Make single command as subcommands with documentation.

src/serious_scaffold/cli.py

@@ -9,6 +9,19 @@ def run() -> None:
     """Run command."""
 
 
+# NOTE(huxuan): callback is required for single command as a subcommand in typer.
+# And it is a convenient way to document the cli here.
+# Reference: https://typer.tiangolo.com/tutorial/commands/one-or-multiple/#one-command-and-one-callback
+# BTW, `no_args_is_help` is set to `True` to avoid error when invoking the cli with no
+# subcommands. The default behavior is strange and might change in the future.
+# Reference: https://github.com/tiangolo/typer/issues/328
+@app.callback(no_args_is_help=True)
+def main() -> None:
+    """CLI for Serious Scaffold Python."""
+
+
+# NOTE(huxuan): click object is used for document generation.
+# Reference: https://github.com/tiangolo/typer/issues/200#issuecomment-796485787
 typer_click_object = typer.main.get_command(app)
 
 

src/{{ module_name }}/cli.py.jinja

@@ -0,0 +1,29 @@
+"""Command Line Interface."""
+import typer
+
+app = typer.Typer()
+
+
+@app.command()
+def run() -> None:
+    """Run command."""
+
+
+# NOTE(huxuan): callback is required for single command as a subcommand in typer.
+# And it is a convenient way to document the cli here.
+# Reference: https://typer.tiangolo.com/tutorial/commands/one-or-multiple/#one-command-and-one-callback
+# BTW, `no_args_is_help` is set to `True` to avoid error when invoking the cli with no
+# subcommands. The default behavior is strange and might change in the future.
+# Reference: https://github.com/tiangolo/typer/issues/328
+@app.callback(no_args_is_help=True)
+def main() -> None:
+    """CLI for {{ project_name }}."""
+
+
+# NOTE(huxuan): click object is used for document generation.
+# Reference: https://github.com/tiangolo/typer/issues/200#issuecomment-796485787
+typer_click_object = typer.main.get_command(app)
+
+
+if __name__ == "__main__":
+    app()  # pragma: no cover

tests/cli_test.py

@@ -6,8 +6,15 @@
 runner = CliRunner()
 
 
-def test_app() -> None:
+def test_cli() -> None:
     """Tests for cli."""
     result = runner.invoke(app)
     assert result.exit_code == 0
+    assert "Usage" in result.output
+
+
+def test_cli_run() -> None:
+    """Tests for run subcommand of the cli."""
+    result = runner.invoke(app, "run")
+    assert result.exit_code == 0
     assert not result.output

tests/cli_test.py.jinja

@@ -6,8 +6,15 @@ from {{ module_name }}.cli import app
 runner = CliRunner()
 
 
-def test_app() -> None:
+def test_cli() -> None:
     """Tests for cli."""
     result = runner.invoke(app)
     assert result.exit_code == 0
+    assert "Usage" in result.output
+
+
+def test_cli_run() -> None:
+    """Tests for run subcommand of the cli."""
+    result = runner.invoke(app, "run")
+    assert result.exit_code == 0
     assert not result.output