We are currently indexing your data, so search results may be incomplete until we finish.
|
|
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>HgInit: Ground Up Mercurial</title>
<script src="c/jquery-1.4.1.js"></script>
<script src="c/basic.js"></script>
<link href="c/styles.css" rel="stylesheet" type="text/css" />
<script type="text/javascript">
var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");
document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));
</script>
<script type="text/javascript">
try {
var pageTracker = _gat._getTracker("UA-225715-20");
pageTracker._setDomainName("none");
pageTracker._setAllowLinker(true);
pageTracker._trackPageview();
} catch(err) {}</script>
<!-- Google Website Optimizer Control Script -->
<script>
function utmx_section(){}function utmx(){}
(function(){var k='2687020024',d=document,l=d.location,c=d.cookie;function f(n){
if(c){var i=c.indexOf(n+'=');if(i>-1){var j=c.indexOf(';',i);return c.substring(i+n.
length+1,j<0?c.length:j)}}}var x=f('__utmx'),xx=f('__utmxx'),h=l.hash;
d.write('<sc'+'ript src="'+
'http'+(l.protocol=='https:'?'s://ssl':'://www')+'.google-analytics.com'
+'/siteopt.js?v=1&utmxkey='+k+'&utmx='+(x?x:'')+'&utmxx='+(xx?xx:'')+'&utmxtime='
+new Date().valueOf()+(h?'&utmxhash='+escape(h.substr(1)):'')+
'" type="text/javascript" charset="utf-8"></sc'+'ript>')})();
</script><script>utmx("url",'A/B');</script>
<!-- End of Google Website Optimizer Control Script -->
</head>
<body>
<div id="kilnFlyOut">
<div class="flyouttext">
<strong>Kiln gives you:</strong><br />
• A complete version control system
based on <a href="http://mercurial.selenic.com/" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/flyout/mercurial.selenic.com');">Mercurial</a><br />
• <a href="http://fogcreek.com/kiln/learnmore.html#hist_BranchAndMerge" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/flyout/branchandmerge.kilnhg.com');">Branching and merging</a> that really works
</div>
<div class="flyouttext">
• <a href="http://fogcreek.com/kiln/learnmore.html#hist_Tools" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/flyout/tools.kilnhg.com');">Straightforward setup</a> on your server, or simple secure hosting on ours<br />
• Seamlessly integrated <a href="http://fogcreek.com/kiln/learnmore.html#hist_StartReviewsEffortlessly" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/flyout/startreviews.kilnhg.com');">code review</a>
</div>
<div class="flyouttext"> <a href="convert.html" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/flyout/freetrial.shop.fogcreek.com');"><img src="i/getstarted.gif" width="182" height="24" border="0" /></a>
</div>
<div class="flyoutteaser"><nobr><strong>Try Kiln free!</strong> Mercurial hosting and more.</nobr></div>
</div>
<div class="toptop" align="left">
<ul>
<li align="center"><a href="http://www.joelonsoftware.com/" onClick="javascript: pageTracker._trackPageview('/outbound/toptop/joelonsoftware.com');">Joel on Software</a></li>
<li align="center"><a href="http://mercurial.selenic.com/" onClick="javascript: pageTracker._trackPageview('/outbound/toptop/mercurial.selenic.com');">Mercurial</a></li>
<li align="center"><a href="index.html">Home</a></li>
</ul>
</div>
<div id="dropshadow"></div>
<div id="topnav">
<div class="tInterior">
<a href="index.html">
<img src="i/logo.png" border="0" alt="HgInit Home" />
</a>
Even if you’re working by yourself,
you should use Mercurial to get the
benefits of version control. This tutorial shows
how easy it is to check a directory into Mercurial
so you can track old versions easily.
</div>
</div>
<div class="main">
<h1>Ground up Mercurial</h1>
<div class="content">
<p>
Mercurial is a <em>version control system</em>. Developers use it to manage source code.
It serves two important purposes:
</p>
<ol>
<li>It keeps track of every old version of every file</li>
<li>It can merge different versions of your code, so that teammates can work independently on the code and then merge their changes</li>
</ol>
<p>Without Mercurial, you could try to keep old versions
just by making a lot of copies of the directory containing all your code:</p>
<div class="i">
<img src="i/01-copies.png">
</div>
<p>This is tedious, takes up a lot of disk space, and confusing. Using version control is a better way to do this.</p>
<p>Most people work with Mercurial through the command line, which works on Windows, Unix, and Mac. The command for Mercurial is <strong>hg</strong>:
</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit> <strong>hg</strong>
Mercurial Distributed SCM
basic commands:
add add the specified files on the next commit
annotate show changeset information by line for each file
clone make a copy of an existing repository
commit commit the specified files or all outstanding changes
diff diff repository (or selected files)
export dump the header and diffs for one or more changesets
forget forget the specified files on the next commit
init create a new repository in the given directory
log show revision history of entire repository or files
merge merge working directory with another revision
pull pull changes from the specified source
push push changes to the specified destination
remove remove the specified files on the next commit
serve export the repository via HTTP
status show changed files in the working directory
summary summarize working directory state
update update working directory
use "hg help" for the full list of commands or "hg -v" for details
</pre>
<div class="codebottom"> </div>
</div>
<p>Typing <strong>hg</strong> without anything else gives you a list of the most common commands that are available. You can also try <strong>hg help</strong> for a complete list of commands.</p>
<p>To take advantage of version control, you needed a <em>repository</em>. A repository stores all your old versions of every file. To save disk space, it’s not actually going to store every old version—it’s just going to store a compact list of changes.</p>
<p>In the old days, getting a repository was a big deal. You had to have a central server somewhere and you had to install software on it. Mercurial is <em>distributed</em>, so you can use it without a fancy central server. You can run it entirely on your own computer. And getting a repository is super-easy: you just go into the top-level directory where all your code lives…</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit> <strong>cd CountDown</strong>
c:\hginit\CountDown> <strong>dir /w</strong>
Volume in drive C has no label.
Volume Serial Number is 9862-36C5
Directory of c:\hginit\CountDown
[.] [..] a.txt
AlternateMessages.xml App.config App.xaml
App.xaml.cs CountDown.xaml CountDown.xaml.cs
DevDaysCountDown.csproj favicon.ico [Images]
[Properties] [TweetSharp]
9 File(s) 155,932 bytes
5 Dir(s) 76,083,609,600 bytes free
</pre>
<div class="codebottom"> </div>
</div>
<div class="cheat">
</div>
<p>… there’s my code, and you type <strong>hg init</strong>:</p>
<div class="cheatcontent" style="margin-top:-50px">
<div class="cheattop">
<div class="command">hg init</div>
</div>
<p class="cheattext">creates a repository</p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<div class="codesnippet">
<div class="codetop"> </div>
<pre class="cl">
c:\hginit\CountDown> <strong>hg init</strong>
c:\hginit\CountDown>
</pre>
<div class="codebottom"> </div>
</div>
<p>Wait a minute, did anything happen? It doesn’t look like anything happened. But if you look closely, you’ll see that there’s a new directory there, named <strong>.hg</strong>:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre class="cl">
c:\hginit\CountDown> <strong>dir /w</strong>
Volume in drive C has no label.
Volume Serial Number is 9862-36C5
Directory of c:\hginit\CountDown
[.] [..] [.hg]
a.txt AlternateMessages.xml App.config
App.xaml App.xaml.cs CountDown.xaml
CountDown.xaml.cs DevDaysCountDown.csproj favicon.ico
[Images] [Properties] [TweetSharp]
9 File(s) 155,932 bytes
6 Dir(s) 76,083,650,560 bytes free
</pre>
<div class="codebottom"> </div>
</div>
<p>That’s the repository! It’s a directory full of everything Mercurial needs. Settings, old version of files, tags, an extra pair of socks for when it rains, etc. <em>Don’t go in there.</em> You are almost never going to want to mess with that directory directly.</p>
<p>OK, now that we have a fresh new repository, we’re going to want to add all these source files to it. That’s easy, too: just type <strong>hg add</strong>.</p>
<div class="cheatcontent" style="margin-top:-60px">
<div class="cheattop">
<div class="command">hg add</div>
</div>
<p class="cheattext">schedules files to be added to the repository. They won’t actually be added until you commit </p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg add</strong>
adding AlternateMessages.xml
adding App.config
adding App.xaml
adding App.xaml.cs
adding CountDown.xaml
adding CountDown.xaml.cs
adding DevDaysCountDown.csproj
adding Images\background_city.jpg
adding Images\carsonified_presents.png
adding Images\darkpanel.png
adding Images\devdays.png
adding Images\failwhale.png
adding Images\holding_image.jpg
adding Images\jeff_atwood.jpg
adding Images\joel_spolsky.jpg
adding Images\logo_stackoverflow.png
adding Images\matt_lacey.jpg
adding Images\sideDarkpanel.png
adding Images\vertical_lines2.png
adding Properties\AssemblyInfo.cs
adding Properties\Resources.Designer.cs
adding Properties\Resources.resx
adding Properties\Settings.Designer.cs
adding Properties\Settings.settings
adding TweetSharp\Dimebrain.TweetSharp.dll
adding TweetSharp\Dimebrain.TweetSharp.xml
adding TweetSharp\Newtonsoft.Json.dll
adding a.txt
adding favicon.ico
</pre>
<div class="codebottom"> </div>
</div>
<p>There’s still one more step… you have to <em>commit</em> your changes. What changes? The change of adding all those files.</p>
<p>Why do you have to commit? With Mercurial, committing says “hey, the way the files look right now—please remember that.” It’s like making a copy of the whole directory… every time you have something that you’ve changed that you sorta like, you commit.</p>
<!-- hg commit box -->
<div class="cheatcontent" style="margin-top:-80px">
<div class="cheattop">
<div class="command">hg commit</div>
</div>
<p class="cheattext">saves the current state of all files to the repository </p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg commit</strong>
</pre>
<div class="codebottom"> </div>
</div>
<p>Mercurial will pop up an editor so that you can type a commit message. This is just something you type to remind yourself of what changed in this commit.</p>
<img src="i/01-commit0.png">
<p>When you save and exit, your files will be committed.</p>
<p>You can type <strong>hg log</strong> to see a history of changes. It’s like your repository’s blog:</p>
<!-- hg log box -->
<div class="cheatcontent" style="margin-top:-50px">
<div class="cheattop">
<div class="command">hg log</div>
</div>
<p class="cheattext">shows the history of changes committed to the repository </p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg log</strong>
changeset: 0:da5f372c3901
tag: tip
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:04:30 2010 -0500
summary: Initial version of the CountDown code</pre>
<div class="codebottom"> </div>
</div>
<p>Let’s edit a file and see what happens.</p>
<!-- edit text file module -->
<div class="edit1">
<div class="edittopbefore">
a.txt </div>
<div class="editcontent">
Scott Adams: Normal people believe that if it ain't
broke, don't fix it. Engineers believe that if it
ain't broke, it doesn't have enough features yet.
</div>
<img src="i/edit-bot.gif" width="387" height="76" />
</div>
<div class="edit2">
<img src="i/arrow2.gif" width="83" height="97" class="editArrow" />
<div class="edittopafter">
a.txt
</div>
<div class="editcontent">
<strong>SCOTT ADAMS:</strong>
Normal people believe that if it ain't
broke, don't fix it. Engineers believe that if it
ain't broke, it doesn't have enough features yet.
</div>
<img src="i/edit-bot.gif" width="387" height="76" />
</div>
<div style="clear: both;"> </div>
<!-- end edit text file module -->
<p>Now that we’ve made another change, we can commit it using <strong>hg commit</strong>:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg commit</strong>
</pre>
<div class="codebottom"> </div>
</div>
<p>Notice that Mercurial has figured out that only one file, a.txt, changed:</p>
<img src="i/01-commit1.png">
<p>And now that I’ve committed, let’s take a look at the log:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg log</strong>
changeset: 1:a9497f468dc3
tag: tip
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:26:13 2010 -0500
summary: Capitalized "Scott Adams"
changeset: 0:da5f372c3901
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:04:30 2010 -0500
summary: Initial version of the CountDown code
</pre>
<div class="codebottom"> </div>
</div>
<p>Like any modern blogger, Mercurial puts the newest stuff on top.</p>
<p>I’m going to make one more change, just to amuse myself.</p>
<div class="edit1">
<div class="edittopbefore">
a.txt </div>
<div class="editcontent">
SCOTT ADAMS: Normal people believe that if it ain't
broke, don't fix it. Engineers believe that if it
ain't broke, it doesn't have enough features yet.
</div>
<img src="i/edit-bot.gif" width="387" height="76" />
</div>
<div class="edit2">
<img src="i/arrow2.gif" width="83" height="97" class="editArrow" />
<div class="edittopafter">a.txt</div>
<div class="editcontent">
SCOTT ADAMS:
Normal people believe that if it <strong>isn't
broken</strong>, don't fix it. Engineers believe that if it
<strong>isn't broken</strong>, it doesn't have enough features yet.
</div>
<img src="i/edit-bot.gif" width="387" height="76" />
</div>
<div style="clear: both;"> </div>
<p>Committing:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg commit</strong>
</pre>
<div class="codebottom"> </div>
</div>
<p>My commit message:</p>
<img src="i/01-commit2.png">
<p>And now what does the log show?</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg log</strong>
changeset: 2:55490459b740
tag: tip
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:47:43 2010 -0500
summary: Fixed some grammar
changeset: 1:a9497f468dc3
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:26:13 2010 -0500
summary: Capitalized "Scott Adams"
changeset: 0:da5f372c3901
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:04:30 2010 -0500
summary: Initial version of the CountDown code
</pre>
<div class="codebottom"> </div>
</div>
<p>OK, that was a lot of fun. I made some changes, and each time
I made a significant change, I committed it to the repository.</p>
<p>I know what you’re thinking. You’re thinking, “JOEL, THIS ALL SEEMS LIKE A BIG WASTE OF TIME.”
Why go through all this rigamarole of committing?
</p>
<p>Patience, young grasshopper. You’re about to learn how to get some benefit out of this.</p>
<p>Number one. Let’s say you make a huge mistake editing.</p>
<!-- edit text file module -->
<div class="edit1">
<div class="edittopbefore">
a.txt </div>
<div class="editcontent">
SCOTT ADAMS: Normal people believe that if it isn't
broken, don't fix it. Engineers believe that if it
isn't broken, it doesn't have enough features yet.
</div>
<img src="i/edit-bot.gif" width="387" height="76" />
</div>
<div class="edit2">
<img src="i/arrow2.gif" width="83" height="97" class="editArrow" />
<div class="edittopafter">a.txt</div>
<div class="editcontent">
<strong>DAN QUAYLE: Illegitimacy is something we should
talk about in terms of not having it.</strong>
</div>
<img src="i/edit-bot.gif" width="387" height="76" />
</div>
<div style="clear: both;"> </div>
<!-- end edit text file module -->
<p>And then, gosh, just for good measure you delete a couple of
really important files.</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>del favicon.ico</strong>
c:\hginit\CountDown> <strong>del App.xaml</strong>
</pre>
<div class="codebottom"> </div>
</div>
<p>In the days before Mercurial, this would be a good opportunity to go crying
to the system administrator and asking piercingly sad questions about
<em>why</em> the backup system is “temporarily” out of commission and has been
for the last eight months.</p>
<p>The system administrator, whom everybody calls Taco, is too shy to eat lunch
with the rest of the team. On those rare occasions where he is away from his swivel office
chair, you will notice a triangular-shaped salsa-colored stain on the seat where
drippings of his many Mexican lunches fell between his legs, insuring that nobody takes
his chair, even though it is the superior Herman Miller variety that the company founders bought
themselves, not the standard-issue Staples $99 special that causes everyone else
back pain.</p>
<p>Anyway, yeah, there’s no backup.</p>
<p>Thanks to Mercurial, though, when you’re unhappy with your changes, you can just issue
the handy command <strong>hg revert</strong> which will immediately revert
your directory back to the way it was at the time of the last commit.</p>
<!-- hg log box -->
<div class="cheatcontent" style="margin-top:-80px">
<div class="cheattop">
<div class="command">hg revert</div>
</div>
<p class="cheattext">revert changed files back to committed version </p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg revert --all</strong>
reverting App.xaml
reverting a.txt
reverting favicon.ico
c:\hginit\CountDown> <strong>type a.txt</strong>
SCOTT ADAMS: Normal people believe that if it isn't
broken, don't fix it. Engineers believe that if it
isn't broken, it doesn't have enough features yet.
</pre>
<div class="codebottom"> </div>
</div>
<p>I used the command line argument <strong><code>--</code>all</strong> because I wanted
to revert <em>all</em> files back to their original state.</p>
<p>So, when you’re working on source code with Mercurial:</p>
<ol>
<li>Make some changes</li>
<li>See if they work</li>
<li>If they do, <strong>commit</strong> them</li>
<li>If they don’t, <strong>revert</strong> them</li>
<li>GOTO 1</li>
</ol>
<p>(I know. Between the Windows command prompt and the GOTO statements, I am the <em>least cool programmer</em> who ever lived.)</p>
<!-- hg log box -->
<div class="cheatcontent" style="margin-top:-10px">
<div class="cheattop">
<div class="command">hg status</div>
</div>
<p class="cheattext">shows a list of changed files</p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<p>As time goes on, you may get confused about where you are and what
changes you’ve made since the last commit. Mercurial keeps
track of all that for you. All you have to do is type <strong>hg status</strong> and
Mercurial will give you a list of files that have changed.</p>
<p>Suppose I create a file, edit a file, and delete a file.</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>copy a.txt b.txt</strong>
1 file(s) copied.
c:\hginit\CountDown> <strong>notepad2 a.txt</strong>
c:\hginit\CountDown> <strong>del favicon.ico</strong>
c:\hginit\CountDown> <strong>hg status</strong>
M a.txt
! favicon.ico
? b.txt
</pre>
<div class="codebottom"> </div>
</div>
<p><strong>hg status</strong> lists any files that have changed with a little letter at
the beginning of the line telling you what’s up. “M” means “Modified”—the file has been changed. “!” means missing—the file is supposed to be there, but it disappeared.
“?” means unknown—Mercurial doesn’t know anything about this file. Yet.</p>
<p>Let’s deal with these changes one at a time. That modified file, <strong>a.txt</strong>.
What’s modified about it? You may have forgotten what you changed! Heck, I can
barely even remember what I ate for breakfast most days. Which is especially worrisome
because it’s ALWAYS CHEERIOS. Anyway, a.txt has changed. What changed?</p>
<p>There’s a command for that: <strong>hg diff</strong> tells you exactly what’s changed
with a file since the last commit.</p>
<div class="cheatcontent" style="margin-top:-50px">
<div class="cheattop">
<div class="command">hg diff</div>
</div>
<p class="cheattext">shows what changed in a file </p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>c:\hginit\CountDown> <strong>hg diff a.txt</strong>
diff -r 55490459b740 a.txt
--- a/a.txt Fri Feb 05 13:47:43 2010 -0500
+++ b/a.txt Fri Feb 05 14:31:18 2010 -0500
@@ -1,3 +1,3 @@
-SCOTT ADAMS: Normal people believe that if it isn't
+SCOTT ADAMS: Civilians believe that if it isn't
broken, don't fix it. Engineers believe that if it
isn't broken, it doesn't have enough features yet.
</pre>
<div class="codebottom"> </div>
</div>
<p>This format is a little bit cryptic, but the interesting part
is that you can see some lines that begin with a minus,
which were removed, and lines that begin with a plus, which
were added, so you can see here that “Normal people” was edited to be “Civilians”.
</p>
<!-- hg log box -->
<div class="cheatcontent" style="margin-top:-10px;">
<div class="cheattop">
<div class="command">hg remove</div>
</div>
<p class="cheattext">schedules files to be removed from
the repository. They won’t actually
be removed until you commit. </p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<p>
Now. That missing file, favicon.ico. As earlier, if you didn’t mean to
delete it, you can <strong>hg revert</strong>, but let’s assume you really did mean
to remove it. Whenever you remove (or add) a file, you have to tell Mercurial:
</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg remove favicon.ico</strong>
c:\hginit\CountDown> <strong>hg status</strong>
M a.txt
R favicon.ico
? b.txt
</pre>
<div class="codebottom"> </div>
</div>
<p>The “R” means “Removed” so the next time we commit in Mercurial this file will be
removed. (The <em>history</em> of the file will remain in the repository, so of course
we can always get it back). Finally, we need to add that new file, <strong>b.txt</strong>:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg add</strong>
adding b.txt
c:\hginit\CountDown> <strong>hg st</strong>
M a.txt
A b.txt
R favicon.ico
</pre>
<div class="codebottom"> </div>
</div>
<p>“A” means “Added.” Did you notice I was getting lazy about typing out
<strong>hg status</strong> all the time? Mercurial only needs enough letters
to disambiguate, and there are no other commands that start with <strong>st</strong>.</p>
<p>Having solved all the little ?’s and !’s, I can go ahead and check in my changes:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg commit</strong>
c:\hginit\CountDown> <strong>hg log</strong>
changeset: 3:2f4718ee168e
tag: tip
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 14:54:45 2010 -0500
summary: A few highly meaningful changes. No favicon.ico no more.
changeset: 2:55490459b740
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:47:43 2010 -0500
summary: Fixed some grammar
changeset: 1:a9497f468dc3
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:26:13 2010 -0500
summary: Capitalized "Scott Adams"
changeset: 0:da5f372c3901
user: Joel Spolsky <joel@joelonsoftware.com>
date: Fri Feb 05 13:04:30 2010 -0500
summary: Initial version of the CountDown code</pre>
</pre>
<div class="codebottom"> </div>
</div>
<p>One more thing about the output from
<strong>hg log</strong>: the <em>changeset</em> line shows us a number
to every commit…. actually two numbers: a handy, short one, like “0” for
your initial revision, etc., and a long, goofy hexadecimal one which you can
ignore for now.</p>
<p>Remember that Mercurial keeps, in the repository, enough information
to reconstruct any old version of any file.</p>
<!-- hg log box -->
<div class="cheatcontent" style="margin-top:-10px">
<div class="cheattop">
<div class="command">hg cat</div>
</div>
<p class="cheattext">shows any revision of any file.</p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<p>First of all, the simple command <strong>hg cat</strong> can be used to print any old version
of a file. For example, to see what a.txt looks like now:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg cat a.txt</strong>
SCOTT ADAMS: Civilians believe that if it isn't
broken, don't fix it. Engineers believe that if it
isn't broken, it doesn't have enough features yet.
</pre>
<div class="codebottom"> </div>
</div>
<p>To see what it looked like in the past, I can just pick a changeset number
from the log. Then I use the <strong>cat</strong> command
with the <strong>-r</strong> (“revision”) argument:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg cat -r 0 a.txt</strong>
Scott Adams: Normal people believe that if it ain't
broke, don't fix it. Engineers believe that if it
ain't broke, it doesn't have enough features yet.
</pre>
<div class="codebottom"> </div>
</div>
<p>If the file is long and complicated, and only a little bit of it changed,
I can use the <strong>hg diff</strong> command with an <strong>-r</strong>
argument to print the difference between any two revisions. For example, to see
what changed between revisions 0 and 1:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg diff -r 0:1 a.txt</strong>
diff -r da5f372c3901 -r a9497f468dc3 a.txt
--- a/a.txt Fri Feb 05 13:04:30 2010 -0500
+++ b/a.txt Fri Feb 05 13:26:13 2010 -0500
@@ -1,3 +1,3 @@
-Scott Adams: Normal people believe that if it ain't
+SCOTT ADAMS: Normal people believe that if it ain't
broke, don't fix it. Engineers believe that if it
ain't broke, it doesn't have enough features yet.
</pre>
<div class="codebottom"> </div>
</div>
<p>Finally, if you haven’t collapsed yet from exhaustion, before
I finish this tutorial, I just want to show you <em>one more tiny thing:</em> you can use
the <strong>hg update</strong> command to go backwards or forwards in time
to any revision you want. Well, you can’t really go into the
future <em>per se</em>, although that would be super-cool. If you only had four revisions
you would just <strong>hg update -r 103994</strong> and get some really
cool anti-gravity sci-fi futuristic version of your source code.
But of course, that is not possible.</p>
<!-- hg log box -->
<div class="cheatcontent" style="margin-top:-120px">
<div class="cheattop">
<div class="command">hg update</div>
</div>
<p class="cheattext">update the working directory to a particular revision </p>
<img src="i/cheatbot.png" width="241" height="41" />
</div>
<p>What is possible is going <em>back</em> to any version. Watch:</p>
<div class="codesnippet">
<div class="codetop"> </div>
<pre>
c:\hginit\CountDown> <strong>hg update -r 0</strong>
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
c:\hginit\CountDown> <strong>type a.txt</strong>
Scott Adams: Normal people believe that if it ain't
broke, don't fix it. Engineers believe that if it
ain't broke, it doesn't have enough features yet.
c:\hginit\CountDown> <strong>hg up -r 1</strong>
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
c:\hginit\CountDown> <strong>type a.txt</strong>
SCOTT ADAMS: Normal people believe that if it ain't
broke, don't fix it. Engineers believe that if it
ain't broke, it doesn't have enough features yet.
c:\hginit\CountDown> <strong>hg up</strong>
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
c:\hginit\CountDown> <strong>type a.txt</strong>
SCOTT ADAMS: Civilians believe that if it isn't
broken, don't fix it. Engineers believe that if it
isn't broken, it doesn't have enough features yet.
</pre>
<div class="codebottom"> </div>
</div>
<p><strong>hg update</strong> is actually modifying every file in the directory that changed
to go backwards and forwards through time. If a file was added or removed, it adds or removes it.
Without any arguments, <strong>hg update</strong> goes to the latest version.</p>
<h2>Test yourself</h2>
<p>OK! That’s it for tutorial one. Here’s all the things you should know how to do now:</p>
<ol>
<li>Create a repository</li>
<li>Add and remove files in a repository</li>
<li>After making changes, see what uncommitted changes you made, then</li>
<li>… commit if you like them,</li>
<li>… or revert if you don’t.</li>
<li>See old versions of files, or even move your directory backwards and forwards in time</li>
</ol>
<div class="footer">
<div class="footernav" id="home" align="center"><a href="index.html"><span class="angleQuote">«</span> Home</a></div>
<div class="footernav" id="comingup">
Next, we’ll see how to get your whole team working with Mercurial.</div>
<div class="footernav" id="next" align="center"><a href="02.html">Next <span class="angleQuote">»</span></a></div>
</div>
<div class="pagebottom">
<div class="bottomimg">
<a href="http://www.kilnhg.com" target="_blank" id="logoLink" title="KilnHg.com" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/klinhg.com');"> </a>
<div class="bottomtext">This tutorial was brought to you by the fine folks at Fog Creek Software, makers of Kiln, a version control system powered by Mercurial</div>
<div class="bottomtext"><strong>Kiln gives you:</strong><br />
• A complete version control system based on <a href="http://mercurial.selenic.com/" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/mercurial.selenic.com');">Mercurial</a><br />
• <a href="http://fogcreek.com/kiln/learnmore.html#hist_BranchAndMerge" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/branchandmerge.kilnhg.com');">Branching and merging</a> that really works<br />
• <a href="http://fogcreek.com/kiln/learnmore.html#hist_Tools" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/tools.kilnhg.com');">Straightforward setup</a> on your server, or simple secure hosting on ours<br />
• Seamlessly integrated <a href="http://fogcreek.com/kiln/learnmore.html#hist_StartReviewsEffortlessly" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/startreviews.kilnhg.com');">code review</a><br />
</div>
<div class="bottomtext getStarted">
<a href="convert.html" target="_blank" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/freetrial.shop.fogcreek.com');"><img src="i/getstarted.gif" width="182" height="24" border="0" /></a>
</div>
</div>
<div class="about">
<p>
<strong>Any questions?</strong>
</p>
<p>
If you have any questions about the material in this tutorial,
no matter how newbie, ask them at <a href="http://kiln.stackexchange.com/" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/kiln.stackexchange.com');">the
Kiln Knowledge Exchange.</a>
</p>
<p>
<strong>About the author.</strong>
</p>
<p>
Joel Spolsky is the founder of <a href="http://fogcreek.com" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/fogcreek.com');">Fog Creek Software</a>, a New York company that proves that you can treat programmers well and still be profitable. Programmers get private offices, free lunch, and work 40 hours a week. Customers only pay for software if they’re delighted. Fog Creek makes <a href="http://www.fogbugz.com" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/fogbugz.com');">FogBugz</a>, <a href="http://www.kilnhg.com/" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/text.kilnhg.com');">Kiln</a>, and <a href="https://www.copilot.com/" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/copilot.com');">Fog Creek Copilot</a>. Joel's blog <a href="http://www.joelonsoftware.com/" onClick="javascript: pageTracker._trackPageview('/outbound/bottom/joelonsoftware.com');">Joel on Software</a> is read by programmers everywhere.
</p>
</div>
<!-- close bottom div -->
</div>
<!-- close "content" column -->
</div>
<!-- close "main" div -->
</div>
<!-- bottom grey bar -->
<div class="botbot" align="left">
</div>
<!-- Google Website Optimizer Tracking Script -->
<script type="text/javascript">
if(typeof(_gat)!='object')document.write('<sc'+'ript src="http'+
(document.location.protocol=='https:'?'s://ssl':'://www')+
'.google-analytics.com/ga.js"></sc'+'ript>')</script>
<script type="text/javascript">
try {
var gwoTracker=_gat._getTracker("UA-225715-15");
gwoTracker._trackPageview("/2687020024/test");
}catch(err){}</script>
<!-- End of Google Website Optimizer Tracking Script -->
</body>
</html>
|
Loading...