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Description:

cuppa 0.9.132

A simple, extensible build system for use with
Scons. Cuppa is designed to leverage the
capabilities of Scons, while allowing developers to focus on the task of
describing what needs to be built. In general cuppa supports
make like usage on the command-line. That is developers can simply
write:
scons -D
and have Scons “do the right thing”; building targets for any
sconscript files found in the current directory.
Cuppa can be installed as a normal python package or installed
locally into a site_scons directory allowing it to be effortlessly
integrated into any Scons setup.

Note: -D tells scons to look for an sconstruct file in
the current or in parent directories and if it finds one execute the
sconscript files as if called from that directory. This ensures
everything works as expected. For more details refer to the Scons
documentation

Quick Intro

Get cuppa
The simpest way to get cuppa is to pip install it using:
pip install cuppa

Sample sconstruct file
Let’s look at a minimal sconstruct that makes use of cuppa. It
could look like this:
# Pull in all the Cuppa goodies..
import cuppa

# Call sconscripts to do the work
cuppa.run()
Calling the run method in the cuppa module starts the build
process calling sconscript files.

Sample sconscript file
Here is an example sconscript file that builds all *.cpp files in
the directory where it resides:
Import( 'env' )

# Build all *.cpp source files as executables
for Source in env.GlobFiles('*.cpp'):
env.Build( Source[:-4], Source )
The env.Build() method is provided by cuppa and does essentially
what env.Program() does but in addition is both toolchain and
variant aware, and further can provide notifications on progress.

Note: Source[:-4] simply strips off the file extension .cpp,
that is, the last 4 characters of the file name.

If our sconscript file was for a directory containing *.cpp files
that are actually tests then we could instead write the sconscript
file as:
Import( 'env' )

# Build all *.cpp source files as executables to be run as tests
for Source in env.GlobFiles('*.cpp'):
env.BuildTest( Source[:-4], Source )
The env.BuildTest() method is provided by cuppa and builds the
sources specified as env.Build() does.
However, in addition, passing --test on the command-line will also
result in the executable produced being run by a runner. The default
test runner simply treats each executable as a test case and each
directory or executables as a test suite. If the process executes
cleanly the test passed, if not it failed.
To run this on the command-line we would write:
scons -D --test
If we only want to build and test debug executables we can instead
write this:
scons -D --dbg --test
Or for release only pass --rel.
cuppa also makes it easy to work with dependencies. For example, if
boost was a default dependency for all your
sconscript files you could write your sconstruct file as follows:
import cuppa

cuppa.run(
default_options = {
'boost-home': '<Location of Boost>'
},
default_dependencies = [
'boost'
]
)
This will automatically ensure that necessary includes and other compile
options are set for the boost version that is found at boost-home.
If you need to link against specific boost libraries this can also be
done in the sconscript file as follows:
Import('env')

Test = 'my_complex_test'

Sources = [
Test + '.cpp'
]

env.AppendUnique( STATICLIBS = [
env.BoostStaticLibrary( 'system' ),
env.BoostStaticLibrary( 'log' ),
env.BoostStaticLibrary( 'thread' ),
env.BoostStaticLibrary( 'timer' ),
env.BoostStaticLibrary( 'chrono' ),
env.BoostStaticLibrary( 'filesystem' ),
] )

env.BuildTest( Test, Sources )
The BoostStaticLibrary() method ensures that the library is built in
the correct build variant as required. If you preferred to use dynamic
linking then that can also be achieved using BoostSharedLibrary().
The point is the complexities of using boost
as a dependency are encapsulated and managed separately from the
scontruct and sconscript files allowing developers to focus on intent
not method.

Design Principles
cuppa has been written primarily to provide a clean and structured
way to leverage the power of Scons without the usual problems of hugely
complex scontruct files that diverge between projects. Key goals of
cuppa are:

minimise the need for adding logic into sconscript files, keeping
them as declarative as possible.
allow declarative sconscripts that are both much clearer and
significantly simpler than the equivalent make file, without the
need to learn a whole new scripting language like make or
cmake.
provide a clear structure for extending the facilities offered by
cuppa
provide a clear vocabulary for building projects
codify Scons best practices into cuppa itself so that users just
need to call appropriate methods knowing that cuppa will do the
right thing with their intent
provide a framework that allows experts to focus on providing
facilities for others to use. Write once, use everywhere. For example
one person who knows how best to make
boost available as a dependency can
manage that dependency and allow others to use it seamlessly.

More Details
For more details refer to the project homepage.

Acknowledgements
This work is based on the build system used in
clearpool.io during development of its
next generation exchange platform.