fix reading incorrect input in #1710 test case

A mistake in 632fe0bd1cfc6a4f636db4f85206aff6720bdc6b made this test read from
/dev/null instead of the input file it was supposed to read. Note that this
required some tweak to the skip condition. The Windows platforms on which this
fails seems all over the place and expressing the exact pattern seemed too
complex. For the curious, what we currently see in CI is:

  ┌──────────────┬─────────┬──────────────┬─────────┬────────┐
  │ architecture │ OS      │ build system │ mode    │ result │
  ╞══════════════╪═════════╪══════════════╪═════════╪════════╡
  │ x86          │ Windows │ MS Build     │ debug   │ FAIL   │
  │              │         │              ├─────────┼────────┤
  │              │         │              │ release │ pass   │
  │              │         ├──────────────┼─────────┼────────┤
  │              │         │ CMake        │ debug   │ FAIL   │
  │              │         │              ├─────────┼────────┤
  │              │         │              │ release │ FAIL   │
  │              ├─────────┼──────────────┼─────────┼────────┤
  │              │ MinGW   │ CMake        │ -       │ pass   │
  ├──────────────┼─────────┼──────────────┼─────────┼────────┤
  │ x86-64       │ Windows │ CMake        │ debug   │ FAIL   │
  │              │         │              ├─────────┼────────┤
  │              │         │              │ release │ FAIL   │
  │              ├─────────┼──────────────┼─────────┼────────┤
  │              │ MinGW   │ CMake        │ -       │ FAIL   │
  └──────────────┴─────────┴──────────────┴─────────┴────────┘

I would not be surprised if these results are not stable. It is likely this
failure presents across all platforms, but is dependent on things like Address
Space Layout Randomization to exhibit.

Gitlab: #1710, #1720

diff --git a/tests/regression_tests/large/test_large_graphs.py b/tests/regression_tests/large/test_large_graphs.py
index bb32196c6f9801563ddd11af7e7a2db1e4a34c1f..3577ee1a9c92803d10530861ce1b714959a7cbee 100644 (file)
--- a/tests/regression_tests/large/test_large_graphs.py
+++ b/tests/regression_tests/large/test_large_graphs.py
@@ -12,9 +12,8 @@ import pytest
 sys.path.append(os.path.join(os.path.dirname(__file__), "../../../tests"))
 from gvtest import dot #pylint: disable=wrong-import-position
 
-@pytest.mark.skipif(platform.system() == "Windows" and
-                    platform.architecture()[0] == "32bit",
-                    reason="https://gitlab.com/graphviz/graphviz/-/issues/1710")
+@pytest.mark.xfail(platform.system() == "Windows",
+                   reason="https://gitlab.com/graphviz/graphviz/-/issues/1710")
 def test_long_chain():
   """
   This test will fail on 32bit Windows machine if compiled with stack size < 16MB.
@@ -37,7 +36,7 @@ def test_long_chain():
     graph.render("long_chain")
   """
   subprocess.check_call([
-    "dot", "-Tsvg", "-O", os.devnull
+    "dot", "-Tsvg", "-o", os.devnull, Path(__file__).parent / "long_chain"
   ])
 
 def test_wide_clusters():