1173 <div class="sect2">
1174 <h3 id="add-documentation">Adding Documentation</h3>
1175 <div class="paragraph"><p>Awesome! You&#8217;ve got a fantastic new command that you&#8217;re ready to share with the
1176 community. But hang on just a minute - this isn&#8217;t very user-friendly. Run the
1177 following:</p></div>
1178 <div class="listingblock">
1179 <div class="content">
1180 <pre><code>$ ./bin-wrappers/git help psuh</code></pre>
1181 </div></div>
1182 <div class="paragraph"><p>Your new command is undocumented! Let&#8217;s fix that.</p></div>
1183 <div class="paragraph"><p>Take a look at <code>Documentation/git-*.txt</code>. These are the manpages for the
1184 subcommands that Git knows about. You can open these up and take a look to get
1185 acquainted with the format, but then go ahead and make a new file
1186 <code>Documentation/git-psuh.txt</code>. Like with most of the documentation in the Git
1187 project, help pages are written with AsciiDoc (see CodingGuidelines, "Writing
1188 Documentation" section). Use the following template to fill out your own
1189 manpage:</p></div>
1190 <div class="listingblock">
1191 <div class="content">
1192 <pre><code>git-psuh(1)
1193 ===========
1194
1195 NAME
1196 ----
1197 git-psuh - Delight users' typo with a shy horse
1198
1199
1200 SYNOPSIS
1201 --------
1202 [verse]
1203 'git-psuh [&lt;arg&gt;...]'
1204
1205 DESCRIPTION
1206 -----------
1207 ...
1208
1209 OPTIONS[[OPTIONS]]
1210 ------------------
1211 ...
1212
1213 OUTPUT
1214 ------
1215 ...
1216
1217 GIT
1218 ---
1219 Part of the linkgit:git[1] suite</code></pre>
1220 </div></div>
1221 <div class="paragraph"><p>The most important pieces of this to note are the file header, underlined by =,
1222 the NAME section, and the SYNOPSIS, which would normally contain the grammar if
1223 your command took arguments. Try to use well-established manpage headers so your
1224 documentation is consistent with other Git and UNIX manpages; this makes life
1225 easier for your user, who can skip to the section they know contains the
1226 information they need.</p></div>
1227 <div class="admonitionblock">
1228 <table><tr>
1229 <td class="icon">
1230 <div class="title">Note</div>
1231 </td>
1232 <td class="content">Before trying to build the docs, make sure you have the package <code>asciidoc</code>
1233 installed.</td>
1234 </tr></table>
1235 </div>
1236 <div class="paragraph"><p>Now that you&#8217;ve written your manpage, you&#8217;ll need to build it explicitly. We
1237 convert your AsciiDoc to troff which is man-readable like so:</p></div>
1238 <div class="listingblock">
1239 <div class="content">
1240 <pre><code>$ make all doc
1241 $ man Documentation/git-psuh.1</code></pre>
1242 </div></div>
1243 <div class="paragraph"><p>or</p></div>
1244 <div class="listingblock">
1245 <div class="content">
1246 <pre><code>$ make -C Documentation/ git-psuh.1
1247 $ man Documentation/git-psuh.1</code></pre>
1248 </div></div>
1249 <div class="paragraph"><p>While this isn&#8217;t as satisfying as running through <code>git help</code>, you can at least
1250 check that your help page looks right.</p></div>
1251 <div class="paragraph"><p>You can also check that the documentation coverage is good (that is, the project
1252 sees that your command has been implemented as well as documented) by running
1253 <code>make check-docs</code> from the top-level.</p></div>
1254 <div class="paragraph"><p>Go ahead and commit your new documentation change.</p></div>
1255 </div>
1256 <div class="sect2">
1257 <h3 id="add-usage">Adding Usage Text</h3>
1258 <div class="paragraph"><p>Try and run <code>./bin-wrappers/git psuh -h</code>. Your command should crash at the end.
1259 That&#8217;s because <code>-h</code> is a special case which your command should handle by
1260 printing usage.</p></div>
1261 <div class="paragraph"><p>Take a look at <code>Documentation/technical/api-parse-options.txt</code>. This is a handy
1262 tool for pulling out options you need to be able to handle, and it takes a
1263 usage string.</p></div>
1264 <div class="paragraph"><p>In order to use it, we&#8217;ll need to prepare a NULL-terminated array of usage
1265 strings and a <code>builtin_psuh_options</code> array.</p></div>
1266 <div class="paragraph"><p>Add a line to <code>#include "parse-options.h"</code>.</p></div>
1267 <div class="paragraph"><p>At global scope, add your array of usage strings:</p></div>
1268 <div class="listingblock">
1269 <div class="content">
1270 <pre><code>static const char * const psuh_usage[] = {
1271         N_("git psuh [&lt;arg&gt;...]"),
1272         NULL,
1273 };</code></pre>
1274 </div></div>
1275 <div class="paragraph"><p>Then, within your <code>cmd_psuh()</code> implementation, we can declare and populate our
1276 <code>option</code> struct. Ours is pretty boring but you can add more to it if you want to
1277 explore <code>parse_options()</code> in more detail:</p></div>
1278 <div class="listingblock">
1279 <div class="content">
1280 <pre><code>        struct option options[] = {
1281                 OPT_END()
1282         };</code></pre>
1283 </div></div>
1284 <div class="paragraph"><p>Finally, before you print your args and prefix, add the call to
1285 <code>parse-options()</code>:</p></div>
1286 <div class="listingblock">
1287 <div class="content">
1288 <pre><code>        argc = parse_options(argc, argv, prefix, options, psuh_usage, 0);</code></pre>
1289 </div></div>
1290 <div class="paragraph"><p>This call will modify your <code>argv</code> parameter. It will strip the options you
1291 specified in <code>options</code> from <code>argv</code> and the locations pointed to from <code>options</code>
1292 entries will be updated. Be sure to replace your <code>argc</code> with the result from
1293 <code>parse_options()</code>, or you will be confused if you try to parse <code>argv</code> later.</p></div>
1294 <div class="paragraph"><p>It&#8217;s worth noting the special argument <code>--</code>. As you may be aware, many Unix
1295 commands use <code>--</code> to indicate "end of named parameters" - all parameters after
1296 the <code>--</code> are interpreted merely as positional arguments. (This can be handy if
1297 you want to pass as a parameter something which would usually be interpreted as
1298 a flag.) <code>parse_options()</code> will terminate parsing when it reaches <code>--</code> and give
1299 you the rest of the options afterwards, untouched.</p></div>
1300 <div class="paragraph"><p>Now that you have a usage hint, you can teach Git how to show it in the general
1301 command list shown by <code>git help git</code> or <code>git help -a</code>, which is generated from
1302 <code>command-list.txt</code>. Find the line for <em>git-pull</em> so you can add your <em>git-psuh</em>
1303 line above it in alphabetical order. Now, we can add some attributes about the
1304 command which impacts where it shows up in the aforementioned help commands. The
1305 top of <code>command-list.txt</code> shares some information about what each attribute
1306 means; in those help pages, the commands are sorted according to these
1307 attributes. <code>git psuh</code> is user-facing, or porcelain - so we will mark it as
1308 "mainporcelain". For "mainporcelain" commands, the comments at the top of
1309 <code>command-list.txt</code> indicate we can also optionally add an attribute from another
1310 list; since <code>git psuh</code> shows some information about the user&#8217;s workspace but
1311 doesn&#8217;t modify anything, let&#8217;s mark it as "info". Make sure to keep your
1312 attributes in the same style as the rest of <code>command-list.txt</code> using spaces to
1313 align and delineate them:</p></div>
1314 <div class="listingblock">
1315 <div class="content">
1316 <pre><code>git-prune-packed                        plumbingmanipulators
1317 git-psuh                                mainporcelain           info
1318 git-pull                                mainporcelain           remote
1319 git-push                                mainporcelain           remote</code></pre>
1320 </div></div>
1321 <div class="paragraph"><p>Build again. Now, when you run with <code>-h</code>, you should see your usage printed and
1322 your command terminated before anything else interesting happens. Great!</p></div>
1323 <div class="paragraph"><p>Go ahead and commit this one, too.</p></div>
1324 </div>
1325 </div>
1326 </div>
1327 <div class="sect1">
1328 <h2 id="testing">Testing</h2>
1329 <div class="sectionbody">
1330 <div class="paragraph"><p>It&#8217;s important to test your code - even for a little toy command like this one.
1331 Moreover, your patch won&#8217;t be accepted into the Git tree without tests. Your
1332 tests should:</p></div>
1333 <div class="ulist"><ul>
1334 <li>
1335 <p>
1336 Illustrate the current behavior of the feature
1337 </p>
1338 </li>
1339 <li>
1340 <p>
1341 Prove the current behavior matches the expected behavior
1342 </p>
1343 </li>
1344 <li>
1345 <p>
1346 Ensure the externally-visible behavior isn&#8217;t broken in later changes
1347 </p>
1348 </li>
1349 </ul></div>
1350 <div class="paragraph"><p>So let&#8217;s write some tests.</p></div>
1351 <div class="paragraph"><p>Related reading: <code>t/README</code></p></div>
1352 <div class="sect2">
1353 <h3 id="overview-test-structure">Overview of Testing Structure</h3>
1354 <div class="paragraph"><p>The tests in Git live in <code>t/</code> and are named with a 4-digit decimal number using
1355 the schema shown in the Naming Tests section of <code>t/README</code>.</p></div>
1356 </div>
1357 <div class="sect2">
1358 <h3 id="write-new-test">Writing Your Test</h3>
1359 <div class="paragraph"><p>Since this a toy command, let&#8217;s go ahead and name the test with t9999. However,
1360 as many of the family/subcmd combinations are full, best practice seems to be
1361 to find a command close enough to the one you&#8217;ve added and share its naming
1362 space.</p></div>
1363 <div class="paragraph"><p>Create a new file <code>t/t9999-psuh-tutorial.sh</code>. Begin with the header as so (see
1364 "Writing Tests" and "Source <em>test-lib.sh</em>" in <code>t/README</code>):</p></div>
1365 <div class="listingblock">
1366 <div class="content">
1367 <pre><code>#!/bin/sh
1368
1369 test_description='git-psuh test
1370
1371 This test runs git-psuh and makes sure it does not crash.'
1372
1373 . ./test-lib.sh</code></pre>
1374 </div></div>
1375 <div class="paragraph"><p>Tests are framed inside of a <code>test_expect_success</code> in order to output TAP
1376 formatted results. Let&#8217;s make sure that <code>git psuh</code> doesn&#8217;t exit poorly and does
1377 mention the right animal somewhere:</p></div>
1378 <div class="listingblock">
1379 <div class="content">
1380 <pre><code>test_expect_success 'runs correctly with no args and good output' '
1381         git psuh &gt;actual &amp;&amp;
1382         grep Pony actual
1383 '</code></pre>
1384 </div></div>
1385 <div class="paragraph"><p>Indicate that you&#8217;ve run everything you wanted by adding the following at the
1386 bottom of your script:</p></div>
1387 <div class="listingblock">
1388 <div class="content">
1389 <pre><code>test_done</code></pre>
1390 </div></div>
1391 <div class="paragraph"><p>Make sure you mark your test script executable:</p></div>
1392 <div class="listingblock">
1393 <div class="content">
1394 <pre><code>$ chmod +x t/t9999-psuh-tutorial.sh</code></pre>
1395 </div></div>
1396 <div class="paragraph"><p>You can get an idea of whether you created your new test script successfully
1397 by running <code>make -C t test-lint</code>, which will check for things like test number
1398 uniqueness, executable bit, and so on.</p></div>
1399 </div>
1400 <div class="sect2">
1401 <h3 id="local-test">Running Locally</h3>
1402 <div class="paragraph"><p>Let&#8217;s try and run locally:</p></div>
1403 <div class="listingblock">
1404 <div class="content">
1405 <pre><code>$ make
1406 $ cd t/ &amp;&amp; prove t9999-psuh-tutorial.sh</code></pre>
1407 </div></div>
1408 <div class="paragraph"><p>You can run the full test suite and ensure <code>git-psuh</code> didn&#8217;t break anything:</p></div>
1409 <div class="listingblock">
1410 <div class="content">
1411 <pre><code>$ cd t/
1412 $ prove -j$(nproc) --shuffle t[0-9]*.sh</code></pre>
1413 </div></div>
1414 <div class="admonitionblock">
1415 <table><tr>
1416 <td class="icon">
1417 <div class="title">Note</div>
1418 </td>
1419 <td class="content">You can also do this with <code>make test</code> or use any testing harness which can
1420 speak TAP. <code>prove</code> can run concurrently. <code>shuffle</code> randomizes the order the
1421 tests are run in, which makes them resilient against unwanted inter-test
1422 dependencies. <code>prove</code> also makes the output nicer.</td>
1423 </tr></table>
1424 </div>
1425 <div class="paragraph"><p>Go ahead and commit this change, as well.</p></div>
1426 </div>
1427 </div>
1428 </div>
1429 <div class="sect1">
1430 <h2 id="ready-to-share">Getting Ready to Share: Anatomy of a Patch Series</h2>
1431 <div class="sectionbody">
1432 <div class="paragraph"><p>You may have noticed already that the Git project performs its code reviews via
1433 emailed patches, which are then applied by the maintainer when they are ready
1434 and approved by the community. The Git project does not accept contributions from
1435 pull requests, and the patches emailed for review need to be formatted a
1436 specific way.</p></div>
1437 <div class="paragraph"><p>Before taking a look at how to convert your commits into emailed patches,
1438 let&#8217;s analyze what the end result, a "patch series", looks like. Here is an
1439 <a href="https://lore.kernel.org/git/pull.1218.git.git.1645209647.gitgitgadget@gmail.com/">example</a> of the summary view for a patch series on the web interface of
1440 the <a href="https://lore.kernel.org/git/">Git mailing list archive</a>:</p></div>
1441 <div class="listingblock">
1442 <div class="content">
1443 <pre><code>2022-02-18 18:40 [PATCH 0/3] libify reflog John Cai via GitGitGadget
1444 2022-02-18 18:40 ` [PATCH 1/3] reflog: libify delete reflog function and helpers John Cai via GitGitGadget
1445 2022-02-18 19:10   ` Ævar Arnfjörð Bjarmason [this message]
1446 2022-02-18 19:39     ` Taylor Blau
1447 2022-02-18 19:48       ` Ævar Arnfjörð Bjarmason
1448 2022-02-18 19:35   ` Taylor Blau
1449 2022-02-21  1:43     ` John Cai
1450 2022-02-21  1:50       ` Taylor Blau
1451 2022-02-23 19:50         ` John Cai
1452 2022-02-18 20:00   ` // other replies elided
1453 2022-02-18 18:40 ` [PATCH 2/3] reflog: call reflog_delete from reflog.c John Cai via GitGitGadget
1454 2022-02-18 19:15   ` Ævar Arnfjörð Bjarmason
1455 2022-02-18 20:26     ` Junio C Hamano
1456 2022-02-18 18:40 ` [PATCH 3/3] stash: call reflog_delete from reflog.c John Cai via GitGitGadget
1457 2022-02-18 19:20   ` Ævar Arnfjörð Bjarmason
1458 2022-02-19  0:21     ` Taylor Blau
1459 2022-02-22  2:36     ` John Cai
1460 2022-02-22 10:51       ` Ævar Arnfjörð Bjarmason
1461 2022-02-18 19:29 ` [PATCH 0/3] libify reflog Ævar Arnfjörð Bjarmason
1462 2022-02-22 18:30 ` [PATCH v2 0/3] libify reflog John Cai via GitGitGadget
1463 2022-02-22 18:30   ` [PATCH v2 1/3] stash: add test to ensure reflog --rewrite --updatref behavior John Cai via GitGitGadget
1464 2022-02-23  8:54     ` Ævar Arnfjörð Bjarmason
1465 2022-02-23 21:27       ` Junio C Hamano
1466 // continued</code></pre>
1467 </div></div>
1468 <div class="paragraph"><p>We can note a few things:</p></div>
1469 <div class="ulist"><ul>
1470 <li>
1471 <p>
1472 Each commit is sent as a separate email, with the commit message title as
1473   subject, prefixed with "[PATCH <em>i</em>/<em>n</em>]" for the <em>i</em>-th commit of an
1474   <em>n</em>-commit series.
1475 </p>
1476 </li>
1477 <li>
1478 <p>
1479 Each patch is sent as a reply to an introductory email called the <em>cover
1480   letter</em> of the series, prefixed "[PATCH 0/<em>n</em>]".
1481 </p>
1482 </li>
1483 <li>
1484 <p>
1485 Subsequent iterations of the patch series are labelled "PATCH v2", "PATCH
1486   v3", etc. in place of "PATCH". For example, "[PATCH v2 1/3]" would be the first of
1487   three patches in the second iteration. Each iteration is sent with a new cover
1488   letter (like "[PATCH v2 0/3]" above), itself a reply to the cover letter of the
1489   previous iteration (more on that below).
1490 </p>
1491 </li>
1492 </ul></div>
1493 <div class="admonitionblock">
1494 <table><tr>
1495 <td class="icon">
1496 <div class="title">Note</div>
1497 </td>
1498 <td class="content">A single-patch topic is sent with "[PATCH]", "[PATCH v2]", etc. without
1499 <em>i</em>/<em>n</em> numbering (in the above thread overview, no single-patch topic appears,
1500 though).</td>
1501 </tr></table>
1502 </div>
1503 <div class="sect2">
1504 <h3 id="cover-letter">The cover letter</h3>
1505 <div class="paragraph"><p>In addition to an email per patch, the Git community also expects your patches
1506 to come with a cover letter. This is an important component of change
1507 submission as it explains to the community from a high level what you&#8217;re trying
1508 to do, and why, in a way that&#8217;s more apparent than just looking at your
1509 patches.</p></div>
1510 <div class="paragraph"><p>The title of your cover letter should be something which succinctly covers the
1511 purpose of your entire topic branch. It&#8217;s often in the imperative mood, just
1512 like our commit message titles. Here is how we&#8217;ll title our series:</p></div>
1513 <div class="paragraph"><p>---
1514 Add the <em>psuh</em> command
1515 ---</p></div>
1516 <div class="paragraph"><p>The body of the cover letter is used to give additional context to reviewers.
1517 Be sure to explain anything your patches don&#8217;t make clear on their own, but
1518 remember that since the cover letter is not recorded in the commit history,
1519 anything that might be useful to future readers of the repository&#8217;s history
1520 should also be in your commit messages.</p></div>
1521 <div class="paragraph"><p>Here&#8217;s an example body for <code>psuh</code>:</p></div>
1522 <div class="listingblock">
1523 <div class="content">
1524 <pre><code>Our internal metrics indicate widespread interest in the command
1525 git-psuh - that is, many users are trying to use it, but finding it is
1526 unavailable, using some unknown workaround instead.
1527
1528 The following handful of patches add the psuh command and implement some
1529 handy features on top of it.
1530
1531 This patchset is part of the MyFirstContribution tutorial and should not
1532 be merged.</code></pre>
1533 </div></div>
1534 <div class="paragraph"><p>At this point the tutorial diverges, in order to demonstrate two
1535 different methods of formatting your patchset and getting it reviewed.</p></div>
1536 <div class="paragraph"><p>The first method to be covered is GitGitGadget, which is useful for those
1537 already familiar with GitHub&#8217;s common pull request workflow. This method
1538 requires a GitHub account.</p></div>
1539 <div class="paragraph"><p>The second method to be covered is <code>git send-email</code>, which can give slightly
1540 more fine-grained control over the emails to be sent. This method requires some
1541 setup which can change depending on your system and will not be covered in this
1542 tutorial.</p></div>
1543 <div class="paragraph"><p>Regardless of which method you choose, your engagement with reviewers will be
1544 the same; the review process will be covered after the sections on GitGitGadget
1545 and <code>git send-email</code>.</p></div>
1546 </div>
1547 </div>
1548 </div>
1549 <div class="sect1">
1550 <h2 id="howto-ggg">Sending Patches via GitGitGadget</h2>
1551 <div class="sectionbody">
1552 <div class="paragraph"><p>One option for sending patches is to follow a typical pull request workflow and
1553 send your patches out via GitGitGadget. GitGitGadget is a tool created by
1554 Johannes Schindelin to make life as a Git contributor easier for those used to
1555 the GitHub PR workflow. It allows contributors to open pull requests against its
1556 mirror of the Git project, and does some magic to turn the PR into a set of
1557 emails and send them out for you. It also runs the Git continuous integration
1558 suite for you. It&#8217;s documented at <a href="http://gitgitgadget.github.io">http://gitgitgadget.github.io</a>.</p></div>
1559 <div class="sect2">
1560 <h3 id="create-fork">Forking <code>git/git</code> on GitHub</h3>
1561 <div class="paragraph"><p>Before you can send your patch off to be reviewed using GitGitGadget, you will
1562 need to fork the Git project and upload your changes. First thing - make sure
1563 you have a GitHub account.</p></div>
1564 <div class="paragraph"><p>Head to the <a href="https://github.com/git/git">GitHub mirror</a> and look for the Fork
1565 button. Place your fork wherever you deem appropriate and create it.</p></div>
1566 </div>
1567 <div class="sect2">
1568 <h3 id="upload-to-fork">Uploading to Your Own Fork</h3>
1569 <div class="paragraph"><p>To upload your branch to your own fork, you&#8217;ll need to add the new fork as a
1570 remote. You can use <code>git remote -v</code> to show the remotes you have added already.
1571 From your new fork&#8217;s page on GitHub, you can press "Clone or download" to get
1572 the URL; then you need to run the following to add, replacing your own URL and
1573 remote name for the examples provided:</p></div>
1574 <div class="listingblock">
1575 <div class="content">
1576 <pre><code>$ git remote add remotename git@github.com:remotename/git.git</code></pre>
1577 </div></div>
1578 <div class="paragraph"><p>or to use the HTTPS URL:</p></div>
1579 <div class="listingblock">
1580 <div class="content">
1581 <pre><code>$ git remote add remotename https://github.com/remotename/git/.git</code></pre>
1582 </div></div>
1583 <div class="paragraph"><p>Run <code>git remote -v</code> again and you should see the new remote showing up.
1584 <code>git fetch remotename</code> (with the real name of your remote replaced) in order to
1585 get ready to push.</p></div>
1586 <div class="paragraph"><p>Next, double-check that you&#8217;ve been doing all your development in a new branch
1587 by running <code>git branch</code>. If you didn&#8217;t, now is a good time to move your new
1588 commits to their own branch.</p></div>
1589 <div class="paragraph"><p>As mentioned briefly at the beginning of this document, we are basing our work
1590 on <code>master</code>, so go ahead and update as shown below, or using your preferred
1591 workflow.</p></div>
1592 <div class="listingblock">
1593 <div class="content">
1594 <pre><code>$ git checkout master
1595 $ git pull -r
1596 $ git rebase master psuh</code></pre>
1597 </div></div>
1598 <div class="paragraph"><p>Finally, you&#8217;re ready to push your new topic branch! (Due to our branch and
1599 command name choices, be careful when you type the command below.)</p></div>
1600 <div class="listingblock">
1601 <div class="content">
1602 <pre><code>$ git push remotename psuh</code></pre>
1603 </div></div>
1604 <div class="paragraph"><p>Now you should be able to go and check out your newly created branch on GitHub.</p></div>
1605 </div>
1606 <div class="sect2">
1607 <h3 id="send-pr-ggg">Sending a PR to GitGitGadget</h3>
1608 <div class="paragraph"><p>In order to have your code tested and formatted for review, you need to start by
1609 opening a Pull Request against <code>gitgitgadget/git</code>. Head to
1610 <a href="https://github.com/gitgitgadget/git">https://github.com/gitgitgadget/git</a> and open a PR either with the "New pull
1611 request" button or the convenient "Compare &amp; pull request" button that may
1612 appear with the name of your newly pushed branch.</p></div>
1613 <div class="paragraph"><p>Review the PR&#8217;s title and description, as they&#8217;re used by GitGitGadget
1614 respectively as the subject and body of the cover letter for your change. Refer
1615 to <a href="#cover-letter">"The cover letter"</a> above for advice on how to title your
1616 submission and what content to include in the description.</p></div>
1617 <div class="admonitionblock">
1618 <table><tr>
1619 <td class="icon">
1620 <div class="title">Note</div>
1621 </td>
1622 <td class="content">For single-patch contributions, your commit message should already be
1623 meaningful and explain at a high level the purpose (what is happening and why)
1624 of your patch, so you usually do not need any additional context. In that case,
1625 remove the PR description that GitHub automatically generates from your commit
1626 message (your PR description should be empty). If you do need to supply even
1627 more context, you can do so in that space and it will be appended to the email
1628 that GitGitGadget will send, between the three-dash line and the diffstat
1629 (see <a href="#single-patch">Bonus Chapter: One-Patch Changes</a> for how this looks once
1630 submitted).</td>
1631 </tr></table>
1632 </div>
1633 <div class="paragraph"><p>When you&#8217;re happy, submit your pull request.</p></div>
1634 </div>
1635 <div class="sect2">
1636 <h3 id="run-ci-ggg">Running CI and Getting Ready to Send</h3>
1637 <div class="paragraph"><p>If it&#8217;s your first time using GitGitGadget (which is likely, as you&#8217;re using
1638 this tutorial) then someone will need to give you permission to use the tool.
1639 As mentioned in the GitGitGadget documentation, you just need someone who
1640 already uses it to comment on your PR with <code>/allow &lt;username&gt;</code>. GitGitGadget
1641 will automatically run your PRs through the CI even without the permission given
1642 but you will not be able to <code>/submit</code> your changes until someone allows you to
1643 use the tool.</p></div>
1644 <div class="admonitionblock">
1645 <table><tr>
1646 <td class="icon">
1647 <div class="title">Note</div>
1648 </td>
1649 <td class="content">You can typically find someone who can <code>/allow</code> you on GitGitGadget by
1650 either examining recent pull requests where someone has been granted <code>/allow</code>
1651 (<a href="https://github.com/gitgitgadget/git/pulls?utf8=%E2%9C%93&amp;q=is%3Apr+is%3Aopen+%22%2Fallow%22">Search:
1652 is:pr is:open "/allow"</a>), in which case both the author and the person who
1653 granted the <code>/allow</code> can now <code>/allow</code> you, or by inquiring on the
1654 <a href="https://web.libera.chat/#git-devel">#git-devel</a> IRC channel on Libera Chat
1655 linking your pull request and asking for someone to <code>/allow</code> you.</td>
1656 </tr></table>
1657 </div>
1658 <div class="paragraph"><p>If the CI fails, you can update your changes with <code>git rebase -i</code> and push your
1659 branch again:</p></div>
1660 <div class="listingblock">
1661 <div class="content">
1662 <pre><code>$ git push -f remotename psuh</code></pre>
1663 </div></div>
1664 <div class="paragraph"><p>In fact, you should continue to make changes this way up until the point when
1665 your patch is accepted into <code>next</code>.</p></div>
1666 </div>
1667 <div class="sect2">
1668 <h3 id="send-mail-ggg">Sending Your Patches</h3>
1669 <div class="paragraph"><p>Now that your CI is passing and someone has granted you permission to use
1670 GitGitGadget with the <code>/allow</code> command, sending out for review is as simple as
1671 commenting on your PR with <code>/submit</code>.</p></div>
1672 </div>
1673 <div class="sect2">
1674 <h3 id="responding-ggg">Updating With Comments</h3>
1675 <div class="paragraph"><p>Skip ahead to <a href="#reviewing">Responding to Reviews</a> for information on how to
1676 reply to review comments you will receive on the mailing list.</p></div>
1677 <div class="paragraph"><p>Once you have your branch again in the shape you want following all review
1678 comments, you can submit again:</p></div>
1679 <div class="listingblock">
1680 <div class="content">
1681 <pre><code>$ git push -f remotename psuh</code></pre>
1682 </div></div>
1683 <div class="paragraph"><p>Next, go look at your pull request against GitGitGadget; you should see the CI
1684 has been kicked off again. Now while the CI is running is a good time for you
1685 to modify your description at the top of the pull request thread; it will be
1686 used again as the cover letter. You should use this space to describe what
1687 has changed since your previous version, so that your reviewers have some idea
1688 of what they&#8217;re looking at. When the CI is done running, you can comment once
1689 more with <code>/submit</code> - GitGitGadget will automatically add a v2 mark to your
1690 changes.</p></div>
1691 </div>
1692 </div>
1693 </div>
1694 <div class="sect1">
1695 <h2 id="howto-git-send-email">Sending Patches with <code>git send-email</code></h2>
1696 <div class="sectionbody">
1697 <div class="paragraph"><p>If you don&#8217;t want to use GitGitGadget, you can also use Git itself to mail your
1698 patches. Some benefits of using Git this way include finer grained control of
1699 subject line (for example, being able to use the tag [RFC PATCH] in the subject)
1700 and being able to send a &#8220;dry run&#8221; mail to yourself to ensure it all looks
1701 good before going out to the list.</p></div>
1702 <div class="sect2">
1703 <h3 id="setup-git-send-email">Prerequisite: Setting Up <code>git send-email</code></h3>
1704 <div class="paragraph"><p>Configuration for <code>send-email</code> can vary based on your operating system and email
1705 provider, and so will not be covered in this tutorial, beyond stating that in
1706 many distributions of Linux, <code>git-send-email</code> is not packaged alongside the
1707 typical <code>git</code> install. You may need to install this additional package; there
1708 are a number of resources online to help you do so. You will also need to
1709 determine the right way to configure it to use your SMTP server; again, as this
1710 configuration can change significantly based on your system and email setup, it
1711 is out of scope for the context of this tutorial.</p></div>
1712 </div>
1713 <div class="sect2">
1714 <h3 id="format-patch">Preparing Initial Patchset</h3>
1715 <div class="paragraph"><p>Sending emails with Git is a two-part process; before you can prepare the emails
1716 themselves, you&#8217;ll need to prepare the patches. Luckily, this is pretty simple:</p></div>
1717 <div class="listingblock">
1718 <div class="content">
1719 <pre><code>$ git format-patch --cover-letter -o psuh/ --base=auto psuh@{u}..psuh</code></pre>
1720 </div></div>
1721 <div class="olist arabic"><ol class="arabic">
1722 <li>
1723 <p>
1724 The <code>--cover-letter</code> option tells <code>format-patch</code> to create a
1725    cover letter template for you. You will need to fill in the
1726    template before you&#8217;re ready to send - but for now, the template
1727    will be next to your other patches.
1728 </p>
1729 </li>
1730 <li>
1731 <p>
1732 The <code>-o psuh/</code> option tells <code>format-patch</code> to place the patch
1733    files into a directory. This is useful because <code>git send-email</code>
1734    can take a directory and send out all the patches from there.
1735 </p>
1736 </li>
1737 <li>
1738 <p>
1739 The <code>--base=auto</code> option tells the command to record the "base
1740    commit", on which the recipient is expected to apply the patch
1741    series.  The <code>auto</code> value will cause <code>format-patch</code> to compute
1742    the base commit automatically, which is the merge base of tip
1743    commit of the remote-tracking branch and the specified revision
1744    range.
1745 </p>
1746 </li>
1747 <li>
1748 <p>
1749 The <code>psuh@{u}..psuh</code> option tells <code>format-patch</code> to generate
1750    patches for the commits you created on the <code>psuh</code> branch since it
1751    forked from its upstream (which is <code>origin/master</code> if you
1752    followed the example in the "Set up your workspace" section).  If
1753    you are already on the <code>psuh</code> branch, you can just say <code>@{u}</code>,
1754    which means "commits on the current branch since it forked from
1755    its upstream", which is the same thing.
1756 </p>
1757 </li>
1758 </ol></div>
1759 <div class="paragraph"><p>The command will make one patch file per commit. After you
1760 run, you can go have a look at each of the patches with your favorite text
1761 editor and make sure everything looks alright; however, it&#8217;s not recommended to
1762 make code fixups via the patch file. It&#8217;s a better idea to make the change the
1763 normal way using <code>git rebase -i</code> or by adding a new commit than by modifying a
1764 patch.</p></div>
1765 <div class="admonitionblock">
1766 <table><tr>
1767 <td class="icon">
1768 <div class="title">Note</div>
1769 </td>
1770 <td class="content">Optionally, you can also use the <code>--rfc</code> flag to prefix your patch subject
1771 with &#8220;[RFC PATCH]&#8221; instead of &#8220;[PATCH]&#8221;. RFC stands for &#8220;request for
1772 comments&#8221; and indicates that while your code isn&#8217;t quite ready for submission,
1773 you&#8217;d like to begin the code review process. This can also be used when your
1774 patch is a proposal, but you aren&#8217;t sure whether the community wants to solve
1775 the problem with that approach or not - to conduct a sort of design review. You
1776 may also see on the list patches marked &#8220;WIP&#8221; - this means they are incomplete
1777 but want reviewers to look at what they have so far. You can add this flag with
1778 <code>--subject-prefix=WIP</code>.</td>
1779 </tr></table>
1780 </div>
1781 <div class="paragraph"><p>Check and make sure that your patches and cover letter template exist in the
1782 directory you specified - you&#8217;re nearly ready to send out your review!</p></div>
1783 </div>
1784 <div class="sect2">
1785 <h3 id="preparing-cover-letter">Preparing Email</h3>
1786 <div class="paragraph"><p>Since you invoked <code>format-patch</code> with <code>--cover-letter</code>, you&#8217;ve already got a
1787 cover letter template ready. Open it up in your favorite editor.</p></div>
1788 <div class="paragraph"><p>You should see a number of headers present already. Check that your <code>From:</code>
1789 header is correct. Then modify your <code>Subject:</code> (see <a href="#cover-letter">above</a> for
1790 how to choose good title for your patch series):</p></div>
1791 <div class="listingblock">
1792 <div class="content">
1793 <pre><code>Subject: [PATCH 0/7] Add the 'psuh' command</code></pre>
1794 </div></div>
1795 <div class="paragraph"><p>Make sure you retain the &#8220;[PATCH 0/X]&#8221; part; that&#8217;s what indicates to the Git
1796 community that this email is the beginning of a patch series, and many
1797 reviewers filter their email for this type of flag.</p></div>
1798 <div class="paragraph"><p>You&#8217;ll need to add some extra parameters when you invoke <code>git send-email</code> to add
1799 the cover letter.</p></div>
1800 <div class="paragraph"><p>Next you&#8217;ll have to fill out the body of your cover letter. Again, see
1801 <a href="#cover-letter">above</a> for what content to include.</p></div>
1802 <div class="paragraph"><p>The template created by <code>git format-patch --cover-letter</code> includes a diffstat.
1803 This gives reviewers a summary of what they&#8217;re in for when reviewing your topic.
1804 The one generated for <code>psuh</code> from the sample implementation looks like this:</p></div>
1805 <div class="listingblock">
1806 <div class="content">
1807 <pre><code> Documentation/git-psuh.txt | 40 +++++++++++++++++++++
1808  Makefile                   |  1 +
1809  builtin.h                  |  1 +
1810  builtin/psuh.c             | 73 ++++++++++++++++++++++++++++++++++++++
1811  git.c                      |  1 +
1812  t/t9999-psuh-tutorial.sh   | 12 +++++++
1813  6 files changed, 128 insertions(+)
1814  create mode 100644 Documentation/git-psuh.txt
1815  create mode 100644 builtin/psuh.c
1816  create mode 100755 t/t9999-psuh-tutorial.sh</code></pre>
1817 </div></div>
1818 <div class="paragraph"><p>Finally, the letter will include the version of Git used to generate the
1819 patches. You can leave that string alone.</p></div>
1820 </div>
1821 <div class="sect2">
1822 <h3 id="sending-git-send-email">Sending Email</h3>
1823 <div class="paragraph"><p>At this point you should have a directory <code>psuh/</code> which is filled with your
1824 patches and a cover letter. Time to mail it out! You can send it like this:</p></div>
1825 <div class="listingblock">
1826 <div class="content">
1827 <pre><code>$ git send-email --to=target@example.com psuh/*.patch</code></pre>
1828 </div></div>
1829 <div class="admonitionblock">
1830 <table><tr>
1831 <td class="icon">
1832 <div class="title">Note</div>
1833 </td>
1834 <td class="content">Check <code>git help send-email</code> for some other options which you may find
1835 valuable, such as changing the Reply-to address or adding more CC and BCC lines.</td>
1836 </tr></table>
1837 </div>
1838 <div class="admonitionblock">
1839 <table><tr>
1840 <td class="icon">
1841 <div class="title">Note</div>
1842 </td>
1843 <td class="content">When you are sending a real patch, it will go to <a href="mailto:git@vger.kernel.org">git@vger.kernel.org</a> - but
1844 please don&#8217;t send your patchset from the tutorial to the real mailing list! For
1845 now, you can send it to yourself, to make sure you understand how it will look.</td>
1846 </tr></table>
1847 </div>
1848 <div class="paragraph"><p>After you run the command above, you will be presented with an interactive
1849 prompt for each patch that&#8217;s about to go out. This gives you one last chance to
1850 edit or quit sending something (but again, don&#8217;t edit code this way). Once you
1851 press <code>y</code> or <code>a</code> at these prompts your emails will be sent! Congratulations!</p></div>
1852 <div class="paragraph"><p>Awesome, now the community will drop everything and review your changes. (Just
1853 kidding - be patient!)</p></div>
1854 </div>
1855 <div class="sect2">
1856 <h3 id="v2-git-send-email">Sending v2</h3>
1857 <div class="paragraph"><p>This section will focus on how to send a v2 of your patchset. To learn what
1858 should go into v2, skip ahead to <a href="#reviewing">Responding to Reviews</a> for
1859 information on how to handle comments from reviewers.</p></div>
1860 <div class="paragraph"><p>We&#8217;ll reuse our <code>psuh</code> topic branch for v2. Before we make any changes, we&#8217;ll
1861 mark the tip of our v1 branch for easy reference:</p></div>
1862 <div class="listingblock">
1863 <div class="content">
1864 <pre><code>$ git checkout psuh
1865 $ git branch psuh-v1</code></pre>
1866 </div></div>
1867 <div class="paragraph"><p>Refine your patch series by using <code>git rebase -i</code> to adjust commits based upon
1868 reviewer comments. Once the patch series is ready for submission, generate your
1869 patches again, but with some new flags:</p></div>
1870 <div class="listingblock">
1871 <div class="content">
1872 <pre><code>$ git format-patch -v2 --cover-letter -o psuh/ --range-diff master..psuh-v1 master..</code></pre>
1873 </div></div>
1874 <div class="paragraph"><p>The <code>--range-diff master..psuh-v1</code> parameter tells <code>format-patch</code> to include a
1875 range-diff between <code>psuh-v1</code> and <code>psuh</code> in the cover letter (see
1876 <a href="git-range-diff.html">git-range-diff(1)</a>). This helps tell reviewers about the differences
1877 between your v1 and v2 patches.</p></div>
1878 <div class="paragraph"><p>The <code>-v2</code> parameter tells <code>format-patch</code> to output your patches
1879 as version "2". For instance, you may notice that your v2 patches are
1880 all named like <code>v2-000n-my-commit-subject.patch</code>. <code>-v2</code> will also format
1881 your patches by prefixing them with "[PATCH v2]" instead of "[PATCH]",
1882 and your range-diff will be prefaced with "Range-diff against v1".</p></div>
1883 <div class="paragraph"><p>After you run this command, <code>format-patch</code> will output the patches to the <code>psuh/</code>
1884 directory, alongside the v1 patches. Using a single directory makes it easy to
1885 refer to the old v1 patches while proofreading the v2 patches, but you will need
1886 to be careful to send out only the v2 patches. We will use a pattern like
1887 "psuh/v2-<strong>.patch" (not "psuh/</strong>.patch", which would match v1 and v2 patches).</p></div>
1888 <div class="paragraph"><p>Edit your cover letter again. Now is a good time to mention what&#8217;s different
1889 between your last version and now, if it&#8217;s something significant. You do not
1890 need the exact same body in your second cover letter; focus on explaining to
1891 reviewers the changes you&#8217;ve made that may not be as visible.</p></div>
1892 <div class="paragraph"><p>You will also need to go and find the Message-Id of your previous cover letter.
1893 You can either note it when you send the first series, from the output of <code>git
1894 send-email</code>, or you can look it up on the
1895 <a href="https://lore.kernel.org/git">mailing list</a>. Find your cover letter in the
1896 archives, click on it, then click "permalink" or "raw" to reveal the Message-Id
1897 header. It should match:</p></div>
1898 <div class="listingblock">
1899 <div class="content">
1900 <pre><code>Message-Id: &lt;foo.12345.author@example.com&gt;</code></pre>
1901 </div></div>
1902 <div class="paragraph"><p>Your Message-Id is <code>&lt;foo.12345.author@example.com&gt;</code>. This example will be used
1903 below as well; make sure to replace it with the correct Message-Id for your
1904 <strong>previous cover letter</strong> - that is, if you&#8217;re sending v2, use the Message-Id
1905 from v1; if you&#8217;re sending v3, use the Message-Id from v2.</p></div>
1906 <div class="paragraph"><p>While you&#8217;re looking at the email, you should also note who is CC&#8217;d, as it&#8217;s
1907 common practice in the mailing list to keep all CCs on a thread. You can add
1908 these CC lines directly to your cover letter with a line like so in the header
1909 (before the Subject line):</p></div>
1910 <div class="listingblock">
1911 <div class="content">
1912 <pre><code>CC: author@example.com, Othe R &lt;other@example.com&gt;</code></pre>
1913 </div></div>
1914 <div class="paragraph"><p>Now send the emails again, paying close attention to which messages you pass in
1915 to the command:</p></div>
1916 <div class="listingblock">
1917 <div class="content">
1918 <pre><code>$ git send-email --to=target@example.com
1919                  --in-reply-to="&lt;foo.12345.author@example.com&gt;"
1920                  psuh/v2-*.patch</code></pre>
1921 </div></div>
1922 </div>
1923 <div class="sect2">
1924 <h3 id="single-patch">Bonus Chapter: One-Patch Changes</h3>
1925 <div class="paragraph"><p>In some cases, your very small change may consist of only one patch. When that
1926 happens, you only need to send one email. Your commit message should already be
1927 meaningful and explain at a high level the purpose (what is happening and why)
1928 of your patch, but if you need to supply even more context, you can do so below
1929 the <code>---</code> in your patch. Take the example below, which was generated with <code>git
1930 format-patch</code> on a single commit, and then edited to add the content between
1931 the <code>---</code> and the diffstat.</p></div>
1932 <div class="listingblock">
1933 <div class="content">
1934 <pre><code>From 1345bbb3f7ac74abde040c12e737204689a72723 Mon Sep 17 00:00:00 2001
1935 From: A U Thor &lt;author@example.com&gt;
1936 Date: Thu, 18 Apr 2019 15:11:02 -0700
1937 Subject: [PATCH] README: change the grammar
1938
1939 I think it looks better this way. This part of the commit message will
1940 end up in the commit-log.
1941
1942 Signed-off-by: A U Thor &lt;author@example.com&gt;
1943 ---
1944 Let's have a wild discussion about grammar on the mailing list. This
1945 part of my email will never end up in the commit log. Here is where I
1946 can add additional context to the mailing list about my intent, outside
1947 of the context of the commit log. This section was added after `git
1948 format-patch` was run, by editing the patch file in a text editor.
1949
1950  README.md | 2 +-
1951  1 file changed, 1 insertion(+), 1 deletion(-)
1952
1953 diff --git a/README.md b/README.md
1954 index 88f126184c..38da593a60 100644
1955 --- a/README.md
1956 +++ b/README.md
1957 @@ -3,7 +3,7 @@
1958  Git - fast, scalable, distributed revision control system
1959  =========================================================
1960
1961 -Git is a fast, scalable, distributed revision control system with an
1962 +Git is a fast, scalable, and distributed revision control system with an
1963  unusually rich command set that provides both high-level operations
1964  and full access to internals.
1965
1966 --
1967 2.21.0.392.gf8f6787159e-goog</code></pre>
1968 </div></div>
1969 </div>
1970 </div>
1971 </div>
1972 <div class="sect1">
1973 <h2 id="now-what">My Patch Got Emailed - Now What?</h2>
1974 <div class="sectionbody">
1975 <div class="sect2">
1976 <h3 id="reviewing">Responding to Reviews</h3>
1977 <div class="paragraph"><p>After a few days, you will hopefully receive a reply to your patchset with some
1978 comments. Woohoo! Now you can get back to work.</p></div>
1979 <div class="paragraph"><p>It&#8217;s good manners to reply to each comment, notifying the reviewer that you have
1980 made the change suggested, feel the original is better, or that the comment
1981 inspired you to do something a new way which is superior to both the original
1982 and the suggested change. This way reviewers don&#8217;t need to inspect your v2 to
1983 figure out whether you implemented their comment or not.</p></div>
1984 <div class="paragraph"><p>Reviewers may ask you about what you wrote in the patchset, either in
1985 the proposed commit log message or in the changes themselves.  You
1986 should answer these questions in your response messages, but often the
1987 reason why reviewers asked these questions to understand what you meant
1988 to write is because your patchset needed clarification to be understood.</p></div>
1989 <div class="paragraph"><p>Do not be satisfied by just answering their questions in your response
1990 and hear them say that they now understand what you wanted to say.
1991 Update your patches to clarify the points reviewers had trouble with,
1992 and prepare your v2; the words you used to explain your v1 to answer
1993 reviewers' questions may be useful thing to use.  Your goal is to make
1994 your v2 clear enough so that it becomes unnecessary for you to give the
1995 same explanation to the next person who reads it.</p></div>
1996 <div class="paragraph"><p>If you are going to push back on a comment, be polite and explain why you feel
1997 your original is better; be prepared that the reviewer may still disagree with
1998 you, and the rest of the community may weigh in on one side or the other. As
1999 with all code reviews, it&#8217;s important to keep an open mind to doing something a
2000 different way than you originally planned; other reviewers have a different
2001 perspective on the project than you do, and may be thinking of a valid side
2002 effect which had not occurred to you. It is always okay to ask for clarification
2003 if you aren&#8217;t sure why a change was suggested, or what the reviewer is asking
2004 you to do.</p></div>
2005 <div class="paragraph"><p>Make sure your email client has a plaintext email mode and it is turned on; the
2006 Git list rejects HTML email. Please also follow the mailing list etiquette
2007 outlined in the
2008 <a href="https://kernel.googlesource.com/pub/scm/git/git/+/todo/MaintNotes">Maintainer&#8217;s
2009 Note</a>, which are similar to etiquette rules in most open source communities
2010 surrounding bottom-posting and inline replies.</p></div>
2011 <div class="paragraph"><p>When you&#8217;re making changes to your code, it is cleanest - that is, the resulting
2012 commits are easiest to look at - if you use <code>git rebase -i</code> (interactive
2013 rebase). Take a look at this
2014 <a href="https://www.oreilly.com/library/view/git-pocket-guide/9781449327507/ch10.html">overview</a>
2015 from O&#8217;Reilly. The general idea is to modify each commit which requires changes;
2016 this way, instead of having a patch A with a mistake, a patch B which was fine
2017 and required no upstream reviews in v1, and a patch C which fixes patch A for
2018 v2, you can just ship a v2 with a correct patch A and correct patch B. This is
2019 changing history, but since it&#8217;s local history which you haven&#8217;t shared with
2020 anyone, that is okay for now! (Later, it may not make sense to do this; take a
2021 look at the section below this one for some context.)</p></div>
2022 </div>
2023 <div class="sect2">
2024 <h3 id="after-approval">After Review Approval</h3>
2025 <div class="paragraph"><p>The Git project has four integration branches: <code>seen</code>, <code>next</code>, <code>master</code>, and
2026 <code>maint</code>. Your change will be placed into <code>seen</code> fairly early on by the maintainer
2027 while it is still in the review process; from there, when it is ready for wider
2028 testing, it will be merged into <code>next</code>. Plenty of early testers use <code>next</code> and
2029 may report issues. Eventually, changes in <code>next</code> will make it to <code>master</code>,
2030 which is typically considered stable. Finally, when a new release is cut,
2031 <code>maint</code> is used to base bugfixes onto. As mentioned at the beginning of this
2032 document, you can read <code>Documents/SubmittingPatches</code> for some more info about
2033 the use of the various integration branches.</p></div>
2034 <div class="paragraph"><p>Back to now: your code has been lauded by the upstream reviewers. It is perfect.
2035 It is ready to be accepted. You don&#8217;t need to do anything else; the maintainer
2036 will merge your topic branch to <code>next</code> and life is good.</p></div>
2037 <div class="paragraph"><p>However, if you discover it isn&#8217;t so perfect after this point, you may need to
2038 take some special steps depending on where you are in the process.</p></div>
2039 <div class="paragraph"><p>If the maintainer has announced in the "What&#8217;s cooking in git.git" email that
2040 your topic is marked for <code>next</code> - that is, that they plan to merge it to <code>next</code>
2041 but have not yet done so - you should send an email asking the maintainer to
2042 wait a little longer: "I&#8217;ve sent v4 of my series and you marked it for <code>next</code>,
2043 but I need to change this and that - please wait for v5 before you merge it."</p></div>
2044 <div class="paragraph"><p>If the topic has already been merged to <code>next</code>, rather than modifying your
2045 patches with <code>git rebase -i</code>, you should make further changes incrementally -
2046 that is, with another commit, based on top of the maintainer&#8217;s topic branch as
2047 detailed in <a href="https://github.com/gitster/git">https://github.com/gitster/git</a>. Your work is still in the same topic
2048 but is now incremental, rather than a wholesale rewrite of the topic branch.</p></div>
2049 <div class="paragraph"><p>The topic branches in the maintainer&#8217;s GitHub are mirrored in GitGitGadget, so
2050 if you&#8217;re sending your reviews out that way, you should be sure to open your PR
2051 against the appropriate GitGitGadget/Git branch.</p></div>
2052 <div class="paragraph"><p>If you&#8217;re using <code>git send-email</code>, you can use it the same way as before, but you
2053 should generate your diffs from <code>&lt;topic&gt;..&lt;mybranch&gt;</code> and base your work on
2054 <code>&lt;topic&gt;</code> instead of <code>master</code>.</p></div>
2055 </div>
2056 </div>
2057 </div>
2058 </div>
2059 <div id="footnotes"><hr /></div>
2060 <div id="footer">
2061 <div id="footer-text">
2062 Last updated
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