AutoQA tests/Depcheck

= What Is Depcheck? = Depcheck was created to detect packages with broken dependencies. As the test matures, it will eventually be a part of the rel-eng process to prevent broken packages from being pushed to the testing or stable package repositories.

= How Does Depcheck Work? = Describing exactly how depcheck functions is outside the scope of this page but the basic idea is to trick yum into thinking that all available packages are installed and attempt to install the package under test. If there are problems installing that package, depcheck assumes that those errors are dependency problems and fails the error-causing package.

For more detailed information on depcheck, there are several blog posts about its internals.

= Understanding Failures =

Missing requirements
Looking at an example log, we see the following highlight: matahari-lib-0.4.1-2.fc14.i686 from pending has depsolving problems --> Package: matahari-lib-0.4.1-2.fc14.i686 (pending) -->    Requires: libsigar.so

In this case, requires the shared library. At the time the test ran, the shared library was not provided by any available package.

"Not Found" errors
Look at the following excerpt: SKIPBROKEN: --> Package: erlang-js-0.5.0-2.fc15.x86_64 (f15) -->    Requires: libjs.so.1(64bit) -->    Removing: js-1.70-13.fc15.x86_64 (f15) -->        libjs.so.1(64bit) -->    Updated By: 1:js-1.8.5-6.fc15.x86_64 (pending) -->        Not found

Build has broken dependencies. It requires  which is provided by. But the package is about to be updated (as part of this or some other update request) to. And the latter build does not provide, thus it is marked as Not found.

Let's confirm: $ repoquery -q --provides js-1.70-13.fc15.x86_64 | grep libjs libjs = 1.70-13.fc15 libjs.so.1(64bit) $ repoquery -q --provides js-1.8.5-6.fc15.x86_64 | grep libjs libjs = 1.8.5-6.fc15

As you can see, by updating the package the dependencies of  would be broken and that it the reason why depcheck rejected this update.

Conflicts
Errors caused by packages conflicting each other should be ignored at the moment. The problem lies in the current implementation of depcheck, in which we 'bend' yum into believing that all the packages are installed at once, and then let it run its depsolver. This means, that if two (or more) packages conflict each other, then yum refuses to install them, and so they get rejected. SKIPBROKEN: 1:grub-0.97-77.fc16.x86_64 from pending has depsolving problems SKIPBROKEN: --> grub conflicts with 1:grub2-1.99-2.fc16.x86_64

= Fixing Failures = Fortunately, the fixes for depcheck errors tend to be relatively straight-forward and tend to fall into one of two categories listed below.

  Problems caused by your package Examine any changes to,   or   in the  file. Ensure correct spelling of all dependencies and confirm that any changed requirements do resolve for the appropriate release. If the dependencies of your package have not changed, it's possible that other packages no longer satisfy the dependencies as expected. Read below for further guidance. The command is helpful to track dependencies.

 Problems caused by other package(s) If your package failed because the dependencies of other packages changed (features they were providing changed or were removed), update the requirements of your package or consult with maintainers of the corresponding packages.



= Other =

Ignored builds
Sometimes, you'll encounter list of "ignored builds" in the report. First of all - do not be alarmed, it is not a wrong state (and we don't mark updates as FAILED if ignored builds occur). The ignored status usually means, that the update was probably changed, and more builds were added, and since we do some 'weird magic' with yum's database of installed packages, these are not recognized as updates, because these were tested in previous runs of Depcheck.

= Getting Help = If you still don't understand why your update failed the test, if you think there's something wrong in our test or its documentation or if you have any other suggestions, please contact us.

= Additional Information =