diff --git a/.travis.yml b/.travis.yml
index bea512264c19..7df50697b4a2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,17 @@ language: python
 dist: xenial  # required for Python >= 3.7
 python: 3.7
 cache: pip
+env:
+  - TEST_FILE=data_structures/stacks/balanced_parentheses.py
+  - TEST_FILE=data_structures/stacks/infix_to_postfix_conversion.py
+  - TEST_FILE=file_transfer_protocol/ftp_send_receive.py
+  - TEST_FILE=file_transfer_protocol/ftp_client_server.py
+  - TEST_FILE=machine_learning/linear_regression.py
+  - TEST_FILE=machine_learning/perceptron.py
+  - TEST_FILE=machine_learning/random_forest_classification/random_forest_classification.py
+  - TEST_FILE=machine_learning/random_forest_regression/random_forest_regression.py
+  - TEST_FILE=maths
+
 before_install: pip install --upgrade pip setuptools
 install: pip install -r requirements.txt
 before_script:
@@ -9,15 +20,8 @@ before_script:
   - flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
 script:
   - mypy --ignore-missing-imports .
-  - pytest . --doctest-modules
-      --ignore=data_structures/stacks/balanced_parentheses.py
-      --ignore=data_structures/stacks/infix_to_postfix_conversion.py
-      --ignore=file_transfer_protocol/ftp_send_receive.py
-      --ignore=file_transfer_protocol/ftp_client_server.py
-      --ignore=machine_learning/linear_regression.py
-      --ignore=machine_learning/perceptron.py
-      --ignore=machine_learning/random_forest_classification/random_forest_classification.py
-      --ignore=machine_learning/random_forest_regression/random_forest_regression.py
+  - echo "pytest --doctest-modules ${TEST_FILE}"
+  - pytest --doctest-modules ${TEST_FILE}
 after_success:
   - python scripts/build_directory_md.py
   - cat DIRECTORY.md