obspy.core.util.testing.ImageComparison¶
-
class
ImageComparison
(image_path, image_name, reltol=1, adjust_tolerance=True, plt_close_all_enter=True, plt_close_all_exit=True, style=None, no_uploads=False, *args, **kwargs)[source]¶ Bases:
obspy.core.util.base.NamedTemporaryFile
Handles the comparison against a baseline image in an image test.
Note
Baseline images are created using matplotlib version 1.3.1.
Parameters: - image_path (str) – Path to directory where the baseline image is located
- image_name (str) – Filename (with suffix, without directory path) of the baseline image
- reltol (float, optional) – Multiplier that is applied to the default tolerance value (i.e. 10 means a 10 times harder to pass test tolerance).
- adjust_tolerance (bool, optional) – Adjust the tolerance based on the matplotlib version. Can optionally be turned off to simply compare two images.
- plt_close_all_enter (bool) – Whether to close all open figures when entering
context (
matplotlib.pyplot.close()
with “all” as first argument. - plt_close_all_exit (bool) – Whether to call
matplotlib.pyplot.close()
with “all” as first argument (close all figures) or no arguments (close active figure). Has no effect ifplt_close=False
. - style (str) – The Matplotlib style to use to generate the figure. When
using matplotlib 1.5 or newer, the default will be
'classic'
to ensure compatibility with older releases. On older releases, the default will leave the style as is. You may wish to set it to'default'
to enable the new style from Matplotlib 2.0, or some alternate style, which will work back to Matplotlib 1.4.0. - no_uploads (bool) – If set to
True
no uploads to imgur are attempted, no matter what (e.g. any options toobspy-runtests
that would normally cause an upload attempt). This can be used to forcibly deactivate upload attempts in image tests that are expected to fail.
The class should be used with Python’s “with” statement. When setting up, the matplotlib rcdefaults are set to ensure consistent image testing. After the plotting is completed, the
ImageComparison.compare()
method is called automatically at the end of the “with” block, comparing against the previously specified baseline image. This raises an exception (if the test fails) with the message string frommatplotlib.testing.compare.compare_images()
. Afterwards all temporary files are deleted automatically.Note
If images created during the testrun should be kept after the test, set environment variable OBSPY_KEEP_IMAGES to any value before executing the test (e.g. with $ OBSPY_KEEP_IMAGES= obspy-runtests or $ OBSPY_KEEP_IMAGES= python test_sometest.py). For obspy-runtests the option “–keep-images” can also be used instead of setting an environment variable. Created images and diffs for failing tests are then stored in a subfolder “testrun” under the baseline image’s directory. To only keep failed images and the corresponding diff image, additionally set environment variable OBSPY_KEEP_ONLY_FAILED_IMAGES to any value before executing the test.
Example
>>> from obspy import read >>> with ImageComparison("/my/baseline/folder", 'plot.png') as ic: ... st = read() # doctest: +SKIP ... st.plot(outfile=ic.name) # doctest: +SKIP ... # image is compared against baseline image automatically
Attributes
__abstractmethods__
__dict__
__doc__
__module__
closed
Public Methods
close
Flush and close the IO object. compare
Run a custom version of matplotlib.testing.compare.compare_images()
and raise an unittest.TestCase.failureException with the message string given by matplotlib if the comparison exceeds the allowed tolerance.detach
Disconnect this buffer from its underlying raw stream and return it. fileno
Returns underlying file descriptor if one exists. flush
Flush write buffers, if applicable. isatty
Return whether this is an ‘interactive’ stream. read
Read and return up to n bytes. read1
Read and return up to n bytes, with at most one read() call to the underlying raw stream. readable
Return whether object was opened for reading. readinto
readinto1
readline
Read and return a line from the stream. readlines
Return a list of lines from the stream. seek
Change stream position. seekable
Return whether object supports random access. tell
Return current stream position. truncate
Truncate file to size bytes. writable
Return whether object was opened for writing. write
Write the given buffer to the IO stream. writelines
Private Methods
Warning
Private methods are mainly for internal/developer use and their API might change without notice.
_checkClosed
_checkReadable
_checkSeekable
_checkWritable
_copy_tempfiles
Copies created images from tempfiles to a subfolder of baseline images. _get_final_filenames
Helper function returning the :return: _upload_images
Uploads images to imgur unless explicitly deactivated with option no_uploads (to speed up tests that are expected to fail). Special Methods
__dir__
Default dir() implementation. __enter__
Set matplotlib defaults. __exit__
Remove tempfiles and store created images if OBSPY_KEEP_IMAGES environment variable is set. __format__
Default object formatter. __init__
Initialize self. __init_subclass__
This method is called when a class is subclassed. __new__
Create and return a new object. __reduce__
Helper for pickle. __reduce_ex__
Helper for pickle. __sizeof__
Size of object in memory, in bytes. __subclasshook__
Abstract classes can override this to customize issubclass().