diff options
Diffstat (limited to 'gnu/packages/patches/python-pydot-regression-test.patch')
| -rw-r--r-- | gnu/packages/patches/python-pydot-regression-test.patch | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/gnu/packages/patches/python-pydot-regression-test.patch b/gnu/packages/patches/python-pydot-regression-test.patch new file mode 100644 index 0000000000..d2f0f5996e --- /dev/null +++ b/gnu/packages/patches/python-pydot-regression-test.patch @@ -0,0 +1,79 @@ +This patch is taken from the upstream repository +https://github.com/pydot/pydot/commit/a10ced4d132361027a545a471af4541dea8c5cf5.patch +It should be included in the 1.4.2 release. + + +From a10ced4d132361027a545a471af4541dea8c5cf5 Mon Sep 17 00:00:00 2001 +From: Peter Nowee <peter@peternowee.com> +Date: Wed, 26 Jun 2019 15:43:38 +0800 +Subject: [PATCH] Fix multi.dot Graphviz regression test + +Commit d6602ad of 2018-12-01 fixed the regression test broken by commit +2d55978 of 2016-07-01. This revealed that `test/graphs/multi.dot` was +failing. + +`multi.dot` was introduced in commit 2b3f088 of 2010-11-07 together +with many of the other tests still here today. It has not been touched +since. It is a DOT-file containing two digraphs. The regression test +compares the JPEG images rendered from the DOT-file by pydot with those +rendered by Graphviz's dot directly. + +Commit 66734d2 of 2016-07-01 is the actual cause of the failure. It +changed one of the render methods of the regression test, +`_render_with_pydot`, from calculating a single hash for all the JPEG +images to calculating separate hashes for each JPEG image and then +concatenating those hashes in one long string. The other render method, +`_render_with_graphviz`, still calculates a single hash over all data. +For DOT-files that generate only one image the end result is the same, +but because `multi.dot` has two graphs, it produces two images and this +leads to comparing a string of two hashes with one single hash. + +I do not think the change in generating the hash was intentional, for +the following reasons: +- Commit 66734d2 states that its purpose was to adapt the test to an + API change in pydot. It does not mention a deliberate choice to + change the testing method. +- There was no effort to change `_render_with_graphviz` to also produce + multiple hashes. +- Except for easier debugging in case of a failing test with multiple + images (AFAICT, only `multi.dot`), I do not see much added benefit in + checking a concatenation of the hashes of all images vs. checking one + hash of all images together: In both cases the test will fail if one + or more images is rendered differently. +- Given that there were many commits authored that same hour, including + commit 2d55978 which broke the regression tests, I suspect the author + did not run the tests for each individual commit, but only at the end + of that batch, and was therefore also not alerted of this change by + the test suite. + +Assuming that the change was not intended, this commit will now revert +`_render_with_pydot` to the old behavior of calculating a single hash +from all JPEG image data. + +Tested with Debian 9.9, Graphviz 2.38.0-17, Python 2.7.13-2 and 3.5.3-1. + +Fixes https://github.com/pydot/pydot/issues/204. +--- + test/pydot_unittest.py | 8 ++++---- + 1 file changed, 4 insertions(+), 4 deletions(-) + +diff --git a/test/pydot_unittest.py b/test/pydot_unittest.py +index 881ee16..64aa856 100644 +--- a/test/pydot_unittest.py ++++ b/test/pydot_unittest.py +@@ -194,11 +194,11 @@ def _render_with_graphviz(self, filename, encoding): + + def _render_with_pydot(self, filename, encoding): + c = pydot.graph_from_dot_file(filename, encoding=encoding) +- sha = '' ++ jpe_data = bytearray() + for g in c: +- jpe_data = g.create(prog=TEST_PROGRAM, format='jpe', encoding=encoding) +- sha += sha256(jpe_data).hexdigest() +- return sha ++ jpe_data.extend(g.create(prog=TEST_PROGRAM, format='jpe', ++ encoding=encoding)) ++ return sha256(jpe_data).hexdigest() + + def test_my_regression_tests(self): + path = os.path.join(test_dir, TESTS_DIR_1) |