partial test for special case of reach 1 unconnected

[wkitlasten]

I have added test_sfr_connections() to test_mf6.py. It uses external files added to examples/data/sfr_test/ which define the package and connection data.

The model that uses examples/data/sfr_test/mf6_sfr0_* has the last two reaches unconnected . MF6 runs with a mild warning and flopy loads the model fine.

The model that uses examples/data/sfr_test/mf6_sfr1_* has the first reach unconnected. MF6 runs with the same warning but flopy fails to load the model with the following warning, seemingly unrelated to the first reach:

loading simulation...
  loading simulation name file...
  loading tdis package...
  loading model gwf6...
    loading package dis...
    loading package ic...
    loading package npf...
    loading package sfr...
Traceback (most recent call last):
  File "C:\modelling\flopy\flopy\mf6\data\mffileaccess.py", line 1477, in read_list_data_from_file
    data_line=data_line,
  File "C:\modelling\flopy\flopy\mf6\data\mffileaccess.py", line 1893, in load_list_line
    zero_based=zero_based,
  File "C:\modelling\flopy\flopy\mf6\data\mffileaccess.py", line 2199, in _append_data_list
    sub_amt=sub_amt,
  File "C:\modelling\flopy\flopy\mf6\data\mfdatautil.py", line 107, in convert_data
    return int(PyListUtil.clean_numeric(data)) - sub_amt
ValueError: invalid literal for int() with base 10: '17 16 -18'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\modelling\flopy\flopy\mf6\mfpackage.py", line 896, in load
    external_file_info,
  File "C:\modelling\flopy\flopy\mf6\data\mfdatalist.py", line 1341, in load
    first_line, file_handle, storage, pre_data_comments
  File "C:\modelling\flopy\flopy\mf6\data\mffileaccess.py", line 1158, in load_from_package
    self._data_line,
  File "C:\modelling\flopy\flopy\mf6\data\mffileaccess.py", line 1497, in read_list_data_from_file
    ex,
flopy.mf6.mfbase.MFDataException: An error occurred in data element "connectiondata" model "gwf6" package "sfr". The error occurred while loading data list from package file in the "read_list_data_from_file" method.
Additional Information:
(1) Unable to process line 17 of data list: "17 16 -18
"

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\modelling\flopy\autotest\test_mf6.py", line 1091, in test_sfr_connections
    sim2 = MFSimulation.load(sim_ws=str(tmpdir))
  File "C:\modelling\flopy\flopy\mf6\modflow\mfsimulation.py", line 719, in load
    load_only,
  File "C:\modelling\flopy\flopy\mf6\modflow\mfgwf.py", line 137, in load
    load_only,
  File "C:\modelling\flopy\flopy\mf6\mfmodel.py", line 805, in load_base
    instance.load_package(ftype, fname, pname, strict, None)
  File "C:\modelling\flopy\flopy\mf6\mfmodel.py", line 1858, in load_package
    package.load(strict)
  File "C:\modelling\flopy\flopy\mf6\mfpackage.py", line 2639, in load
    self._load_blocks(fd_input_file, strict)
  File "C:\modelling\flopy\flopy\mf6\mfpackage.py", line 2817, in _load_blocks
    block_header_info, fd_input_file, strict
  File "C:\modelling\flopy\flopy\mf6\mfpackage.py", line 908, in load
    fd_block.name,
flopy.mf6.mfbase.MFDataException: An error occurred in data element "connectiondata" model "test_sfr" package "sfr". The error occurred while loading data list from package file in the "read_list_data_from_file" method.
Additional Information:
(1) Unable to process line 17 of data list: "17 16 -18
"
(2) Error occurred while loading data "connectiondata" in block "connectiondata" from file "C:\modelling\flopy\autotest\.\../examples/data/sfr_test/mf6_sfr1_connection.txt".

Admittedly this is a "special" case and I am struggling to piece together the testing structure (I'm new to testing, sorry). But hopefully this gives enough for someone to go on? @mwtoews , @emorway-usgs ?

[codecov]

Codecov Report

Merging #1635 (071eb19) into develop (f017c0d) will decrease coverage by 41.8%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           develop   #1635      +/-   ##
==========================================
- Coverage     71.8%   30.1%   -41.8%     
==========================================
  Files          253     253              
  Lines        55887   54388    -1499     
==========================================
- Hits         40178   16395   -23783     
- Misses       15709   37993   +22284     

Impacted Files	Coverage Δ
flopy/mfusg/mfusgsms.py	6.1% <0.0%> (-92.0%)	⬇️
flopy/mf6/utils/postprocessing.py	9.2% <0.0%> (-88.9%)	⬇️
flopy/seawat/swtvdf.py	8.0% <0.0%> (-88.5%)	⬇️
flopy/modflow/mfevt.py	7.5% <0.0%> (-87.5%)	⬇️
flopy/utils/mtlistfile.py	4.6% <0.0%> (-85.4%)	⬇️
flopy/mf6/utils/lakpak_utils.py	2.0% <0.0%> (-85.4%)	⬇️
flopy/modflow/mfhyd.py	13.2% <0.0%> (-85.2%)	⬇️
flopy/utils/swroutputfile.py	10.7% <0.0%> (-85.1%)	⬇️
flopy/modflow/mfag.py	7.2% <0.0%> (-83.9%)	⬇️
flopy/modflow/mfhob.py	5.9% <0.0%> (-83.1%)	⬇️
... and 207 more