fix the build error on setup.py test

.github/workflows/cmake.yml

@@ -63,7 +63,7 @@ jobs:
       working-directory: ${{github.workspace}}/python
       run: |
         python -m pip install --require-hashes --no-dependencies -r ../.github/workflows/requirements/base.txt
-        python setup.py test
+        python -m pytest
         python setup.py bdist_wheel
 
     - name: Upload artifcacts

.github/workflows/requirements/base.in

@@ -2,3 +2,4 @@ pip
 setuptools
 wheel
 twine
+pytest

python/setup.py

@@ -211,4 +211,5 @@ def get_win_arch():
         'Topic :: Software Development :: Libraries :: Python Modules',
     ],
     test_suite='sentencepiece_test.suite',
+    tests_require=['pytest'],
 )

python/test/sentencepiece_test.py

@@ -15,11 +15,14 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.!
 
+import sys
+
+sys.path.insert(0, 'src')
+
 from collections import defaultdict
 import io
 import os
 import pickle
-import sys
 import unittest
 import sentencepiece as spm