Revisit coverage reporting: use coveragepy directly

.coveragerc

@@ -1,6 +1,8 @@
 [run]
-parallel = true
-source = .
-branch = true
+parallel = 1
+source = ${PYTESTDJANGO_COVERAGE_SRC}.
+branch = 1
+
 [report]
 include = pytest_django/*,pytest_django_test/*,tests/*
+skip_covered = 1

.travis.yml

@@ -5,45 +5,46 @@ dist: trusty
 jobs:
   fast_finish: true
   include:
-    # py37 is not available in trusty dist, and requires sudo=true with xenial.
+    - stage: baseline
+      python: 3.6
+      env: TOXENV=py36-dj20-postgres-coverage
+    - python: 3.6
+      env: TOXENV=py36-dj111-sqlite-coverage
+    - python: 2.7
+      env: TOXENV=py27-dj111-mysql_innodb-coverage
+    - python: 3.6
+      env: TOXENV=checkqa,docs
+
     - stage: test
+      # py37 is not available in trusty dist, and requires sudo=true with xenial.
       python: 3.7
-      env: TOXENV=py37-dj21-sqlite
+      env: TOXENV=py37-dj21-sqlite-coverage
       dist: xenial
       sudo: true
 
     - python: 3.6
-      env: TOXENV=py36-djmaster-sqlite
-    - python: 3.6
-      env: TOXENV=py36-dj20-postgres
-    - python: 3.6
-      env: TOXENV=py36-dj111-sqlite
+      env: TOXENV=py36-djmaster-sqlite-coverage
 
     - python: 3.5
-      env: TOXENV=py35-dj110-postgres
+      env: TOXENV=py35-dj110-postgres-coverage
 
     - python: 3.4
-      env: TOXENV=py34-dj19-sqlite_file
+      env: TOXENV=py34-dj19-sqlite_file-coverage
 
     - python: 2.7
-      env: TOXENV=py27-dj111-mysql_innodb
-    - python: 2.7
-      env: TOXENV=py27-dj111-mysql_myisam
+      env: TOXENV=py27-dj111-mysql_myisam-coverage
     - python: 2.7
-      env: TOXENV=py27-dj18-postgres
+      env: TOXENV=py27-dj18-postgres-coverage
 
     # pypy/pypy3: not included with coverage reports (much slower then).
     - python: pypy
-      env: TOXENV=pypy-dj111-sqlite_file SKIP_COVERAGE=1
+      env: TOXENV=pypy-dj111-sqlite_file
     - python: pypy3
-      env: TOXENV=pypy3-dj110-sqlite SKIP_COVERAGE=1
-
-    - python: 3.6
-      env: TOXENV=checkqa,docs SKIP_COVERAGE=1
+      env: TOXENV=pypy3-dj110-sqlite
 
     - stage: test_release
       python: 3.6
-      env: TOXENV=py36-dj20-postgres SKIP_COVERAGE=1
+      env: TOXENV=py36-dj20-postgres
 
     - stage: release
       script: skip
@@ -61,9 +62,11 @@ jobs:
   # NOTE: does not show up in "allowed failures" section, but is allowed to
   # fail (for the "test" stage).
   allow_failures:
-    - env: TOXENV=py36-djmaster-sqlite
+    - env: TOXENV=py36-djmaster-sqlite-coverage
 
 stages:
+  - name: baseline
+    if: tag IS NOT present
   - name: test
     if: tag IS NOT present
   - name: test_release
@@ -73,31 +76,16 @@ stages:
 
 install:
   - pip install tox==3.3.0
-  - |
-    # Setup coverage tracking.
-    if [[ "$SKIP_COVERAGE" != "1" ]]; then
-      PYTEST_DJANGO_COVERAGE=1
-      export PYTEST_ADDOPTS='--cov=pytest_django --cov=tests --cov=pytest_django_test --cov-report=term-missing:skip-covered'
-      export _PYTESTDJANGO_TOX_EXTRA_DEPS='pytest-cov==2.5.1'
-    else
-      PYTEST_DJANGO_COVERAGE=0
-    fi
 
 script:
   - tox
 
 after_success:
   - |
     set -ex
-    if [[ "$PYTEST_DJANGO_COVERAGE" = 1 ]]; then
-      pip install codecov
-
-      coverage --version
-      coverage combine
-      coverage xml
-
-      codecov_flags=${TOXENV//./}
-      codecov_flags=${codecov_flags//-/ }
-      codecov --required -X search gcov pycov -f coverage.xml --flags $codecov_flags
+    if [[ "${TOXENV%-coverage}" != "$TOXENV" ]]; then
+      codecov_flags=${TOXENV%-coverage}
+      codecov_flags=${codecov_flags//-/,}
+      bash <(curl -s https://codecov.io/bash) -Z -X gcov -X xcode -X gcovout -F "$codecov_flags"
     fi
     set +x

tox.ini

@@ -9,8 +9,6 @@ envlist =
 [testenv]
 extras = testing
 deps =
-    {env:_PYTESTDJANGO_TOX_EXTRA_DEPS:}
-
     djmaster: https://github.com/django/django/archive/master.tar.gz
     dj21: Django>=2.1a1,<2.2
     dj20: Django>=2.0a1,<2.1
@@ -23,24 +21,30 @@ deps =
     mysql_innodb: mysql-python==1.2.5
 
     postgres: psycopg2-binary
+    coverage: coverage-enable-subprocess
+
 setenv =
     PYTHONPATH = {toxinidir}:{env:PYTHONPATH:}
 
-    # Ref: https://github.com/pytest-dev/pytest-django/pull/412#issuecomment-340077539
-    COV_CORE_SOURCE={toxinidir}
-    COV_CORE_CONFIG={toxinidir}/.coveragerc
-    COV_CORE_DATAFILE={toxinidir}/.coverage.eager
-
     mysql_innodb: DJANGO_SETTINGS_MODULE=pytest_django_test.settings_mysql_innodb
     mysql_myisam: DJANGO_SETTINGS_MODULE=pytest_django_test.settings_mysql_myisam
     postgres:     DJANGO_SETTINGS_MODULE=pytest_django_test.settings_postgres
     sqlite:       DJANGO_SETTINGS_MODULE=pytest_django_test.settings_sqlite
     sqlite_file:  DJANGO_SETTINGS_MODULE=pytest_django_test.settings_sqlite_file
 
+    coverage: PYTESTDJANGO_TEST_RUNNER=coverage run -m pytest
+    coverage: COVERAGE_PROCESS_START={toxinidir}/.coveragerc
+    coverage: COVERAGE_FILE={toxinidir}/.coverage
+    coverage: PYTESTDJANGO_COVERAGE_SRC={toxinidir}/
+
 passenv = PYTEST_ADDOPTS
 usedevelop = True
 commands =
-    pytest --strict {posargs:tests}
+    coverage: coverage erase
+    {env:PYTESTDJANGO_TEST_RUNNER:pytest} {posargs:tests}
+    coverage: coverage combine
+    coverage: coverage report
+    coverage: coverage xml
 
 [testenv:checkqa]
 deps =