Go straight to a file with the subunit2 output.

It's just too hard otherwise.

.circleci/run-tests.sh

@@ -12,7 +12,6 @@ shift || :
 # Make sure we can actually write things to this directory.
 sudo --user nobody mkdir -p "${ARTIFACTS}"
 
-TOX_JSON="${ARTIFACTS}"/tox-result.json
 SUBUNIT2="${ARTIFACTS}"/results.subunit2
 
 # Use an intermediate directory here because CircleCI extracts some label
@@ -26,33 +25,20 @@ JUNITXML="${ARTIFACTS}"/junit/unittests/results.xml
 # Also run with /tmp as a workdir because the non-root user won't be able to
 # create the tox working filesystem state in the source checkout because it is
 # owned by root.
-sudo TAHOE_LAFS_TRIAL_ARGS="--reporter=subunitv2" \
+#
+# Send the output directly to a file because transporting the binary subunit2
+# via tox and then scraping it out is hideous and failure prone.
+sudo \
+    SUBUNITREPORTER_OUTPUT_PATH="${SUBUNIT2}" \
+    TAHOE_LAFS_TRIAL_ARGS="--reporter=subunitv2-file" \
      --set-home \
      --user nobody \
      /tmp/tests/bin/tox \
      -c /tmp/project/tox.ini \
-     --result-json "${TOX_JSON}" \
      --workdir /tmp/tahoe-lafs.tox \
      -e "${TAHOE_LAFS_TOX_ENVIRONMENT}" \
      ${TAHOE_LAFS_TOX_ARGS}
 
-# Extract the test process output which should be subunit2-format.
-/tmp/tests/bin/python -c '
-from json import load
-from sys import stdin, stdout, argv
-result = load(stdin)
-for environ in argv[1].split(","):
-    # Heuristically discover which blob is probably the test output!
-    test_result = next(
-        result
-        for result
-        in result["testenvs"][environ]["test"]
-        if "test: allmydata." in result["output"]
-    )
-    messy_output = test_result["output"]
-    stdout.write(messy_output.split("\n", 3)[3].strip() + "\n")
-' "${TAHOE_LAFS_TOX_ENVIRONMENT}" < "${TOX_JSON}" > "${SUBUNIT2}"
-
 # Create a junitxml results area.
 mkdir -p "$(dirname "${JUNITXML}")"
 /tmp/tests/bin/subunit2junitxml < "${SUBUNIT2}" > "${JUNITXML}"

.circleci/setup-virtualenv.sh

@@ -10,6 +10,14 @@ shift || :
 # non-root user.  See below.
 sudo --set-home -u nobody virtualenv --python python2.7 /tmp/tests
 
+# Get "certifi" to avoid bug #2913. Basically if a `setup_requires=...` causes
+# a package to be installed (with setuptools) then it'll fail on certain
+# platforms (travis's OX-X 10.12, Slackware 14.2) because PyPI's TLS
+# requirements (TLS >= 1.2) are incompatible with the old TLS clients
+# available to those systems.  Installing it ahead of time (with pip) avoids
+# this problem.
+sudo --set-home -u nobody PIP_FIND_LINKS=/tmp/packages /tmp/tests/bin/pip install certifi
+
 # Python packages we need to support the test infrastructure.  *Not* packages
 # Tahoe-LAFS itself (implementation or test suite) need.
 TEST_DEPS="tox codecov"

tox.ini

@@ -13,7 +13,7 @@ skipsdist = True
 
 [testenv]
 basepython=python2.7
-passenv = TAHOE_LAFS_* USERPROFILE HOMEDRIVE HOMEPATH
+passenv = TAHOE_LAFS_* SUBUNITREPORTER_* USERPROFILE HOMEDRIVE HOMEPATH
 # Get "certifi" to avoid bug #2913. Basically if a `setup_requires=...` causes
 # a package to be installed (with setuptools) then it'll fail on certain
 # platforms (travis's OX-X 10.12, Slackware 14.2) because PyPI's TLS