No tool provided needs to be handled explicitly. Add missing smoke test for tool's help.

Author: wenzeslaus

python/grass/app/cli.py

@@ -121,7 +121,7 @@ def main(args=None, program=None):
         "run",
         help="run a tool",
         add_help=False,
-        epilog="Tool name is followed by it parameters.",
+        epilog="Tool name is followed by its parameters.",
     )
     run_subparser.add_argument("tool", type=str, nargs="?", help="name of a tool")
     run_subparser.add_argument("--help", action="store_true")
@@ -177,5 +177,9 @@ def main(args=None, program=None):
         if parsed_args.tool is None and parsed_args.help:
             run_subparser.print_help()
             return 0
+        if parsed_args.tool is None:
+            run_subparser.print_usage()
+            # argparse gives 2 without parameters, so we behave the same.
+            return 2
         return parsed_args.func(parsed_args, other_args, print_help=parsed_args.help)
     return parsed_args.func(parsed_args)

python/grass/app/tests/grass_app_cli_test.py

@@ -6,27 +6,50 @@
 
 
 def test_cli_help_runs():
+    """Check help the main command"""
     with pytest.raises(SystemExit) as exception:
         main(["--help"])
     assert exception.value.code == 0
 
 
 @pytest.mark.skipif(sys.platform.startswith("win"), reason="No man on Windows")
 def test_man_subcommand_runs():
+    """Check that man subcommand runs without an error"""
     assert main(["man", "g.region"]) == 0
 
 
+def test_subcommand_man_no_page():
+    """argparse gives 2 without parameters"""
+    with pytest.raises(SystemExit) as exception:
+        main(["man"])
+    assert exception.value.code == 2
+
+
 def test_subcommand_run_help():
+    """Check help of a subcommand"""
     assert main(["run", "--help"]) == 0
 
 
+def test_subcommand_run_no_tool():
+    """argparse gives 2 without parameters"""
+    assert main(["run"]) == 2
+
+
+def test_subcommand_run_tool_help():
+    """Check help of a tool"""
+    assert main(["run", "g.region", "--help"]) == 0
+
+
 def test_subcommand_run_tool_special_flag():
+    """Check that a special flag is supported"""
     assert main(["run", "g.region", "--interface-description"]) == 0
 
 
 def test_subcommand_run_tool_regular_run():
+    """Check that a tool runs without error"""
     assert main(["run", "g.region", "-p"]) == 0
 
 
 def test_subcommand_run_tool_failure_run():
+    """Check that a tool produces non-zero return code"""
     assert main(["run", "g.region", "raster=does_not_exist"]) == 1