Re: [Opengrads-devel] Wgrib2 and autotools

[Arlindo da S. <da...@al...>]

Wes et al,
  I just added a very rudimentary test suite, using PyUnit to organize the
tests. This is similar to what I did for GrADS; I have some notes here:

  http://opengrads.org/wiki/index.php?title=PyTests:_GrADS_Test_Suite

 The wgrib2 implementation is simpler than the one in grads as we only have
one executable (wgrib2) and only one type of input file (grib 2).

 After you build wgrib2, just type

% make check

and it will run all tests.

We need more test cases!!! In principle, each command line option should
have its own unit test.  Right now I have a single test data file (under
data/model_25.grb2) something the Mike Fiorino prepared for me for testing
grads v2. This single file could be used for most if not all test cases.

To add a new test, just add a new python function that starts with "test_"
in file pytests/TestModelFile.py - no other change is required. For example,
to test the -min/-max options I added the function:

    def test_opt_minmax(self):
        result = self.g2('-d 1 -min -max ')
        self.assertEqual(result[0],'1:0:min=10664.5:max=12531.1\n')
        result = self.g2('-d 33 -min -max ')
        self.assertEqual(result[0],'33:322100:min=95073.8:max=104675\n')
        result = self.g2('-d 67 -min -max')
        self.assertEqual(result[0],'67:676013:min=94670.3:max=104569\n')

The statement

        result = self.g2('-d 1 -min -max ')

runs

 ../src/wgrib2 -d 1 -min -max data/model_25.grb2

and captures the result in 'result'. The statement:

        self.assertEqual(result[0],'1:0:min=10664.5:max=12531.1\n')

compares the result with an expected (hard coded) outcome. This receipt can
be used for all the options producing simple ASCII output. For binary files,
one could produce the binary file and check the md5sum against a hardcoded
value, this way keeping the distribution tarball small enough. I can help
with the python wiring of the test cases, but it would be better for people
familiar with wgrib2 (i.e., developers) to come up with the actual tests.

  Take my word for it: a test suite is worth its weight in gold, specially
when porting to a new platform.

  To get the latest wgrib2 sources:

% gacvs co -P Wgrib2

and you should get the new pytests/ directory, including the test data.

   Arlindo

-- 
Arlindo da Silva
da...@al...