`pkg grep`: use `capfd` instead of executable for tests

1 files changed, 5 insertions, 5 deletions

diff --git a/lib/spack/spack/test/cmd/pkg.py b/lib/spack/spack/test/cmd/pkg.py
index 2f1a1a6f3a..3f0b89309b 100644
--- a/lib/spack/spack/test/cmd/pkg.py
+++ b/lib/spack/spack/test/cmd/pkg.py
@@ -297,19 +297,19 @@ def test_pkg_hash(mock_packages):
 
 
 @pytest.mark.skipif(not spack.cmd.pkg.get_grep(), reason="grep is not installed")
-def test_pkg_grep(mock_packages, capsys):
+def test_pkg_grep(mock_packages, capfd):
     # only splice-* mock packages have the string "splice" in them
-    with capsys.disabled():
-        output = pkg("grep", "-l", "splice", output=str)
-
+    pkg("grep", "-l", "splice", output=str)
+    output, _ = capfd.readouterr()
     assert output.strip() == "\n".join(
         spack.repo.path.get_pkg_class(name).module.__file__
         for name in ["splice-a", "splice-h", "splice-t", "splice-vh", "splice-z"]
     )
 
     # ensure that this string isn't fouhnd
-    output = pkg("grep", "abcdefghijklmnopqrstuvwxyz", output=str, fail_on_error=False)
+    pkg("grep", "abcdefghijklmnopqrstuvwxyz", output=str, fail_on_error=False)
     assert pkg.returncode == 1
+    output, _ = capfd.readouterr()
     assert output.strip() == ""
 
     # ensure that we return > 1 for an error