path: root/english/devel/testing.wml

#use wml::debian::template title="Debian “testing” distribution" BARETITLE=true
#include "$(ENGLISHDIR)/releases/info"

<p>For basic, user-oriented information about the testing distribution,
please see <a href="$(DOC)/manuals/debian-faq/ftparchives#testing">the Debian FAQ</a>.</p>

<p>An important thing to note, both for regular users and the developers of
testing, is that security updates for testing are <strong>not managed by
the security team</strong>. For more information please see the
<a href="../security/faq#testing">Security Team's FAQ</a>.</p>

<p>This page primarily covers the aspects of <q>testing</q> important to Debian
developers.</p>

<h2>How <q>testing</q> works</h2>

<p>The <q>testing</q> distribution is an automatically generated distribution.
It is generated from the <q>unstable</q> distribution by a set of scripts which
attempt to move over packages which are reasonably likely to lack release-critical
bugs. They do so in a way that ensures that dependencies of other packages
in testing are always satisfiable.</p>

<p>A (particular version of a) package will move into testing when it
satisfies all of the following criteria:</p>

<ol>
  <li>It must have been in unstable for 10, 5 or 2 days, depending on the
  urgency of the upload;</li>

  <li>It must be compiled and up to date on all architectures it has
  previously been compiled for in unstable;</li>

  <li>It must not have release-critical bugs which do not also apply to
  the version currently in <q>testing</q> (see below for
  <a href="#faq">more information</a>);</li>

  <li>All of its dependencies must <em>either</em> be satisfiable by
  packages already in <q>testing</q>, <em>or</em> be satisfiable by the group
  of packages which are going to be installed at the same time;</li>

  <li>The operation of installing the package into <q>testing</q> must not break
  any packages currently in <q>testing</q>. (See below for
  <a href="#faq">more information</a>.)</li>
</ol>

<p>A package which satisfies the first three of the above is said to be a
<q>Valid Candidate</q>.</p>

<p>The update script shows when each package might move from <q>unstable</q> into
<q>testing</q>. The output is twofold:</p>

<ul>
  <li>The <a href="https://release.debian.org/britney/update_excuses.html">\
      update excuses</a>
      [<a href="https://release.debian.org/britney/update_excuses.html.gz">\
      gzipped</a>]:
      list of all candidate package versions and the basic status of their
      propagation into <q>testing</q>; this is somewhat shorter and nicer than
  </li>
  <li>The <a href="https://release.debian.org/britney/update_output.txt">\
      update output</a>
      [<a href="https://release.debian.org/britney/update_output.txt.gz">\
      gzipped</a>]:
      the complete, rather crude output of the <q>testing</q> scripts as they
      recurse through the candidates
  </li>
</ul>

<h2><a name="faq">Frequently Asked/Answered Questions</a></h2>

# Note to translators: these two first items are almost the same as
# https://www.debian.org/doc/manuals/developers-reference/pkgs.html#faq

<h3><q>What are release-critical bugs, and how do they get counted?</q></h3>

<p>All bugs of some higher severities are by default considered
<em><a href="https://bugs.debian.org/release-critical/">release-critical</a></em>;
currently, these are <strong>critical</strong>, <strong>grave</strong> and
<strong>serious</strong> bugs.</p>

<p>Such bugs are presumed to have an impact on the chances that the package
will be released with the stable release of Debian: in general, if a package
has open release-critical bugs filed on it, it won't get into <q>testing</q>, and
consequently won't be released in <q>stable</q>.</p>

<p>
The <q>testing</q> bug count are all release-critical bugs which
are marked to apply to <tt>package/version</tt> combinations
that are available in <q>testing</q>for a release architecture.
</p>


<h3><q>How could installing a package into <q>testing</q> possibly break other
packages?</q></h3>

<p>The structure of the distribution archives is such that they can only
contain one version of a package; a package is defined by its name. So, when
the source package <tt>acmefoo</tt> is installed into <q>testing</q>, along with
its binary packages <tt>acme-foo-bin</tt>, <tt>acme-bar-bin</tt>,
<tt>libacme-foo1</tt> and <tt>libacme-foo-dev</tt>, the old version is
removed.</p>

<p>However, the old version may have provided a binary package with an old
soname of a library, such as <tt>libacme-foo0</tt>. Removing the old
<tt>acmefoo</tt> will remove <tt>libacme-foo0</tt>, which will break any
packages which depend on it.</p>

<p>Evidently, this mainly affects packages which provide changing sets of
binary packages in different versions (in turn, mainly libraries). However,
it will also affect packages upon which versioned dependencies have been
declared of the ==, &lt;= or &lt;&lt; varieties.</p>

<p>When the set of binary packages provided by a source package change in
this way, all the packages that depended on the old binaries will have to be
updated to depend on the new binaries instead. Because installing such a
source package into <q>testing</q> breaks all the packages that depended on it in
<q>testing</q>, some care now has to be taken: all the depending packages must be
updated and ready to be installed themselves so that they won't be broken,
and, once everything is ready, manual intervention by the release manager or
an assistant is normally required.</p>

<p>If you are having problems with complicated groups of packages like this,
contact debian-devel or debian-release for help.</p>

<h3><q>I still don't understand! The <q>testing</q> scripts say that this
package is a valid candidate, but it still hasn't gone into
<q>testing</q>.</q></h3>

<p>This tends to happen when in some way, directly or indirectly, installing
the package will break some other package.</p>

<p>Remember to consider your package's dependencies. Suppose your package
depends on libtool, or libltdl<var>X</var>. Your package won't go into
<q>testing</q> until the right version of libtool is ready to go in with it.</p>

<p>In turn, that won't happen until installing libtool doesn't break things
already in <q>testing</q>. In other words, until all other packages which depend
on libltdl<var>Y</var> (where <var>Y</var> is the earlier version) have been
recompiled, and all their release critical bugs are gone, etc, none of these
packages will enter <q>testing</q>.</p>

<p>This is where the <a href="https://release.debian.org/britney/update_output.txt">\
textual output</a>
[<a href="https://release.debian.org/britney/update_output.txt.gz">gzipped</a>]
is useful: it gives hints (albeit very terse ones) as to which packages
break when a valid candidate is added to <q>testing</q> (see the <a
href="$(DOC)/manuals/developers-reference/pkgs.html#details">\
Developer's Reference for more details</a>).
</p>

<h3><q>Why is it sometimes hard to get <kbd>Architecture: all</kbd> packages
into <q>testing</q>?</q></h3>

<p>If the <kbd>Architecture: all</kbd> package is to be installed, it must
be possible to satisfy its dependencies on <strong>all</strong>
architectures. If it depends on certain packages which only compile on a
limited set of Debian's architectures, then it can't do that.</p>

<p>However, for the time being, <q>testing</q> will ignore <kbd>Architecture:
all</kbd> packages' installability on non-i386 architectures. (<q>It's a
gross hack and I'm not really happy to have made it, but there you go.</q>
&mdash;aj)</p>

<h3><q>My package is stalled because it's out of date on some architecture.
What do I do?</q></h3>

<p>Check the status of your package in the
<a href="https://buildd.debian.org/build.php">build log database</a>.
If the package doesn't build, it will be marked as <em>failed</em>;
investigate the build logs and fix any of the problems that are caused
by your package's sources.</p>

<p>If you happen to notice that some architectures have built the new
version of your package, but it isn't showing up in <q>testing</q> scripts output,
then you just have to be a bit more patient until the respective buildd
maintainer uploads the files to the Debian archive.</p>

<p>If you notice that some architectures haven't built your new version of
the package at all, despite the fact you uploaded a fix for an earlier
failure, the reason is probably that it's marked as waiting for dependencies
(Dep-Wait). You can also see the list of these so-called
<a href="https://buildd.debian.org/stats/">wanna-build states</a> to make
sure.</p>

<p>These problems usually get fixed eventually, but if you've been waiting
for a longer period of time (say, two weeks or more), notify the respective
port buildd maintainer if such an address is documented on the
<a href="$(HOME)/ports/">port web page</a>, or the mailing list of the
port.</p>

<p>If you have explicitly dropped the architecture from the Architecture list
in the control file, and the package has been built for that architecture
before, you will need to request that the old binary package for this
architecture be removed from the archive before your package can transition to
testing.  You need to file a bug against <q>ftp.debian.org</q> requesting removal of
the dropped architecture's packages from the unstable archive.  Generally the
relevant porting list should be informed as a matter of courtesy.</p>

<h3><q>Are there any exceptions? I'm sure <tt>acmefoo</tt> has just made
it into <q>testing</q> despite not satisfying all of the requirements.</q></h3>

<p>The release manager can override the rules in two ways:</p>

<ul>
  <li>They can decide that the breakage caused by the installation of a new
      library will make things better rather than worse, and let it go in
      along with its flotilla of dependents.</li>
  <li>They can also manually remove packages from <q>testing</q> that would be
      broken, so that new stuff can be installed.</li>
</ul>

<h3><q>Can you provide a real, non-trivial example?</q></h3>

<p>Here's one: when the source package <tt>apache</tt> is installed into
<q>testing</q>, along with its binary packages <tt>apache</tt>,
<tt>apache-common</tt>, <tt>apache-dev</tt> and <tt>apache-doc</tt>, the
old version is removed.</p>

<p>However, all Apache module packages depend on <code>apache-common (&gt;=
<var>something</var>), apache-common (&lt;&lt; <var>something</var>)</code>,
so this change breaks all of those dependencies. Consequently, all Apache
modules need to be recompiled against the new version of Apache in order
for <q>testing</q> to be updated.</p>

<p>Let's elaborate on this a bit further: after all of the modules have been
updated in unstable to work with a new Apache, the <q>testing</q> scripts try
<tt>apache-common</tt> and find out that it breaks all the Apache modules
because they have <code>Depends: apache-common (&lt;&lt; <var>the current
version</var>)</code>, and then try <tt>libapache-<var>foo</var></tt> to find
out that it doesn't install because it has <code>Depends: apache-common (&gt;=
<var>the new version</var>)</code>.</p>

<p>However, later they'll apply a different logic (sometimes prompted by a
manual intervention): they'll ignore the fact <tt>apache-common</tt> breaks
stuff, and keep going with things that work; if it still doesn't work after
we've done everything we can, too bad, but maybe it <strong>will</strong>
work. Later they'll try all the random <tt>libapache-<var>foo</var></tt>
packages and see that they indeed work.</p>

<p>After everything's been tried, they check how many packages have been
broken, work out if that's better or worse than what there was originally
and either accept everything or forget about it. You'll see this in
<tt>update_output.txt</tt> on <q><code>recur:</code></q> lines.</p>

<p>For example:</p>

<pre>
         recur: [<var>foo</var> <var>bar</var>] <var>baz</var>
</pre>

<p>basically says <q>having already found that <var>foo</var> and
<var>bar</var> make things better, I'm now trying <var>baz</var> to
see what happens, even though that breaks things</q>. The lines of
<tt>update_output.txt</tt> that start with <q><code>accepted</code></q> indicate
things that appear to make things better, and <q><code>skipped</code></q> lines make
things worse.</p>

<h3><q>The <tt>update_output.txt</tt> file is completely unreadable!</q></h3>

<p>That is not a question. ;-)</p>

<p>Let's take an example:</p>

<pre>
 skipped: cln (0) (150+4)
     got: 167+0: a-40:a-33:h-49:i-45
     * i386: ginac-cint, libginac-dev
</pre>

<p>This means that if <tt>cln</tt> goes into <q>testing</q>, <tt>ginac-cint</tt>
and <tt>libginac-dev</tt> become uninstallable in <q>testing</q> on i386.
Note that the architectures are checked in alphabetical order and only the
problems on the first architecture with problems are shown &mdash; that's why
the alpha architecture is shown so often.</p>

<p>The <q>got</q> line includes the number of problems in <q>testing</q> on the
different architectures (until the first architecture where a problem is
found &mdash; see above). The <q>i-45</q> means that if <tt>cln</tt> would go into
<q>testing</q>, there would be 45 uninstallable packages on i386. Some of the
entries above and below <tt>cln</tt> show there were 43 uninstallable
packages in <q>testing</q> on i386 at the time.</p>

<p>The <q>skipped: cln (0) (150+4)</q> line means that there are still 150
packages to go through after this package until this check of all packages
is completed, and that 4 packages have been found already that won't be
planned to be upgraded because they would break dependencies. The <q>(0)</q> is
irrelevant, you can safely ignore it.</p>

<p>Note that there are several checks of all packages in one <q>testing</q>
script run.</p>

<p><em>Jules Bean initially assembled the frequently asked questions and
answers.</em></p>
# Created: Sat Dec  8 12:44:29 GMT 2001

<h2>Additional information</h2>

<p>The following pages provide additional information about the current state
of testing and the migration of packages from unstable to testing:</p>

<ul>
<li>Statistics on binary packages that are out of date for
<a href="https://release.debian.org/britney/testing_outdate.txt">testing</a>,
<a href="https://release.debian.org/britney/stable_outdate.txt">stable</a>
<li>Dependency problems in
<a href="https://qa.debian.org/debcheck.php?list=INDEX&amp;dist=testing">testing</a>,
<a href="https://qa.debian.org/debcheck.php?list=INDEX&amp;dist=stable">stable</a>
</ul>

<p>You might be interested in reading an older
<a href="https://lists.debian.org/debian-devel-0008/msg00906.html">explanation
email</a>. Its only major flaw is that it doesn't take the package pool
into account, because that was implemented by James Troup after it was
written.</p>

<p>The testing code is available from
<a href="https://release.debian.org/britney/update_out_code/">ftp-master</a>.</p>

<p><em>Anthony Towns takes credit for the implementation of testing.</em></p>