message: Update help::help_alias() to assert the new behavior
diff: @@ -110,6 +110,20 @@ fn help_with_man_and_path(
  assert_eq!(stdout, contents);
  }
  +fn help_with_stdout_and_path(subcommand: &str, path: &Path) -> String {
  + let output = process(&cargo_exe())
  + .arg("help")
  + .arg(subcommand)
  + .env("PATH", path)
  + .exec_with_output()
  + .unwrap();
  + assert!(output.status.success());
  + let stderr = from_utf8(&output.stderr).unwrap();
  + assert_eq!(stderr, "");
  + let stdout = from_utf8(&output.stdout).unwrap();
  + stdout.to_string()
  +}
  +
  #[cargo_test]
  fn help_man() {
  // Checks that `help command` displays the man page using the given command.
  @@ -124,7 +138,8 @@ fn help_man() {
  #[cargo_test]
  fn help_alias() {
  // Check that `help some_alias` will resolve.
  - help_with_man_and_path("", "b", "build", Path::new(""));
  + let out = help_with_stdout_and_path("b", Path::new(""));
  + assert_eq!(out, "'b' is aliased to 'build'\n");
  let config = paths::root().join(".cargo/config");
  fs::create_dir_all(config.parent().unwrap()).unwrap();
  @@ -136,7 +151,8 @@ fn help_alias() {
  "#,
  )
  .unwrap();
  - help_with_man_and_path("", "my-alias", "build", Path::new(""));
  + let out = help_with_stdout_and_path("my-alias", Path::new(""));
  + assert_eq!(out, "'my-alias' is aliased to 'build --release'\n");
  }
  #[cargo_test]
  