Magics regression test suite

This test suite runs the regression tests for the Magics meteorological plotting package.

Setup the environment

pip install cftime netcdf4 xarray pytest pytest-html
export MAGPLUS_HOME=/path/to/magics
export MAGPLUS_REGRESSION=ON

Running the test suite

pytest --html report.html

A report is created as report.html, showing the visual difference between a reference set of images.
An error is reported if the number of different pixels exceeds a certain threshold.

Creating your own reference dataset

A script can be used to generate the reference dataset for a specific Magics Version:

python make_reference.py

This will generate a png for each test in the reference directory.
You can after that run the test suite using your new Magics version.
This will show you the visual differences between the 2 versions.

Resolving font differences

Different platforms can have different fonts resulting in error threshold being erroneously exceeded. To further lower the chance of false positives, used font aliases can be redefined via the fontconfig configuration file:

cat << EOF > ~/.config/fontconfig/font.conf
<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
    <dir>/path/to/font</dir>
    <match>
        <test name="family">
            <string>sans-serif</string>
        </test>
        <edit name="family" mode="assign" binding="strong">
            <string>FreeSans</string>
        </edit>
    </match>
    <match>
        <test name="family">
            <string>helvetica</string>
        </test>
        <edit name="family" mode="assign" binding="strong">
            <string>FreeSans</string>
        </edit>
    </match>
    <match>
        <test name="family">
            <string>times</string>
        </test>
        <edit name="family" mode="assign" binding="strong">
            <string>FreeSerif</string>
        </edit>
    </match>
</fontconfig>
EOF

Where:

• /path/to/font is the path to custom fonts
• FreeSans is the name of a custom sans serif font
• FreeSerif is the name of a custom serif font

License

Copyright 2019- European Centre for Medium-Range Weather Forecasts (ECMWF).

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.