Use xdist with multi-processing (#1410)

Author: yongtang

.github/workflows/build.wheel.sh

@@ -8,11 +8,8 @@ run_test() {
   CPYTHON_VERSION=$($entry -c 'import sys; print(str(sys.version_info[0])+str(sys.version_info[1]))')
   (cd wheelhouse && $entry -m pip install tensorflow_io_plugin_gs-*-cp${CPYTHON_VERSION}-*.whl)
   (cd wheelhouse && $entry -m pip install tensorflow_io-*-cp${CPYTHON_VERSION}-*.whl)
-  $entry -m pip install -q pytest pytest-benchmark boto3 fastavro avro-python3 scikit-image pandas pyarrow==3.0.0 google-cloud-pubsub==2.1.0 google-cloud-bigtable==1.6.0 google-cloud-bigquery-storage==1.1.0 google-cloud-bigquery==2.3.1 google-cloud-storage==1.32.0 PyYAML==5.3.1 azure-storage-blob==12.8.1
-  (cd tests && $entry -m pytest --benchmark-disable -v --import-mode=append $(find . -type f \( -iname "test_*_v1.py" \)))
-  (cd tests && $entry -m pytest --benchmark-disable -v --import-mode=append $(find . -type f \( -iname "test_*.py" ! \( -iname "test_*_v1.py" -o -iname "test_bigquery.py" \) \)))
-  # GRPC and test_bigquery tests have to be executed separately because of https://github.com/grpc/grpc/issues/20034
-  (cd tests && $entry -m pytest --benchmark-disable -v --import-mode=append $(find . -type f \( -iname "test_bigquery.py" \)))
+  $entry -m pip install -q pytest pytest-benchmark pytest-xdist boto3 fastavro avro-python3 scikit-image pandas pyarrow==3.0.0 google-cloud-pubsub==2.1.0 google-cloud-bigtable==1.6.0 google-cloud-bigquery-storage==1.1.0 google-cloud-bigquery==2.3.1 google-cloud-storage==1.32.0 PyYAML==5.3.1 azure-storage-blob==12.8.1
+  (cd tests && $entry -m pytest --benchmark-disable -v --import-mode=append --forked --numprocesses=auto --dist loadfile $(find . -type f \( -iname "test_*.py" \)))
 }
 
 PYTHON_VERSION=python
@@ -47,6 +44,7 @@ if [[ $(uname) == "Linux" ]]; then
   export CLASSPATH=$(${HADOOP_HOME}/bin/hadoop classpath --glob)
   export
 elif [[ $(uname) == "Darwin" ]]; then
-  brew install ffmpeg
+  echo "TODO: !!!pytest-xdist!!!"
+  echo brew install ffmpeg
 fi
 run_test $PYTHON_VERSION