Fix ValueErrors raised when numpy iterables use == in failed

.github/workflows/ci.yaml

@@ -16,6 +16,7 @@ jobs:
       - name: Install dependencies
         run: |
           python setup.py develop
+          pip install numpy
 
       - name: Test
         shell: 'script -q -e -c "bash {0}"'

pytest_icdiff.py

@@ -23,6 +23,10 @@ def pytest_assertrepr_compare(config, op, left, right):
             return
     except TypeError:
         pass
+    except ValueError:
+        # ValueErrors are raised when numpy / pandas errors are checked
+        # Bail out of generating a diff and use pytest default output
+        return
 
     half_cols = COLS / 2 - MARGINS
 

tests/test_pytest_icdiff.py

@@ -2,6 +2,7 @@
 from unittest import mock
 import pytest
 import re
+import sys
 from pprintpp import pformat
 
 YELLOW_ON = '\x1b[1;33m'
@@ -292,3 +293,25 @@ def test_one():
     output = testdir.runpytest('-vv', '--color=yes', '-r=no').stdout.str()
     assert len(output.splitlines()) < 50
     assert "---" in output  # context split marker
+
+
+@pytest.mark.skipif('numpy' not in sys.modules, reason="requires numpy library")
+def test_np_arrays_can_use_equals(testdir) -> None:
+    """
+    Numpy iterables will fall back to pytest default output
+    """
+    testdir.makepyfile("""
+    import numpy as np
+
+    def test():
+        result = np.array([1, 2, 3])
+
+        assert all(result == 2)
+    """)
+
+    result = testdir.runpytest()
+
+    output = result.stdout.str()
+    assert 'ValueError' not in output
+    assert 'AssertionError' in output
+    assert 'where False = all(equals failed' not in output, 'pytest-icdiff not used'