add test checking if tests exist in source code

romanisim/tests/test_requirements.py

@@ -0,0 +1,40 @@
+import json
+import re
+from pathlib import Path
+
+TEST_REQUIREMENTS_FILENAME = (
+    Path(__file__).parent.parent.parent / "test_requirements.json"
+)
+TEST_DIRECTORY = Path(__file__).parent.parent
+
+
+def test_requirements():
+    test_requirements_filename = TEST_REQUIREMENTS_FILENAME.expanduser().absolute()
+    test_directory = TEST_DIRECTORY.expanduser().absolute()
+
+    with open(test_requirements_filename) as test_requirements_file:
+        requirements = json.load(test_requirements_file)
+
+    required_tests = sorted(
+        {
+            test
+            for requirement_tests in requirements.values()
+            for test in requirement_tests
+        }
+    )
+
+    existing_tests = []
+    test_regex = re.compile(r"def (test_[^\(]+)\(.*\):")
+    for test_filename in test_directory.glob("**/test_*.py"):
+        with open(test_filename) as test_file:
+            test_file_contents = test_file.read()
+
+        for match in re.finditer(test_regex, test_file_contents):
+            test = f"{test_directory.stem}.{str(test_filename.relative_to(test_directory).parent).replace('/', '.')}.{test_filename.stem}.{match.group(1)}"
+            if test in required_tests:
+                existing_tests.append(test)
+
+    existing_tests = sorted(existing_tests)
+
+    assert existing_tests == required_tests
+