Help shown via no_args_is_help results in exit code 2, was 0

CHANGES.rst

@@ -56,6 +56,9 @@ Unreleased
     :issue:`2746` :pr:`2788`
 -   Add ``Choice.get_invalid_choice_message`` method for customizing the
     invalid choice message. :issue:`2621` :pr:`2622`
+-   If help is shown because ``no_args_is_help`` is enabled (defaults to ``True``
+    for groups, ``False`` for commands), the exit code is 2 instead of 0.
+    :issue:`1489` :pr:`1489`
 
 
 Version 8.1.8

src/click/core.py

@@ -24,6 +24,7 @@
 from .exceptions import ClickException
 from .exceptions import Exit
 from .exceptions import MissingParameter
+from .exceptions import NoArgsIsHelpError
 from .exceptions import UsageError
 from .formatting import HelpFormatter
 from .formatting import join_options
@@ -1156,8 +1157,7 @@ def make_context(
 
     def parse_args(self, ctx: Context, args: list[str]) -> list[str]:
         if not args and self.no_args_is_help and not ctx.resilient_parsing:
-            echo(ctx.get_help(), color=ctx.color)
-            ctx.exit()
+            raise NoArgsIsHelpError(ctx)
 
         parser = self.make_parser(ctx)
         opts, args, param_order = parser.parse_args(args=args)
@@ -1747,8 +1747,7 @@ def format_commands(self, ctx: Context, formatter: HelpFormatter) -> None:
 
     def parse_args(self, ctx: Context, args: list[str]) -> list[str]:
         if not args and self.no_args_is_help and not ctx.resilient_parsing:
-            echo(ctx.get_help(), color=ctx.color)
-            ctx.exit()
+            raise NoArgsIsHelpError(ctx)
 
         rest = super().parse_args(ctx, args)
 
@@ -1851,7 +1850,7 @@ def resolve_command(
         # place.
         if cmd is None and not ctx.resilient_parsing:
             if _split_opt(cmd_name)[0]:
-                self.parse_args(ctx, ctx.args)
+                self.parse_args(ctx, args)
             ctx.fail(_("No such command {name!r}.").format(name=original_cmd_name))
         return cmd_name if cmd else None, cmd, args[1:]
 

src/click/exceptions.py

@@ -255,6 +255,15 @@ class BadArgumentUsage(UsageError):
     """
 
 
+class NoArgsIsHelpError(UsageError):
+    def __init__(self, ctx: Context) -> None:
+        self.ctx: Context
+        super().__init__(ctx.get_help(), ctx=ctx)
+
+    def show(self, file: t.IO[t.Any] | None = None) -> None:
+        echo(self.format_message(), file=file, err=True, color=self.ctx.color)
+
+
 class FileError(ClickException):
     """Raised if a file cannot be opened."""
 

tests/test_commands.py

@@ -95,13 +95,9 @@ def long():
     )
 
 
-def test_no_args_is_help(runner):
-    @click.command(no_args_is_help=True)
-    def cli():
-        pass
-
-    result = runner.invoke(cli, [])
-    assert result.exit_code == 0
+def test_command_no_args_is_help(runner):
+    result = runner.invoke(click.Command("test", no_args_is_help=True))
+    assert result.exit_code == 2
     assert "Show this message and exit." in result.output
 
 
@@ -127,7 +123,7 @@ def foo(name):
         (["obj1"], 2, "Error: Missing command."),
         (["obj1", "--help"], 0, "Show this message and exit."),
         (["obj1", "move"], 0, "obj=obj1\nmove\n"),
-        ([], 0, "Show this message and exit."),
+        ([], 2, "Show this message and exit."),
     ],
 )
 def test_group_with_args(runner, args, exit_code, expect):