Improve validate solutions script & fix pre-commit error (#3253)

* Trying to time every solution

* Proposal 2 for timing PE solutions:

- Use pytest fixture along with --capture=no flag to print out the
  top DURATIONS slowest solution at the end of the test sessions.
- Remove the print part and try ... except ... block from the test
  function.

* Proposal 3 for timing PE solutions:

Completely changed the way I was performing the tests. Instead of
parametrizing the problem numbers and expected output, I will
parametrize the solution file path.

Steps:
- Collect all the solution file paths
- Convert the paths into a Python module
- Call solution on the module
- Assert the answer with the expected results

For assertion, it was needed to convert the JSON list object to
Python dictionary object which required changing the JSON file itself.

* Add type hints for variables

* Fix whitespace in single_qubit_measure

.travis.yml

@@ -16,10 +16,8 @@ jobs:
       script:
         - pytest --doctest-modules --durations=10 --cov-report=term-missing:skip-covered --cov=project_euler/ project_euler/
     - name: Project Euler Solution
-      install:
-        - pip install pytest-subtests
       script:
-        - pytest --tb=short project_euler/validate_solutions.py
+        - pytest --tb=short --durations=10 project_euler/validate_solutions.py
 after_success:
   - scripts/build_directory_md.py 2>&1 | tee DIRECTORY.md
 notifications:

project_euler/validate_solutions.py

@@ -3,7 +3,7 @@ import importlib.util
 import json
 import pathlib
 from types import ModuleType
-from typing import Generator
+from typing import Dict, List
 
 import pytest
 
@@ -13,42 +13,44 @@ PROJECT_EULER_ANSWERS_PATH = PROJECT_EULER_DIR_PATH.joinpath(
 )
 
 with open(PROJECT_EULER_ANSWERS_PATH) as file_handle:
-    PROBLEM_ANSWERS = json.load(file_handle)
+    PROBLEM_ANSWERS: Dict[str, str] = json.load(file_handle)
 
 
-def generate_solution_modules(
+def convert_path_to_module(file_path: pathlib.Path) -> ModuleType:
-    dir_path: pathlib.Path,
+    """Converts a file path to a Python module"""
-) -> Generator[ModuleType, None, None]:
+    spec = importlib.util.spec_from_file_location(file_path.name, str(file_path))
-    # Iterating over every file or directory
+    module = importlib.util.module_from_spec(spec)
-    for file_path in dir_path.iterdir():
+    spec.loader.exec_module(module)
-        if file_path.suffix != ".py" or file_path.name.startswith(("_", "test")):
+    return module
+
+
+def collect_solution_file_paths() -> List[pathlib.Path]:
+    """Collects all the solution file path in the Project Euler directory"""
+    solution_file_paths = []
+    for problem_dir_path in PROJECT_EULER_DIR_PATH.iterdir():
+        if problem_dir_path.is_file() or problem_dir_path.name.startswith("_"):
             continue
-        # Importing the source file through the given path
+        for file_path in problem_dir_path.iterdir():
-        # https://docs.python.org/3/library/importlib.html#importing-a-source-file-directly
+            if file_path.suffix != ".py" or file_path.name.startswith(("_", "test")):
-        spec = importlib.util.spec_from_file_location(file_path.name, str(file_path))
+                continue
-        module = importlib.util.module_from_spec(spec)
+            solution_file_paths.append(file_path)
-        spec.loader.exec_module(module)
+    return solution_file_paths
-        yield module
 
 
-@pytest.mark.parametrize("problem_number, expected", PROBLEM_ANSWERS)
+def expand_parameters(param: pathlib.Path) -> str:
-def test_project_euler(subtests, problem_number: int, expected: str):
+    """Expand parameters in pytest parametrize"""
-    problem_dir = PROJECT_EULER_DIR_PATH.joinpath(f"problem_{problem_number:02}")
+    project_dirname = param.parent.name
-    # Check if the problem directory exist. If not, then skip.
+    solution_filename = param.name
-    if problem_dir.is_dir():
+    return f"{project_dirname}/{solution_filename}"
-        for solution_module in generate_solution_modules(problem_dir):
+
-            # All the tests in a loop is considered as one test by pytest so, use
+
-            # subtests to make sure all the subtests are considered as different.
+@pytest.mark.parametrize(
-            with subtests.test(
+    "solution_path", collect_solution_file_paths(), ids=expand_parameters
-                msg=f"Problem {problem_number} tests", solution_module=solution_module
+)
-            ):
+def test_project_euler(solution_path: pathlib.Path):
-                try:
+    """Testing for all Project Euler solutions"""
-                    answer = str(solution_module.solution())
+    problem_number: str = solution_path.parent.name[8:]  # problem_[extract his part]
-                    assert answer == expected, f"Expected {expected} but got {answer}"
+    expected: str = PROBLEM_ANSWERS[problem_number]
-                except (AssertionError, AttributeError, TypeError) as err:
+    solution_module = convert_path_to_module(solution_path)
-                    print(
+    answer = str(solution_module.solution())
-                        f"problem_{problem_number:02}/{solution_module.__name__}: {err}"
+    assert answer == expected, f"Expected {expected} but got {answer}"
-                    )
-                    raise
-    else:
-        pytest.skip(f"Solution {problem_number} does not exist yet.")

quantum/single_qubit_measure.py

@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 """
-Build a simple bare-minimum quantum circuit that starts with a single 
+Build a simple bare-minimum quantum circuit that starts with a single
-qubit (by default, in state 0), runs the experiment 1000 times, and 
+qubit (by default, in state 0), runs the experiment 1000 times, and
 finally prints the total count of the states finally observed.
 Qiskit Docs: https://qiskit.org/documentation/getting_started.html
 """