rpmbuild-order-0.4.0: README.md

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# rpmbuild-order

This package originally based on code from [cabal-sort](http://hackage.haskell.org/package/cabal-sort), sorts rpm package spec files by build order.

    $ rpmbuild-order --help
    $ rpmbuild-order sort mycore mylib myapp
    mylib
    mycore
    myapp

The arguments passed can either be directories containing the package, or spec files.

Using the rpmbuild-order `deps` and `rdeps` commands the ordered
dependencies and reverse dependencies of a package can be obtained
from the current set of checked out package sources.

As of version 0.4, a library is also provided.
See the modules' documentation for details.

## Notes and known problems
1. Given packages A, B, C, where C depends on B, and B depends on A,
and you call

    rpmbuild-order sort C.spec A.spec

then the output may be wrong if C does not have a direct dependency on A.
Even if the order is correct, B is missing in the output
and thus in this case the list of packages cannot be reliably used
for a sequence of builds.

However the `deps` and `rdeps` commands take
other neighbouring package directories into account.

2. repoquery is not used to resolve meta-dependencies or files to packages.
So if a package BuildRequires a file, it will not be resolved to a package.
This may get addressed some day, but file dependencies seem less common for
BuildRequires than Requires.

3. rpmspec is used to parse spec files (for macro expansion etc):
so missing macros packages may lead to erroneous results.