Travis CI: Run each failing pytest in allow_failures mode

Author: cclauss

.travis.yml

@@ -10,24 +10,32 @@ matrix:
     # The following files currently fail pytests.  See issues: #1016, #1044, #1080
     # Here they are run allow_failures mode and when each passes pytest, it can be
     # removed BOTH lists below.  Complex now but simple once all files pass pytest.
-    - before_script: FILE=data_structures/stacks/balanced_parentheses.py
+    - env: FILE=data_structures/stacks/balanced_parentheses.py
+      before_script: true  # override main
       script: pytest ${FILE} --doctest-modules
-    - before_script: FILE=data_structures/stacks/infix_to_postfix_conversion.py
+    - env: FILE=data_structures/stacks/infix_to_postfix_conversion.py
+      before_script: true
       script: pytest ${FILE} --doctest-modules
-    # - before_script: FILE=file_transfer_protocol/ftp_client_server.py
+    # - env: FILE=file_transfer_protocol/ftp_client_server.py
+    #   before_script: true
     #   script: pytest ${FILE} --doctest-modules
-    - before_script: FILE=file_transfer_protocol/ftp_send_receive.py
+    - env: FILE=file_transfer_protocol/ftp_send_receive.py
+      before_script: true
       script: pytest ${FILE} --doctest-modules
-    - before_script: FILE=machine_learning/linear_regression.py
+    - env: FILE=machine_learning/linear_regression.py
+      before_script: true
       script: pytest ${FILE} --doctest-modules
-    - before_script: FILE=machine_learning/perceptron.py
+    - env: FILE=machine_learning/perceptron.py
+      before_script: true
       script: pytest ${FILE} --doctest-modules
-    - before_script: FILE=machine_learning/random_forest_classification/random_forest_classification.py
+    - env: FILE=machine_learning/random_forest_classification/random_forest_classification.py
+      before_script: true
       script: pytest ${FILE} --doctest-modules
-    - before_script: FILE=machine_learning/random_forest_regression/random_forest_regression.py
+    - env: FILE=machine_learning/random_forest_regression/random_forest_regression.py
+      before_script: true
       script: pytest ${FILE} --doctest-modules
   allow_failures:
-    - script: pytest ${FILE} --doctest-modules
+    - before_script: true
 before_script:
   - black --check . || true
   - flake8 . --count --select=E9,F401,F63,F7,F82 --show-source --statistics