Improve CLI help handling for run command

Updated the `run` command so that `--help` is passed to the subcommand if there is one.

Author: bm371613

src/dotenv/cli.py

@@ -156,7 +156,7 @@ def unset(ctx: click.Context, key: Any) -> None:
         sys.exit(1)
 
 
-@cli.command(context_settings={"ignore_unknown_options": True})
+@cli.command(context_settings={"ignore_unknown_options": True}, add_help_option=False, no_args_is_help=True)
 @click.pass_context
 @click.option(
     "--override/--no-override",
@@ -180,6 +180,9 @@ def run(ctx: click.Context, override: bool, commandline: List[str]) -> None:
     if not commandline:
         click.echo("No command given.")
         sys.exit(1)
+    if len(commandline) == 1 and commandline[0] in ["-h", "--help"]:
+        click.echo(ctx.get_help())
+        sys.exit(0)
     run_command(commandline, dotenv_as_dict)
 
 

tests/test_cli.py

@@ -1,4 +1,6 @@
 import os
+import subprocess
+import sys
 from pathlib import Path
 from typing import Optional
 
@@ -249,3 +251,19 @@ def test_run_with_version(cli):
 
     assert result.exit_code == 0
     assert result.output.strip().endswith(__version__)
+
+
+def test_run_subcommand_with_help_uses_subcommand_help(cli, dotenv_path):
+    dotenv_path.write_text("a=b")
+    output = sh.dotenv("--file", dotenv_path, "run", "printenv", "--help")
+
+    assert "dotenv run" not in output
+    expected_help_output = subprocess.check_output(["printenv", "--help"]).decode("utf-8")
+    assert output == expected_help_output
+
+
+def test_run_with_just_help_show_help(cli, dotenv_path):
+    dotenv_path.write_text("a=b")
+    output = sh.dotenv("--file", dotenv_path, "run", "--help")
+
+    assert "dotenv run" in output