tox.ini: Support running tests without coverage present at all

This change simply makes it possible to run the tests without
coverage and without any coverage related dependencies present
in the tox venvs.

To run tests without coverage, simply choose the python version
and append "-nocover" to the env name, e.g.:

    tox -e py36-nocover

1 files changed, 13 insertions, 7 deletions

diff --git a/tox.ini b/tox.ini
index c48db7a4c..3c401ba4f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -12,14 +12,20 @@ skip_missing_interpreters = true
 #
 [testenv]
 commands =
-    pytest --basetemp {envtmpdir} --cov=buildstream --cov-config .coveragerc {posargs}
-    mkdir -p .coverage-reports
-    mv {envtmpdir}/.coverage {toxinidir}/.coverage-reports/.coverage.{env:COVERAGE_PREFIX:}{envname}
+    # Running with coverage reporting enabled
+    py{35,36,37}-!nocover: pytest --basetemp {envtmpdir} --cov=buildstream --cov-config .coveragerc {posargs}
+    py{35,36,37}-!nocover: mkdir -p .coverage-reports
+    py{35,36,37}-!nocover: mv {envtmpdir}/.coverage {toxinidir}/.coverage-reports/.coverage.{env:COVERAGE_PREFIX:}{envname}
+
+    # Running with coverage reporting disabled
+    py{35,36,37}-nocover: pytest --basetemp {envtmpdir} {posargs}
 deps =
-    -rrequirements/requirements.txt
-    -rrequirements/dev-requirements.txt
-    -rrequirements/cov-requirements.txt
-    -rrequirements/plugin-requirements.txt
+    py{35,36,37}: -rrequirements/requirements.txt
+    py{35,36,37}: -rrequirements/dev-requirements.txt
+    py{35,36,37}: -rrequirements/plugin-requirements.txt
+
+    # Only require coverage and pytest-cov when using it
+    !nocover: -rrequirements/cov-requirements.txt
 passenv =
     BST_FORCE_BACKEND
     GI_TYPELIB_PATH