[QGIS-Developer] compare failing/succeeding CI builds (how to?)

[Sandro Santilli]

My long-standing PR about preventing testsuite run from changing
files in source tree is currently having a Travis failure which
seems to start with:

    ProcessingQgisAlgorithmsTestPt3

Trying to understand what's going wrong with that test I see a lot
of warnings/errors being printed, like:

  GEOS exception: IllegalArgumentException: Points of LinearRing do not form a closed linestring
  ...
  ERROR 6: EPSG PCS/GCS code 7992 not found in EPSG support files.  Is this a valid EPSG coordinate system?

And eventually the actual failure printed in yellow:

	FAIL: test_algorithms:20
	'Find projection', {'algorithm': 'qgis:findprojection', 'name': 'Find projectio (__main__.TestQgisAlgorithms3)
	----------------------------------------------------------------------
	Traceback (most recent call last):
		File "/root/QGIS/python/plugins/processing/tests/AlgorithmsTestBase.py", line 154, in check_algorithm
			self.check_results(results, context, parameters, defs['results'])
		File "/root/QGIS/python/plugins/processing/tests/AlgorithmsTestBase.py", line 333, in check_results
			self.assertLayersEqual(expected_lyrs[0], result_lyr, compare=compare, pk=pk, geometry={'topo_equal_check': topo_equal_check})
		File "/root/QGIS/build/output/python/qgis/testing/__init__.py", line 57, in assertLayersEqual
			self.checkLayersEqual(layer_expected, layer_result, True, **kwargs)
		File "/root/QGIS/build/output/python/qgis/testing/__init__.py", line 96, in checkLayersEqual
			_TestCase.assertEqual(self, layer_expby_location_summary_date.gml'}

	Running alg: "qgis:joinbylocationsummary"
	Algorithm parameters are {'DISCARD_NONMATCHING': False, 'INPUT': 'polys_gml_layername_polys2_4874fd51_2ea0_4a57_9c29_180f0d10efcc', 'JOIN': 'custom_points_3857_gml_layername_points_3857_94fef703_91b6_4e6f_9a4a_4a26c1e3444f', 'PREDICATE': [0], 'SUMMARIES': [], 'OUTPUT': '/tmp/tmpbtipmdek/join_by_location_summary_reproject.gml'}

	Running alg: "qgis:joinbylocationsummary"
	Algorithm parameters are {'DISCARD_NONMATCHING': False, 'INPUT': 'custom_line_3857_gml_layername_line_3857_1f3feb18_ad23_4a7d_a11e_10f89e8499f7', 'JOIN': 'polys_gml_layername_polys2_aa54703b_6b44_4977_ad0d_9819432a6ca1', 'PREDICATE': [0], 'SUMMARIES': [], 'OUTPUT': '/tmp/tmpfc2zhzz8/join_by_location_line_to_polys_reproj.gml'}

	Running alg: "native:extractbyextent"
	Algorithm parameters are {'CLIP': False, 'EXTENT': '-1.1650000000000003,4.775,-2.444285714285715,3.4171428571428573', 'INPUT': 'polys_gml_17f9a2e4_2ead_4455_97ac_739eb78a8836', 'OUTPUT': '/tmp/tmp31zgit2o/extract_bected.featureCount(), layer_result.featureCount())

	AssertionError: 9 != 8
	----------------------------------------------------------------------

Now, as the test name mentions "projection" and one of the earlier errors are
about projections, I wanted to compare the failing run with the successful run
but the successful run is silent so I cannot compare. 

Would it make sense to enable verbosity on Travis for tests or should
I create a fake PR just for the sake of seeing those logs ?

Or more simply, can any other developers successfully running that
test let me know if those messages are printed ?

Thank you !

--strk;