🎨 Palette: CLI UX polish and test upgrade

project/app.py

@@ -1,16 +1,23 @@
-from click import command, option
+import click
 
 
-@command(context_settings={"help_option_names": ["-h", "--help"]}, help="Say hello")
-@option("-n", "--name", default="World", help="Name", show_default=True)
+@click.command(context_settings={"help_option_names": ["-h", "--help"]}, help="Say hello to a user.")
+@click.option(
+    "-n",
+    "--name",
+    default="World",
+    help="The name of the person to greet.",
+    show_default=True,
+)
+@click.version_option()
 def main(name: str = "World"):
     """
     Say hello to the given name.
 
     Args:
       name: the name to be greeted
     """
-    print(f"Hello {name}!")
+    click.secho(f"Hello {name}! 👋", fg="green", bold=True)
 
 
 if __name__ == "__main__":

tests/test_app.py

@@ -1,9 +1,30 @@
-from pytest import main
+from click.testing import CliRunner
+
+from project.app import main
 
 
 def test_main():
-    pass
+    runner = CliRunner()
+    result = runner.invoke(main, ["--name", "Jules"])
+    assert result.exit_code == 0
+    assert "Hello Jules! 👋" in result.output
+
+
+def test_main_default():
+    runner = CliRunner()
+    result = runner.invoke(main)
+    assert result.exit_code == 0
+    assert "Hello World! 👋" in result.output
+
+
+def test_version():
+    runner = CliRunner()
+    result = runner.invoke(main, ["--version"])
+    assert result.exit_code == 0
+    assert "version" in result.output.lower()
 
 
 if __name__ == "__main__":
-    main()
+    import pytest
+
+    pytest.main()