Invoke test runner at a more granular level for pypy shard. (#513)

Fixes #497

.travis.yml

@@ -77,4 +77,4 @@ install:
   - pip install -U tox "setuptools<34"
 
 script:
-  - tox -v
+  - ./scripts/ci.sh

scripts/ci.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+set -euo pipefail
+
+if [[ "$TOXENV" == "pypy" ]]; then
+  echo "pypy shard detected. invoking workaround for https://github.com/travis-ci/travis-ci/issues/9706"
+  tox -e list-tests | grep ^"RUNNABLE" | grep -v "tests/test_integration.py" | awk -F'\t' '{print $NF}' | xargs -L1 tox -v
+else
+  tox -v
+fi

scripts/list_tests.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python
+
+import sys
+import pytest
+
+
+class Collector(object):
+
+  RUN_INDIVIDUALLY = ['tests/test_pex.py']
+
+  def __init__(self):
+    self._collected = set()
+
+  def iter_collected(self):
+    for collected in sorted(self._collected):
+      yield collected
+
+  def pytest_collectreport(self, report):
+    if report.failed:
+      raise pytest.UsageError('Errors during collection, aborting!')
+
+  def pytest_collection_modifyitems(self, items):
+    for item in items:
+      test_file = item.location[0]
+      if test_file in self.RUN_INDIVIDUALLY:
+        self._collected.add(item.nodeid)
+      else:
+        self._collected.add(test_file)
+
+
+collector = Collector()
+rv = pytest.main(['--collect-only'] + sys.argv[1:], plugins=[collector])
+
+for test_target in collector.iter_collected():
+  print('RUNNABLE\t"{}"'.format(test_target))
+
+sys.exit(rv)

tox.ini

@@ -19,8 +19,9 @@ deps =
     wheel==0.29.0
     packaging==16.8
     setuptools<34.0
-    py27: mock
-    pypy: mock
+    list-tests: mock==2.0.0
+    py27: mock==2.0.0
+    pypy: mock==2.0.0
     run: requests
     requests: requests
     requests: responses
@@ -55,6 +56,9 @@ commands =
     # This is necessary due to https://bitbucket.org/hpk42/tox/issue/175/cant-do-substitution-base-commands
     bash scripts/coverage.sh
 
+[testenv:list-tests]
+commands = python scripts/list_tests.py
+
 [testenv:py27-coverage]
 commands = {[integration]commands}