Fixed CLI help for invalid topic, closes #76

osxphotos/__main__.py

@@ -1149,9 +1149,12 @@ def help(ctx, topic, **kw):
     """ Print help; for help on commands: help <command>. """
     if topic is None:
         click.echo(ctx.parent.get_help())
-    else:
+    elif topic in cli.commands:
         ctx.info_name = topic
         click.echo_via_pager(cli.commands[topic].get_help(ctx))
+    else:
+        click.echo(f"Invalid command: {topic}", err=True)
+        click.echo(ctx.parent.get_help())
 
 
 def print_photo_info(photos, json=False):

tests/test_cli.py

@@ -25,6 +25,7 @@ CLI_OUTPUT_NO_SUBCOMMAND = [
     "  keywords  Print out keywords found in the Photos library.",
     "  list      Print list of Photos libraries found on the system.",
     "  persons   Print out persons (faces) found in the Photos library.",
+    "  places    Print out places found in the Photos library.",
     "  query     Query the Photos database using 1 or more search options; if",
 ]
 
@@ -122,6 +123,43 @@ def test_osxphotos():
         assert line in output
 
 
+def test_osxphotos_help_1():
+    # test help command no topic
+    import osxphotos
+    from osxphotos.__main__ import cli
+
+    runner = CliRunner()
+    result = runner.invoke(cli, ["help"])
+    output = result.output
+    assert result.exit_code == 0
+    for line in CLI_OUTPUT_NO_SUBCOMMAND:
+        assert line in output
+
+
+def test_osxphotos_help_2():
+    # test help command valid topic
+    import osxphotos
+    from osxphotos.__main__ import cli
+
+    runner = CliRunner()
+    result = runner.invoke(cli, ["help", "persons"])
+    output = result.output
+    assert result.exit_code == 0
+    assert "Print out persons (faces) found in the Photos library." in result.output
+
+
+def test_osxphotos_help_3():
+    # test help command invalid topic
+    import osxphotos
+    from osxphotos.__main__ import cli
+
+    runner = CliRunner()
+    result = runner.invoke(cli, ["help", "foo"])
+    output = result.output
+    assert result.exit_code == 0
+    assert "Invalid command: foo" in result.output
+
+
 def test_query_uuid():
     import json
     import os