feat: add cli option

Author: dzhang32

cookiecutter.json

@@ -4,5 +4,6 @@
     "version": "0.1.0",
     "description": "What's the main goal of this package?",
     "python_version": "3.13",
-    "year": "2025"
+    "year": "2025",
+    "include_cli": "n"
 }

{{cookiecutter.package_name}}/pyproject.toml

@@ -8,7 +8,11 @@ authors = [
 readme = "README.md"
 license = { file = "LICENSE" }
 requires-python = ">={{cookiecutter.python_version}}"
-dependencies = []
+dependencies = [
+    {% if cookiecutter.include_cli == 'y' %}
+    "click==8.1.7",
+    {% endif %}
+]
 
 [project.optional-dependencies]
 dev = [
@@ -17,9 +21,11 @@ dev = [
     "pytest-cov==6.0.0",
 ]
 
-[build-system]
-requires = ["uv_build>=0.8.14,<0.9.0"]
-build-backend = "uv_build"
+{% if cookiecutter.include_cli == 'y' %}
+[project.scripts]
+{{cookiecutter.package_name}} = "{{cookiecutter.package_name}}.__main__:cli"
+{% endif %}
 
-[tool.pytest.ini_options]
-pythonpath = ["src"]
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"

{{cookiecutter.package_name}}/src/{{cookiecutter.package_name}}/add_one.py

@@ -1,5 +1,34 @@
 from pathlib import Path
 
+{% if cookiecutter.include_cli == 'y' %}
+import click
+
+
+@click.command(
+    help="""
+    Add one to each line in the input file.
+    """
+)
+@click.option(
+    "--input-path",
+    type=click.Path(exists=True, path_type=Path),
+    required=True,
+    help="Path to the input files containing one integer per line.",
+)
+@click.option(
+    "--output-path",
+    type=click.Path(path_type=Path),
+    required=True,
+    help="Path to the output file containing the integers plus one.",
+)
+def add_one_cli(input_path: Path, output_path: Path) -> None:
+    """
+    Add one to each line in the input file.
+    """
+    with open(output_path, "w") as output_file:
+        for n_plus_1 in add_one_file(input_path):
+            output_file.write(str(n_plus_1) + "\n")
+{% endif %}
 
 def add_one_file(input_file: Path) -> list[int]:
     """

{{cookiecutter.package_name}}/src/{{cookiecutter.package_name}}/{% if cookiecutter.include_cli == 'y' %}__main__.py{% endif %}

@@ -0,0 +1,11 @@
+import click
+
+from {{cookiecutter.package_name}}.add_one import add_one_cli
+
+@click.group()
+def cli() -> None:
+    pass
+
+
+# Add subcommands.
+cli.add_command(add_one_cli)

{{cookiecutter.package_name}}/tests/__init__.py

@@ -1,6 +1,40 @@
 from {{cookiecutter.package_name}}.add_one import add_one, add_one_file
+{% if cookiecutter.include_cli == 'y' %}
+from {{cookiecutter.package_name}}.add_one import add_one_cli
+from {{cookiecutter.package_name}}.__main__ import cli
+
+from click.testing import CliRunner
+import tempfile
+{% endif %}
+
 from pathlib import Path
 
+{% if cookiecutter.include_cli == 'y' %}
+def test_add_one_cli(test_data_dir: Path) -> None:
+    """
+    Test the add_one_cli function works correctly.
+    """
+    input_path = test_data_dir / "test_add_one" / "integers.txt"
+
+    with tempfile.TemporaryDirectory() as tmp_dir:
+        output_path = Path(tmp_dir) / "output.txt"
+
+        runner = CliRunner()
+        result = runner.invoke(
+            cli,
+            [
+                "add-one-cli",
+                "--input-path",
+                str(input_path),
+                "--output-path",
+                str(output_path),
+            ],
+        )
+
+        assert result.exit_code == 0
+        assert output_path.read_text() == "2\n3\n4\n"
+{% endif %}
+
 def test_add_one_file(test_data_dir: Path) -> None:
     """
     Test that the add_one_file function works correctly.