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The Git workflow steps will largely remain unexplained.</p></div> +</div> +<div class="sect2"> +<h3 id="related-reading">Related Reading</h3> +<div class="paragraph"><p>This tutorial aims to summarize the following documents, but the reader may find +useful additional context:</p></div> +<div class="ulist"><ul> +<li> +<p> +<code>Documentation/SubmittingPatches</code> +</p> +</li> +<li> +<p> +<code>Documentation/howto/new-command.txt</code> +</p> +</li> +</ul></div> +</div> +</div> +</div> +<div class="sect1"> +<h2 id="getting-started">Getting Started</h2> +<div class="sectionbody"> +<div class="sect2"> +<h3 id="cloning">Clone the Git Repository</h3> +<div class="paragraph"><p>Git is mirrored in a number of locations. Clone the repository from one of them; +<a href="https://git-scm.com/downloads">https://git-scm.com/downloads</a> suggests one of the best places to clone from is +the mirror on GitHub.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git clone https://github.com/git/git git +$ cd git</code></pre> +</div></div> +</div> +<div class="sect2"> +<h3 id="identify-problem">Identify Problem to Solve</h3> +<div class="paragraph"><p>In this tutorial, we will add a new command, <code>git psuh</code>, short for “Pony Saying +‘Um, Hello”’ - a feature which has gone unimplemented despite a high frequency +of invocation during users' typical daily workflow.</p></div> +<div class="paragraph"><p>(We’ve seen some other effort in this space with the implementation of popular +commands such as <code>sl</code>.)</p></div> +</div> +<div class="sect2"> +<h3 id="setup-workspace">Set Up Your Workspace</h3> +<div class="paragraph"><p>Let’s start by making a development branch to work on our changes. Per +<code>Documentation/SubmittingPatches</code>, since a brand new command is a new feature, +it’s fine to base your work on <code>master</code>. However, in the future for bugfixes, +etc., you should check that document and base it on the appropriate branch.</p></div> +<div class="paragraph"><p>For the purposes of this document, we will base all our work on the <code>master</code> +branch of the upstream project. Create the <code>psuh</code> branch you will use for +development like so:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git checkout -b psuh origin/master</code></pre> +</div></div> +<div class="paragraph"><p>We’ll make a number of commits here in order to demonstrate how to send a topic +with multiple patches up for review simultaneously.</p></div> +</div> +</div> +</div> +<div class="sect1"> +<h2 id="code-it-up">Code It Up!</h2> +<div class="sectionbody"> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">A reference implementation can be found at +<a href="https://github.com/nasamuffin/git/tree/psuh">https://github.com/nasamuffin/git/tree/psuh</a>.</td> +</tr></table> +</div> +<div class="sect2"> +<h3 id="add-new-command">Adding a New Command</h3> +<div class="paragraph"><p>Lots of the subcommands are written as builtins, which means they are +implemented in C and compiled into the main <code>git</code> executable. Implementing the +very simple <code>psuh</code> command as a built-in will demonstrate the structure of the +codebase, the internal API, and the process of working together as a contributor +with the reviewers and maintainer to integrate this change into the system.</p></div> +<div class="paragraph"><p>Built-in subcommands are typically implemented in a function named "cmd_" +followed by the name of the subcommand, in a source file named after the +subcommand and contained within <code>builtin/</code>. So it makes sense to implement your +command in <code>builtin/psuh.c</code>. Create that file, and within it, write the entry +point for your command in a function matching the style and signature:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>int cmd_psuh(int argc, const char **argv, const char *prefix)</code></pre> +</div></div> +<div class="paragraph"><p>We’ll also need to add the declaration of psuh; open up <code>builtin.h</code>, find the +declaration for <code>cmd_push</code>, and add a new line for <code>psuh</code> immediately before it, +in order to keep the declarations sorted:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>int cmd_psuh(int argc, const char **argv, const char *prefix);</code></pre> +</div></div> +<div class="paragraph"><p>Be sure to <code>#include "builtin.h"</code> in your <code>psuh.c</code>.</p></div> +<div class="paragraph"><p>Go ahead and add some throwaway printf to that function. This is a decent +starting point as we can now add build rules and register the command.</p></div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">Your throwaway text, as well as much of the text you will be adding over +the course of this tutorial, is user-facing. That means it needs to be +localizable. Take a look at <code>po/README</code> under "Marking strings for translation". +Throughout the tutorial, we will mark strings for translation as necessary; you +should also do so when writing your user-facing commands in the future.</td> +</tr></table> +</div> +<div class="listingblock"> +<div class="content"> +<pre><code>int cmd_psuh(int argc, const char **argv, const char *prefix) +{ + printf(_("Pony saying hello goes here.\n")); + return 0; +}</code></pre> +</div></div> +<div class="paragraph"><p>Let’s try to build it. Open <code>Makefile</code>, find where <code>builtin/push.o</code> is added +to <code>BUILTIN_OBJS</code>, and add <code>builtin/psuh.o</code> in the same way next to it in +alphabetical order. Once you’ve done so, move to the top-level directory and +build simply with <code>make</code>. Also add the <code>DEVELOPER=1</code> variable to turn on +some additional warnings:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ echo DEVELOPER=1 >config.mak +$ make</code></pre> +</div></div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">When you are developing the Git project, it’s preferred that you use the +<code>DEVELOPER</code> flag; if there’s some reason it doesn’t work for you, you can turn +it off, but it’s a good idea to mention the problem to the mailing list.</td> +</tr></table> +</div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">The Git build is parallelizable. <code>-j#</code> is not included above but you can +use it as you prefer, here and elsewhere.</td> +</tr></table> +</div> +<div class="paragraph"><p>Great, now your new command builds happily on its own. But nobody invokes it. +Let’s change that.</p></div> +<div class="paragraph"><p>The list of commands lives in <code>git.c</code>. We can register a new command by adding +a <code>cmd_struct</code> to the <code>commands[]</code> array. <code>struct cmd_struct</code> takes a string +with the command name, a function pointer to the command implementation, and a +setup option flag. For now, let’s keep mimicking <code>push</code>. Find the line where +<code>cmd_push</code> is registered, copy it, and modify it for <code>cmd_psuh</code>, placing the new +line in alphabetical order.</p></div> +<div class="paragraph"><p>The options are documented in <code>builtin.h</code> under "Adding a new built-in." Since +we hope to print some data about the user’s current workspace context later, +we need a Git directory, so choose <code>RUN_SETUP</code> as your only option.</p></div> +<div class="paragraph"><p>Go ahead and build again. You should see a clean build, so let’s kick the tires +and see if it works. There’s a binary you can use to test with in the +<code>bin-wrappers</code> directory.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ ./bin-wrappers/git psuh</code></pre> +</div></div> +<div class="paragraph"><p>Check it out! You’ve got a command! Nice work! Let’s commit this.</p></div> +<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 +untracked <code>builtin/psuh.c</code> and <code>git-psuh</code>. First, let’s take care of the binary, +which should be ignored. Open <code>.gitignore</code> in your editor, find <code>/git-push</code>, and +add an entry for your new command in alphabetical order:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>... +/git-prune-packed +/git-psuh +/git-pull +/git-push +/git-quiltimport +/git-range-diff +...</code></pre> +</div></div> +<div class="paragraph"><p>Checking <code>git status</code> again should show that <code>git-psuh</code> has been removed from +the untracked list and <code>.gitignore</code> has been added to the modified list. Now we +can stage and commit:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git add Makefile builtin.h builtin/psuh.c git.c .gitignore +$ git commit -s</code></pre> +</div></div> +<div class="paragraph"><p>You will be presented with your editor in order to write a commit message. Start +the commit with a 50-column or less subject line, including the name of the +component you’re working on, followed by a blank line (always required) and then +the body of your commit message, which should provide the bulk of the context. +Remember to be explicit and provide the "Why" of your change, especially if it +couldn’t easily be understood from your diff. When editing your commit message, +don’t remove the Signed-off-by line which was added by <code>-s</code> above.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>psuh: add a built-in by popular demand + +Internal metrics indicate this is a command many users expect to be +present. So here's an implementation to help drive customer +satisfaction and engagement: a pony which doubtfully greets the user, +or, a Pony Saying "Um, Hello" (PSUH). + +This commit message is intentionally formatted to 72 columns per line, +starts with a single line as "commit message subject" that is written as +if to command the codebase to do something (add this, teach a command +that). The body of the message is designed to add information about the +commit that is not readily deduced from reading the associated diff, +such as answering the question "why?". + +Signed-off-by: A U Thor <author@example.com></code></pre> +</div></div> +<div class="paragraph"><p>Go ahead and inspect your new commit with <code>git show</code>. "psuh:" indicates you +have modified mainly the <code>psuh</code> command. The subject line gives readers an idea +of what you’ve changed. The sign-off line (<code>-s</code>) indicates that you agree to +the Developer’s Certificate of Origin 1.1 (see the +<code>Documentation/SubmittingPatches</code> [[dco]] header).</p></div> +<div class="paragraph"><p>For the remainder of the tutorial, the subject line only will be listed for the +sake of brevity. However, fully-fleshed example commit messages are available +on the reference implementation linked at the top of this document.</p></div> +</div> +<div class="sect2"> +<h3 id="implementation">Implementation</h3> +<div class="paragraph"><p>It’s probably useful to do at least something besides printing out a string. +Let’s start by having a look at everything we get.</p></div> +<div class="paragraph"><p>Modify your <code>cmd_psuh</code> implementation to dump the args you’re passed, keeping +existing <code>printf()</code> calls in place:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code> int i; + + ... + + printf(Q_("Your args (there is %d):\n", + "Your args (there are %d):\n", + argc), + argc); + for (i = 0; i < argc; i++) + printf("%d: %s\n", i, argv[i]); + + printf(_("Your current working directory:\n<top-level>%s%s\n"), + prefix ? "/" : "", prefix ? prefix : "");</code></pre> +</div></div> +<div class="paragraph"><p>Build and try it. As you may expect, there’s pretty much just whatever we give +on the command line, including the name of our command. (If <code>prefix</code> is empty +for you, try <code>cd Documentation/ && ../bin-wrappers/git psuh</code>). That’s not so +helpful. So what other context can we get?</p></div> +<div class="paragraph"><p>Add a line to <code>#include "config.h"</code>. Then, add the following bits to the +function body:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code> const char *cfg_name; + +... + + git_config(git_default_config, NULL); + if (git_config_get_string_const("user.name", &cfg_name) > 0) + printf(_("No name is found in config\n")); + else + printf(_("Your name: %s\n"), cfg_name);</code></pre> +</div></div> +<div class="paragraph"><p><code>git_config()</code> will grab the configuration from config files known to Git and +apply standard precedence rules. <code>git_config_get_string_const()</code> will look up +a specific key ("user.name") and give you the value. There are a number of +single-key lookup functions like this one; you can see them all (and more info +about how to use <code>git_config()</code>) in <code>Documentation/technical/api-config.txt</code>.</p></div> +<div class="paragraph"><p>You should see that the name printed matches the one you see when you run:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git config --get user.name</code></pre> +</div></div> +<div class="paragraph"><p>Great! Now we know how to check for values in the Git config. Let’s commit this +too, so we don’t lose our progress.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git add builtin/psuh.c +$ git commit -sm "psuh: show parameters & config opts"</code></pre> +</div></div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">Again, the above is for sake of brevity in this tutorial. In a real change +you should not use <code>-m</code> but instead use the editor to write a meaningful +message.</td> +</tr></table> +</div> +<div class="paragraph"><p>Still, it’d be nice to know what the user’s working context is like. Let’s see +if we can print the name of the user’s current branch. We can mimic the +<code>git status</code> implementation; the printer is located in <code>wt-status.c</code> and we can +see that the branch is held in a <code>struct wt_status</code>.</p></div> +<div class="paragraph"><p><code>wt_status_print()</code> gets invoked by <code>cmd_status()</code> in <code>builtin/commit.c</code>. +Looking at that implementation we see the status config being populated like so:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>status_init_config(&s, git_status_config);</code></pre> +</div></div> +<div class="paragraph"><p>But as we drill down, we can find that <code>status_init_config()</code> wraps a call +to <code>git_config()</code>. Let’s modify the code we wrote in the previous commit.</p></div> +<div class="paragraph"><p>Be sure to include the header to allow you to use <code>struct wt_status</code>:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>#include "wt-status.h"</code></pre> +</div></div> +<div class="paragraph"><p>Then modify your <code>cmd_psuh</code> implementation to declare your <code>struct wt_status</code>, +prepare it, and print its contents:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code> struct wt_status status; + +... + + wt_status_prepare(the_repository, &status); + git_config(git_default_config, &status); + +... + + printf(_("Your current branch: %s\n"), status.branch);</code></pre> +</div></div> +<div class="paragraph"><p>Run it again. Check it out - here’s the (verbose) name of your current branch!</p></div> +<div class="paragraph"><p>Let’s commit this as well.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git add builtin/psuh.c +$ git commit -sm "psuh: print the current branch"</code></pre> +</div></div> +<div class="paragraph"><p>Now let’s see if we can get some info about a specific commit.</p></div> +<div class="paragraph"><p>Luckily, there are some helpers for us here. <code>commit.h</code> has a function called +<code>lookup_commit_reference_by_name</code> to which we can simply provide a hardcoded +string; <code>pretty.h</code> has an extremely handy <code>pp_commit_easy()</code> call which doesn’t +require a full format object to be passed.</p></div> +<div class="paragraph"><p>Add the following includes:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>#include "commit.h" +#include "pretty.h"</code></pre> +</div></div> +<div class="paragraph"><p>Then, add the following lines within your implementation of <code>cmd_psuh()</code> near +the declarations and the logic, respectively.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code> struct commit *c = NULL; + struct strbuf commitline = STRBUF_INIT; + +... + + c = lookup_commit_reference_by_name("origin/master"); + + if (c != NULL) { + pp_commit_easy(CMIT_FMT_ONELINE, c, &commitline); + printf(_("Current commit: %s\n"), commitline.buf); + }</code></pre> +</div></div> +<div class="paragraph"><p>The <code>struct strbuf</code> provides some safety belts to your basic <code>char*</code>, one of +which is a length member to prevent buffer overruns. It needs to be initialized +nicely with <code>STRBUF_INIT</code>. Keep it in mind when you need to pass around <code>char*</code>.</p></div> +<div class="paragraph"><p><code>lookup_commit_reference_by_name</code> resolves the name you pass it, so you can play +with the value there and see what kind of things you can come up with.</p></div> +<div class="paragraph"><p><code>pp_commit_easy</code> is a convenience wrapper in <code>pretty.h</code> that takes a single +format enum shorthand, rather than an entire format struct. It then +pretty-prints the commit according to that shorthand. These are similar to the +formats available with <code>--pretty=FOO</code> in many Git commands.</p></div> +<div class="paragraph"><p>Build it and run, and if you’re using the same name in the example, you should +see the subject line of the most recent commit in <code>origin/master</code> that you know +about. Neat! Let’s commit that as well.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git add builtin/psuh.c +$ git commit -sm "psuh: display the top of origin/master"</code></pre> +</div></div> +</div> +<div class="sect2"> +<h3 id="add-documentation">Adding Documentation</h3> +<div class="paragraph"><p>Awesome! You’ve got a fantastic new command that you’re ready to share with the +community. But hang on just a minute - this isn’t very user-friendly. Run the +following:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ ./bin-wrappers/git help psuh</code></pre> +</div></div> +<div class="paragraph"><p>Your new command is undocumented! Let’s fix that.</p></div> +<div class="paragraph"><p>Take a look at <code>Documentation/git-*.txt</code>. These are the manpages for the +subcommands that Git knows about. You can open these up and take a look to get +acquainted with the format, but then go ahead and make a new file +<code>Documentation/git-psuh.txt</code>. Like with most of the documentation in the Git +project, help pages are written with AsciiDoc (see CodingGuidelines, "Writing +Documentation" section). Use the following template to fill out your own +manpage:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>git-psuh(1) +=========== + +NAME +---- +git-psuh - Delight users' typo with a shy horse + + +SYNOPSIS +-------- +[verse] +'git-psuh' + +DESCRIPTION +----------- +... + +OPTIONS[[OPTIONS]] +------------------ +... + +OUTPUT +------ +... + +GIT +--- +Part of the linkgit:git[1] suite</code></pre> +</div></div> +<div class="paragraph"><p>The most important pieces of this to note are the file header, underlined by =, +the NAME section, and the SYNOPSIS, which would normally contain the grammar if +your command took arguments. Try to use well-established manpage headers so your +documentation is consistent with other Git and UNIX manpages; this makes life +easier for your user, who can skip to the section they know contains the +information they need.</p></div> +<div class="paragraph"><p>Now that you’ve written your manpage, you’ll need to build it explicitly. We +convert your AsciiDoc to troff which is man-readable like so:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ make all doc +$ man Documentation/git-psuh.1</code></pre> +</div></div> +<div class="paragraph"><p>or</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ make -C Documentation/ git-psuh.1 +$ man Documentation/git-psuh.1</code></pre> +</div></div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">You may need to install the package <code>asciidoc</code> to get this to work.</td> +</tr></table> +</div> +<div class="paragraph"><p>While this isn’t as satisfying as running through <code>git help</code>, you can at least +check that your help page looks right.</p></div> +<div class="paragraph"><p>You can also check that the documentation coverage is good (that is, the project +sees that your command has been implemented as well as documented) by running +<code>make check-docs</code> from the top-level.</p></div> +<div class="paragraph"><p>Go ahead and commit your new documentation change.</p></div> +</div> +<div class="sect2"> +<h3 id="add-usage">Adding Usage Text</h3> +<div class="paragraph"><p>Try and run <code>./bin-wrappers/git psuh -h</code>. Your command should crash at the end. +That’s because <code>-h</code> is a special case which your command should handle by +printing usage.</p></div> +<div class="paragraph"><p>Take a look at <code>Documentation/technical/api-parse-options.txt</code>. This is a handy +tool for pulling out options you need to be able to handle, and it takes a +usage string.</p></div> +<div class="paragraph"><p>In order to use it, we’ll need to prepare a NULL-terminated usage string and a +<code>builtin_psuh_options</code> array. Add a line to <code>#include "parse-options.h"</code>.</p></div> +<div class="paragraph"><p>At global scope, add your usage:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>static const char * const psuh_usage[] = { + N_("git psuh"), + NULL, +};</code></pre> +</div></div> +<div class="paragraph"><p>Then, within your <code>cmd_psuh()</code> implementation, we can declare and populate our +<code>option</code> struct. Ours is pretty boring but you can add more to it if you want to +explore <code>parse_options()</code> in more detail:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code> struct option options[] = { + OPT_END() + };</code></pre> +</div></div> +<div class="paragraph"><p>Finally, before you print your args and prefix, add the call to +<code>parse-options()</code>:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code> argc = parse_options(argc, argv, prefix, options, psuh_usage, 0);</code></pre> +</div></div> +<div class="paragraph"><p>This call will modify your <code>argv</code> parameter. It will strip the options you +specified in <code>options</code> from <code>argv</code> and the locations pointed to from <code>options</code> +entries will be updated. Be sure to replace your <code>argc</code> with the result from +<code>parse_options()</code>, or you will be confused if you try to parse <code>argv</code> later.</p></div> +<div class="paragraph"><p>It’s worth noting the special argument <code>--</code>. As you may be aware, many Unix +commands use <code>--</code> to indicate "end of named parameters" - all parameters after +the <code>--</code> are interpreted merely as positional arguments. (This can be handy if +you want to pass as a parameter something which would usually be interpreted as +a flag.) <code>parse_options()</code> will terminate parsing when it reaches <code>--</code> and give +you the rest of the options afterwards, untouched.</p></div> +<div class="paragraph"><p>Build again. Now, when you run with <code>-h</code>, you should see your usage printed and +your command terminated before anything else interesting happens. Great!</p></div> +<div class="paragraph"><p>Go ahead and commit this one, too.</p></div> +</div> +</div> +</div> +<div class="sect1"> +<h2 id="testing">Testing</h2> +<div class="sectionbody"> +<div class="paragraph"><p>It’s important to test your code - even for a little toy command like this one. +Moreover, your patch won’t be accepted into the Git tree without tests. Your +tests should:</p></div> +<div class="ulist"><ul> +<li> +<p> +Illustrate the current behavior of the feature +</p> +</li> +<li> +<p> +Prove the current behavior matches the expected behavior +</p> +</li> +<li> +<p> +Ensure the externally-visible behavior isn’t broken in later changes +</p> +</li> +</ul></div> +<div class="paragraph"><p>So let’s write some tests.</p></div> +<div class="paragraph"><p>Related reading: <code>t/README</code></p></div> +<div class="sect2"> +<h3 id="overview-test-structure">Overview of Testing Structure</h3> +<div class="paragraph"><p>The tests in Git live in <code>t/</code> and are named with a 4-digit decimal number using +the schema shown in the Naming Tests section of <code>t/README</code>.</p></div> +</div> +<div class="sect2"> +<h3 id="write-new-test">Writing Your Test</h3> +<div class="paragraph"><p>Since this a toy command, let’s go ahead and name the test with t9999. However, +as many of the family/subcmd combinations are full, best practice seems to be +to find a command close enough to the one you’ve added and share its naming +space.</p></div> +<div class="paragraph"><p>Create a new file <code>t/t9999-psuh-tutorial.sh</code>. Begin with the header as so (see +"Writing Tests" and "Source <em>test-lib.sh</em>" in <code>t/README</code>):</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>#!/bin/sh + +test_description='git-psuh test + +This test runs git-psuh and makes sure it does not crash.' + +. ./test-lib.sh</code></pre> +</div></div> +<div class="paragraph"><p>Tests are framed inside of a <code>test_expect_success</code> in order to output TAP +formatted results. Let’s make sure that <code>git psuh</code> doesn’t exit poorly and does +mention the right animal somewhere:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>test_expect_success 'runs correctly with no args and good output' ' + git psuh >actual && + test_i18ngrep Pony actual +'</code></pre> +</div></div> +<div class="paragraph"><p>Indicate that you’ve run everything you wanted by adding the following at the +bottom of your script:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>test_done</code></pre> +</div></div> +<div class="paragraph"><p>Make sure you mark your test script executable:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ chmod +x t/t9999-psuh-tutorial.sh</code></pre> +</div></div> +<div class="paragraph"><p>You can get an idea of whether you created your new test script successfully +by running <code>make -C t test-lint</code>, which will check for things like test number +uniqueness, executable bit, and so on.</p></div> +</div> +<div class="sect2"> +<h3 id="local-test">Running Locally</h3> +<div class="paragraph"><p>Let’s try and run locally:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ make +$ cd t/ && prove t9999-psuh-tutorial.sh</code></pre> +</div></div> +<div class="paragraph"><p>You can run the full test suite and ensure <code>git-psuh</code> didn’t break anything:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ cd t/ +$ prove -j$(nproc) --shuffle t[0-9]*.sh</code></pre> +</div></div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">You can also do this with <code>make test</code> or use any testing harness which can +speak TAP. <code>prove</code> can run concurrently. <code>shuffle</code> randomizes the order the +tests are run in, which makes them resilient against unwanted inter-test +dependencies. <code>prove</code> also makes the output nicer.</td> +</tr></table> +</div> +<div class="paragraph"><p>Go ahead and commit this change, as well.</p></div> +</div> +</div> +</div> +<div class="sect1"> +<h2 id="ready-to-share">Getting Ready to Share</h2> +<div class="sectionbody"> +<div class="paragraph"><p>You may have noticed already that the Git project performs its code reviews via +emailed patches, which are then applied by the maintainer when they are ready +and approved by the community. The Git project does not accept patches from +pull requests, and the patches emailed for review need to be formatted a +specific way. At this point the tutorial diverges, in order to demonstrate two +different methods of formatting your patchset and getting it reviewed.</p></div> +<div class="paragraph"><p>The first method to be covered is GitGitGadget, which is useful for those +already familiar with GitHub’s common pull request workflow. This method +requires a GitHub account.</p></div> +<div class="paragraph"><p>The second method to be covered is <code>git send-email</code>, which can give slightly +more fine-grained control over the emails to be sent. This method requires some +setup which can change depending on your system and will not be covered in this +tutorial.</p></div> +<div class="paragraph"><p>Regardless of which method you choose, your engagement with reviewers will be +the same; the review process will be covered after the sections on GitGitGadget +and <code>git send-email</code>.</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="howto-ggg">Sending Patches via GitGitGadget</h2> +<div class="sectionbody"> +<div class="paragraph"><p>One option for sending patches is to follow a typical pull request workflow and +send your patches out via GitGitGadget. GitGitGadget is a tool created by +Johannes Schindelin to make life as a Git contributor easier for those used to +the GitHub PR workflow. It allows contributors to open pull requests against its +mirror of the Git project, and does some magic to turn the PR into a set of +emails and send them out for you. It also runs the Git continuous integration +suite for you. It’s documented at <a href="http://gitgitgadget.github.io">http://gitgitgadget.github.io</a>.</p></div> +<div class="sect2"> +<h3 id="create-fork">Forking <code>git/git</code> on GitHub</h3> +<div class="paragraph"><p>Before you can send your patch off to be reviewed using GitGitGadget, you will +need to fork the Git project and upload your changes. First thing - make sure +you have a GitHub account.</p></div> +<div class="paragraph"><p>Head to the <a href="https://github.com/git/git">GitHub mirror</a> and look for the Fork +button. Place your fork wherever you deem appropriate and create it.</p></div> +</div> +<div class="sect2"> +<h3 id="upload-to-fork">Uploading to Your Own Fork</h3> +<div class="paragraph"><p>To upload your branch to your own fork, you’ll need to add the new fork as a +remote. You can use <code>git remote -v</code> to show the remotes you have added already. +From your new fork’s page on GitHub, you can press "Clone or download" to get +the URL; then you need to run the following to add, replacing your own URL and +remote name for the examples provided:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git remote add remotename git@github.com:remotename/git.git</code></pre> +</div></div> +<div class="paragraph"><p>or to use the HTTPS URL:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git remote add remotename https://github.com/remotename/git/.git</code></pre> +</div></div> +<div class="paragraph"><p>Run <code>git remote -v</code> again and you should see the new remote showing up. +<code>git fetch remotename</code> (with the real name of your remote replaced) in order to +get ready to push.</p></div> +<div class="paragraph"><p>Next, double-check that you’ve been doing all your development in a new branch +by running <code>git branch</code>. If you didn’t, now is a good time to move your new +commits to their own branch.</p></div> +<div class="paragraph"><p>As mentioned briefly at the beginning of this document, we are basing our work +on <code>master</code>, so go ahead and update as shown below, or using your preferred +workflow.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git checkout master +$ git pull -r +$ git rebase master psuh</code></pre> +</div></div> +<div class="paragraph"><p>Finally, you’re ready to push your new topic branch! (Due to our branch and +command name choices, be careful when you type the command below.)</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git push remotename psuh</code></pre> +</div></div> +<div class="paragraph"><p>Now you should be able to go and check out your newly created branch on GitHub.</p></div> +</div> +<div class="sect2"> +<h3 id="send-pr-ggg">Sending a PR to GitGitGadget</h3> +<div class="paragraph"><p>In order to have your code tested and formatted for review, you need to start by +opening a Pull Request against <code>gitgitgadget/git</code>. Head to +<a href="https://github.com/gitgitgadget/git">https://github.com/gitgitgadget/git</a> and open a PR either with the "New pull +request" button or the convenient "Compare & pull request" button that may +appear with the name of your newly pushed branch.</p></div> +<div class="paragraph"><p>Review the PR’s title and description, as it’s used by GitGitGadget as the cover +letter for your change. When you’re happy, submit your pull request.</p></div> +</div> +<div class="sect2"> +<h3 id="run-ci-ggg">Running CI and Getting Ready to Send</h3> +<div class="paragraph"><p>If it’s your first time using GitGitGadget (which is likely, as you’re using +this tutorial) then someone will need to give you permission to use the tool. +As mentioned in the GitGitGadget documentation, you just need someone who +already uses it to comment on your PR with <code>/allow <username></code>. GitGitGadget +will automatically run your PRs through the CI even without the permission given +but you will not be able to <code>/submit</code> your changes until someone allows you to +use the tool.</p></div> +<div class="paragraph"><p>If the CI fails, you can update your changes with <code>git rebase -i</code> and push your +branch again:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git push -f remotename psuh</code></pre> +</div></div> +<div class="paragraph"><p>In fact, you should continue to make changes this way up until the point when +your patch is accepted into <code>next</code>.</p></div> +</div> +<div class="sect2"> +<h3 id="send-mail-ggg">Sending Your Patches</h3> +<div class="paragraph"><p>Now that your CI is passing and someone has granted you permission to use +GitGitGadget with the <code>/allow</code> command, sending out for review is as simple as +commenting on your PR with <code>/submit</code>.</p></div> +</div> +<div class="sect2"> +<h3 id="responding-ggg">Updating With Comments</h3> +<div class="paragraph"><p>Skip ahead to <a href="#reviewing">Responding to Reviews</a> for information on how to +reply to review comments you will receive on the mailing list.</p></div> +<div class="paragraph"><p>Once you have your branch again in the shape you want following all review +comments, you can submit again:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git push -f remotename psuh</code></pre> +</div></div> +<div class="paragraph"><p>Next, go look at your pull request against GitGitGadget; you should see the CI +has been kicked off again. Now while the CI is running is a good time for you +to modify your description at the top of the pull request thread; it will be +used again as the cover letter. You should use this space to describe what +has changed since your previous version, so that your reviewers have some idea +of what they’re looking at. When the CI is done running, you can comment once +more with <code>/submit</code> - GitGitGadget will automatically add a v2 mark to your +changes.</p></div> +</div> +</div> +</div> +<div class="sect1"> +<h2 id="howto-git-send-email">Sending Patches with <code>git send-email</code></h2> +<div class="sectionbody"> +<div class="paragraph"><p>If you don’t want to use GitGitGadget, you can also use Git itself to mail your +patches. Some benefits of using Git this way include finer grained control of +subject line (for example, being able to use the tag [RFC PATCH] in the subject) +and being able to send a “dry run” mail to yourself to ensure it all looks +good before going out to the list.</p></div> +<div class="sect2"> +<h3 id="setup-git-send-email">Prerequisite: Setting Up <code>git send-email</code></h3> +<div class="paragraph"><p>Configuration for <code>send-email</code> can vary based on your operating system and email +provider, and so will not be covered in this tutorial, beyond stating that in +many distributions of Linux, <code>git-send-email</code> is not packaged alongside the +typical <code>git</code> install. You may need to install this additional package; there +are a number of resources online to help you do so. You will also need to +determine the right way to configure it to use your SMTP server; again, as this +configuration can change significantly based on your system and email setup, it +is out of scope for the context of this tutorial.</p></div> +</div> +<div class="sect2"> +<h3 id="format-patch">Preparing Initial Patchset</h3> +<div class="paragraph"><p>Sending emails with Git is a two-part process; before you can prepare the emails +themselves, you’ll need to prepare the patches. Luckily, this is pretty simple:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git format-patch --cover-letter -o psuh/ master..psuh</code></pre> +</div></div> +<div class="paragraph"><p>The <code>--cover-letter</code> parameter tells <code>format-patch</code> to create a cover letter +template for you. You will need to fill in the template before you’re ready +to send - but for now, the template will be next to your other patches.</p></div> +<div class="paragraph"><p>The <code>-o psuh/</code> parameter tells <code>format-patch</code> to place the patch files into a +directory. This is useful because <code>git send-email</code> can take a directory and +send out all the patches from there.</p></div> +<div class="paragraph"><p><code>master..psuh</code> tells <code>format-patch</code> to generate patches for the difference +between <code>master</code> and <code>psuh</code>. It will make one patch file per commit. After you +run, you can go have a look at each of the patches with your favorite text +editor and make sure everything looks alright; however, it’s not recommended to +make code fixups via the patch file. It’s a better idea to make the change the +normal way using <code>git rebase -i</code> or by adding a new commit than by modifying a +patch.</p></div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">Optionally, you can also use the <code>--rfc</code> flag to prefix your patch subject +with “[RFC PATCH]” instead of “[PATCH]”. RFC stands for “request for +comments” and indicates that while your code isn’t quite ready for submission, +you’d like to begin the code review process. This can also be used when your +patch is a proposal, but you aren’t sure whether the community wants to solve +the problem with that approach or not - to conduct a sort of design review. You +may also see on the list patches marked “WIP” - this means they are incomplete +but want reviewers to look at what they have so far. You can add this flag with +<code>--subject-prefix=WIP</code>.</td> +</tr></table> +</div> +<div class="paragraph"><p>Check and make sure that your patches and cover letter template exist in the +directory you specified - you’re nearly ready to send out your review!</p></div> +</div> +<div class="sect2"> +<h3 id="cover-letter">Preparing Email</h3> +<div class="paragraph"><p>In addition to an email per patch, the Git community also expects your patches +to come with a cover letter, typically with a subject line [PATCH 0/x] (where +x is the number of patches you’re sending). Since you invoked <code>format-patch</code> +with <code>--cover-letter</code>, you’ve already got a template ready. Open it up in your +favorite editor.</p></div> +<div class="paragraph"><p>You should see a number of headers present already. Check that your <code>From:</code> +header is correct. Then modify your <code>Subject:</code> to something which succinctly +covers the purpose of your entire topic branch, for example:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>Subject: [PATCH 0/7] adding the 'psuh' command</code></pre> +</div></div> +<div class="paragraph"><p>Make sure you retain the “[PATCH 0/X]” part; that’s what indicates to the Git +community that this email is the beginning of a review, and many reviewers +filter their email for this type of flag.</p></div> +<div class="paragraph"><p>You’ll need to add some extra parameters when you invoke <code>git send-email</code> to add +the cover letter.</p></div> +<div class="paragraph"><p>Next you’ll have to fill out the body of your cover letter. This is an important +component of change submission as it explains to the community from a high level +what you’re trying to do, and why, in a way that’s more apparent than just +looking at your diff. Be sure to explain anything your diff doesn’t make clear +on its own.</p></div> +<div class="paragraph"><p>Here’s an example body for <code>psuh</code>:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>Our internal metrics indicate widespread interest in the command +git-psuh - that is, many users are trying to use it, but finding it is +unavailable, using some unknown workaround instead. + +The following handful of patches add the psuh command and implement some +handy features on top of it. + +This patchset is part of the MyFirstContribution tutorial and should not +be merged.</code></pre> +</div></div> +<div class="paragraph"><p>The template created by <code>git format-patch --cover-letter</code> includes a diffstat. +This gives reviewers a summary of what they’re in for when reviewing your topic. +The one generated for <code>psuh</code> from the sample implementation looks like this:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code> Documentation/git-psuh.txt | 40 +++++++++++++++++++++ + Makefile | 1 + + builtin.h | 1 + + builtin/psuh.c | 73 ++++++++++++++++++++++++++++++++++++++ + git.c | 1 + + t/t9999-psuh-tutorial.sh | 12 +++++++ + 6 files changed, 128 insertions(+) + create mode 100644 Documentation/git-psuh.txt + create mode 100644 builtin/psuh.c + create mode 100755 t/t9999-psuh-tutorial.sh</code></pre> +</div></div> +<div class="paragraph"><p>Finally, the letter will include the version of Git used to generate the +patches. You can leave that string alone.</p></div> +</div> +<div class="sect2"> +<h3 id="sending-git-send-email">Sending Email</h3> +<div class="paragraph"><p>At this point you should have a directory <code>psuh/</code> which is filled with your +patches and a cover letter. Time to mail it out! You can send it like this:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git send-email --to=target@example.com psuh/*.patch</code></pre> +</div></div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<td class="content">Check <code>git help send-email</code> for some other options which you may find +valuable, such as changing the Reply-to address or adding more CC and BCC lines.</td> +</tr></table> +</div> +<div class="admonitionblock"> +<table><tr> +<td class="icon"> +<div class="title">Note</div> +</td> +<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 +please don’t send your patchset from the tutorial to the real mailing list! For +now, you can send it to yourself, to make sure you understand how it will look.</td> +</tr></table> +</div> +<div class="paragraph"><p>After you run the command above, you will be presented with an interactive +prompt for each patch that’s about to go out. This gives you one last chance to +edit or quit sending something (but again, don’t edit code this way). Once you +press <code>y</code> or <code>a</code> at these prompts your emails will be sent! Congratulations!</p></div> +<div class="paragraph"><p>Awesome, now the community will drop everything and review your changes. (Just +kidding - be patient!)</p></div> +</div> +<div class="sect2"> +<h3 id="v2-git-send-email">Sending v2</h3> +<div class="paragraph"><p>Skip ahead to <a href="#reviewing">Responding to Reviews</a> for information on how to +handle comments from reviewers. Continue this section when your topic branch is +shaped the way you want it to look for your patchset v2.</p></div> +<div class="paragraph"><p>When you’re ready with the next iteration of your patch, the process is fairly +similar.</p></div> +<div class="paragraph"><p>First, generate your v2 patches again:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git format-patch -v2 --cover-letter -o psuh/ master..psuh</code></pre> +</div></div> +<div class="paragraph"><p>This will add your v2 patches, all named like <code>v2-000n-my-commit-subject.patch</code>, +to the <code>psuh/</code> directory. You may notice that they are sitting alongside the v1 +patches; that’s fine, but be careful when you are ready to send them.</p></div> +<div class="paragraph"><p>Edit your cover letter again. Now is a good time to mention what’s different +between your last version and now, if it’s something significant. You do not +need the exact same body in your second cover letter; focus on explaining to +reviewers the changes you’ve made that may not be as visible.</p></div> +<div class="paragraph"><p>You will also need to go and find the Message-Id of your previous cover letter. +You can either note it when you send the first series, from the output of <code>git +send-email</code>, or you can look it up on the +<a href="https://public-inbox.org/git">mailing list</a>. Find your cover letter in the +archives, click on it, then click "permalink" or "raw" to reveal the Message-Id +header. It should match:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>Message-Id: <foo.12345.author@example.com></code></pre> +</div></div> +<div class="paragraph"><p>Your Message-Id is <code><foo.12345.author@example.com></code>. This example will be used +below as well; make sure to replace it with the correct Message-Id for your +<strong>previous cover letter</strong> - that is, if you’re sending v2, use the Message-Id +from v1; if you’re sending v3, use the Message-Id from v2.</p></div> +<div class="paragraph"><p>While you’re looking at the email, you should also note who is CC’d, as it’s +common practice in the mailing list to keep all CCs on a thread. You can add +these CC lines directly to your cover letter with a line like so in the header +(before the Subject line):</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>CC: author@example.com, Othe R <other@example.com></code></pre> +</div></div> +<div class="paragraph"><p>Now send the emails again, paying close attention to which messages you pass in +to the command:</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git send-email --to=target@example.com + --in-reply-to="<foo.12345.author@example.com>" + psuh/v2*</code></pre> +</div></div> +</div> +<div class="sect2"> +<h3 id="single-patch">Bonus Chapter: One-Patch Changes</h3> +<div class="paragraph"><p>In some cases, your very small change may consist of only one patch. When that +happens, you only need to send one email. Your commit message should already be +meaningful and explain at a high level the purpose (what is happening and why) +of your patch, but if you need to supply even more context, you can do so below +the <code>---</code> in your patch. Take the example below, which was generated with <code>git +format-patch</code> on a single commit, and then edited to add the content between +the <code>---</code> and the diffstat.</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>From 1345bbb3f7ac74abde040c12e737204689a72723 Mon Sep 17 00:00:00 2001 +From: A U Thor <author@example.com> +Date: Thu, 18 Apr 2019 15:11:02 -0700 +Subject: [PATCH] README: change the grammar + +I think it looks better this way. This part of the commit message will +end up in the commit-log. + +Signed-off-by: A U Thor <author@example.com> +--- +Let's have a wild discussion about grammar on the mailing list. This +part of my email will never end up in the commit log. Here is where I +can add additional context to the mailing list about my intent, outside +of the context of the commit log. This section was added after `git +format-patch` was run, by editing the patch file in a text editor. + + README.md | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/README.md b/README.md +index 88f126184c..38da593a60 100644 +--- a/README.md ++++ b/README.md +@@ -3,7 +3,7 @@ + Git - fast, scalable, distributed revision control system + ========================================================= + +-Git is a fast, scalable, distributed revision control system with an ++Git is a fast, scalable, and distributed revision control system with an + unusually rich command set that provides both high-level operations + and full access to internals. + +-- +2.21.0.392.gf8f6787159e-goog</code></pre> +</div></div> +</div> +</div> +</div> +<div class="sect1"> +<h2 id="now-what">My Patch Got Emailed - Now What?</h2> +<div class="sectionbody"> +<div class="sect2"> +<h3 id="reviewing">Responding to Reviews</h3> +<div class="paragraph"><p>After a few days, you will hopefully receive a reply to your patchset with some +comments. Woohoo! Now you can get back to work.</p></div> +<div class="paragraph"><p>It’s good manners to reply to each comment, notifying the reviewer that you have +made the change requested, feel the original is better, or that the comment +inspired you to do something a new way which is superior to both the original +and the suggested change. This way reviewers don’t need to inspect your v2 to +figure out whether you implemented their comment or not.</p></div> +<div class="paragraph"><p>If you are going to push back on a comment, be polite and explain why you feel +your original is better; be prepared that the reviewer may still disagree with +you, and the rest of the community may weigh in on one side or the other. As +with all code reviews, it’s important to keep an open mind to doing something a +different way than you originally planned; other reviewers have a different +perspective on the project than you do, and may be thinking of a valid side +effect which had not occurred to you. It is always okay to ask for clarification +if you aren’t sure why a change was suggested, or what the reviewer is asking +you to do.</p></div> +<div class="paragraph"><p>Make sure your email client has a plaintext email mode and it is turned on; the +Git list rejects HTML email. Please also follow the mailing list etiquette +outlined in the +<a href="https://kernel.googlesource.com/pub/scm/git/git/+/todo/MaintNotes">Maintainer’s +Note</a>, which are similar to etiquette rules in most open source communities +surrounding bottom-posting and inline replies.</p></div> +<div class="paragraph"><p>When you’re making changes to your code, it is cleanest - that is, the resulting +commits are easiest to look at - if you use <code>git rebase -i</code> (interactive +rebase). Take a look at this +<a href="https://www.oreilly.com/library/view/git-pocket-guide/9781449327507/ch10.html">overview</a> +from O’Reilly. The general idea is to modify each commit which requires changes; +this way, instead of having a patch A with a mistake, a patch B which was fine +and required no upstream reviews in v1, and a patch C which fixes patch A for +v2, you can just ship a v2 with a correct patch A and correct patch B. This is +changing history, but since it’s local history which you haven’t shared with +anyone, that is okay for now! (Later, it may not make sense to do this; take a +look at the section below this one for some context.)</p></div> +</div> +<div class="sect2"> +<h3 id="after-approval">After Review Approval</h3> +<div class="paragraph"><p>The Git project has four integration branches: <code>pu</code>, <code>next</code>, <code>master</code>, and +<code>maint</code>. Your change will be placed into <code>pu</code> fairly early on by the maintainer +while it is still in the review process; from there, when it is ready for wider +testing, it will be merged into <code>next</code>. Plenty of early testers use <code>next</code> and +may report issues. Eventually, changes in <code>next</code> will make it to <code>master</code>, +which is typically considered stable. Finally, when a new release is cut, +<code>maint</code> is used to base bugfixes onto. As mentioned at the beginning of this +document, you can read <code>Documents/SubmittingPatches</code> for some more info about +the use of the various integration branches.</p></div> +<div class="paragraph"><p>Back to now: your code has been lauded by the upstream reviewers. It is perfect. +It is ready to be accepted. You don’t need to do anything else; the maintainer +will merge your topic branch to <code>next</code> and life is good.</p></div> +<div class="paragraph"><p>However, if you discover it isn’t so perfect after this point, you may need to +take some special steps depending on where you are in the process.</p></div> +<div class="paragraph"><p>If the maintainer has announced in the "What’s cooking in git.git" email that +your topic is marked for <code>next</code> - that is, that they plan to merge it to <code>next</code> +but have not yet done so - you should send an email asking the maintainer to +wait a little longer: "I’ve sent v4 of my series and you marked it for <code>next</code>, +but I need to change this and that - please wait for v5 before you merge it."</p></div> +<div class="paragraph"><p>If the topic has already been merged to <code>next</code>, rather than modifying your +patches with <code>git rebase -i</code>, you should make further changes incrementally - +that is, with another commit, based on top of the maintainer’s topic branch as +detailed in <a href="https://github.com/gitster/git">https://github.com/gitster/git</a>. Your work is still in the same topic +but is now incremental, rather than a wholesale rewrite of the topic branch.</p></div> +<div class="paragraph"><p>The topic branches in the maintainer’s GitHub are mirrored in GitGitGadget, so +if you’re sending your reviews out that way, you should be sure to open your PR +against the appropriate GitGitGadget/Git branch.</p></div> +<div class="paragraph"><p>If you’re using <code>git send-email</code>, you can use it the same way as before, but you +should generate your diffs from <code><topic>..<mybranch></code> and base your work on +<code><topic></code> instead of <code>master</code>.</p></div> +</div> +</div> +</div> +</div> +<div id="footnotes"><hr /></div> +<div id="footer"> +<div id="footer-text"> +Last updated + 2019-06-17 20:21:34 PDT +</div> +</div> +</body> +</html> 