Use {toxinidir} instead of cwd-platform specifics in coverage env vars

Author: nicoddemus

.travis.yml

@@ -82,7 +82,7 @@ env:
 before_script:
   - |
     if [[ "$PYTEST_NO_COVERAGE" != 1 ]]; then
-      export _PYTEST_TOX_COVERAGE_RUN="env COVERAGE_FILE=$PWD/.coverage COVERAGE_PROCESS_START=$PWD/.coveragerc coverage run --source {envsitepackagesdir}/_pytest/,$PWD/testing -m"
+      export _PYTEST_TOX_COVERAGE_RUN="env COVERAGE_FILE={toxinidir}/.coverage COVERAGE_PROCESS_START={toxinidir}/.coveragerc coverage run --source {envsitepackagesdir}/_pytest/,{toxinidir}/testing -m"
       export _PYTEST_TOX_EXTRA_DEP=coverage-enable-subprocess
     fi
 

scripts/prepare-coverage.bat

@@ -1,5 +1,5 @@
 if not defined PYTEST_NO_COVERAGE (
-    set "_PYTEST_TOX_COVERAGE_RUN=coverage run --source {envsitepackagesdir}/_pytest/,%CD%/testing -m"
+    set "_PYTEST_TOX_COVERAGE_RUN=coverage run --source {envsitepackagesdir}/_pytest/,{toxinidir}/testing -m"
     set "_PYTEST_TOX_EXTRA_DEP=coverage-enable-subprocess"
     set COVERAGE_DEBUG=config,multiproc,process,self,sys,trace
     echo Coverage setup completed