Re: [PATCH] switch: fix errors and comments related to -c and -C

[Taylor Blau <me@ttaylorr.com>]

Hi Denton,

On Wed, Apr 29, 2020 at 05:00:19AM -0400, Denton Liu wrote:
> In d787d311db (checkout: split part of it to new command 'switch',
> 2019-03-29), the `git switch` command was created by extracting the
> common functionality of cmd_checkout() in checkout_main(). However, in
> b7b5fce270 (switch: better names for -b and -B, 2019-03-29), these
> the branch creation and force creation options for 'switch' were changed
> to -c and -C, respectively. As a result of this, error messages and
> comments that previously referred to `-b` and `-B` became invalid for
> `git switch`.
>
> For comments that refer to `-b` and `-B`, add `-c` and `-C` to the
> comment.

I had to read this sentence a couple of times more than I would have
liked to in order to grok it fully. Would it be perhaps clearer as:

  Update comments in 'cmd_checkout()' that mention `-b` or `-B` to
  instead refer to `-c` or `-C` when invoked from 'git switch'.

?

> For error messages that refer to `-b`, introduce `enum cmd_variant` and
> use it to differentiate between `checkout` and `switch` when printing
> out error messages.
>
> An alternative implementation which was considered involved inserting
> option name variants into a struct which is passed in by each command
> variant. Even though this approach is more general and could be
> applicable for future differing option names, it seemed like an
> over-engineered solution when the current pair of options are the only
> differing ones. We should probably avoid adding options which have
> different names anyway.

Yeah, I don't think we should spend much time trying to figure out a
general solution here when these are the only differing pair.

> Reported-by: Robert Simpson <no-reply@MailScreen.com>
> Signed-off-by: Denton Liu <liu.denton@gmail.com>
> ---
>
> Notes:
>     Robert, is the email listed above correct? If not, please let me know
>     which email to use. (I hope that this reaches you somehow.)

I'll be shocked if this is his real email address ;).

>  builtin/checkout.c | 26 ++++++++++++++++++--------
>  1 file changed, 18 insertions(+), 8 deletions(-)
>
> diff --git a/builtin/checkout.c b/builtin/checkout.c
> index 8bc94d392b..0ca74cde08 100644
> --- a/builtin/checkout.c
> +++ b/builtin/checkout.c
> @@ -1544,9 +1544,16 @@ static struct option *add_checkout_path_options(struct checkout_opts *opts,
>  	return newopts;
>  }
>
> +enum cmd_variant {
> +	CMD_CHECKOUT,
> +	CMD_SWITCH,
> +	CMD_RESTORE
> +};
> +
>  static int checkout_main(int argc, const char **argv, const char *prefix,
>  			 struct checkout_opts *opts, struct option *options,
> -			 const char * const usagestr[])
> +			 const char * const usagestr[],
> +			 enum cmd_variant variant)
>  {
>  	struct branch_info new_branch_info;
>  	int parseopt_flags = 0;
> @@ -1586,7 +1593,9 @@ static int checkout_main(int argc, const char **argv, const char *prefix,
>  	}
>
>  	if ((!!opts->new_branch + !!opts->new_branch_force + !!opts->new_orphan_branch) > 1)
> -		die(_("-b, -B and --orphan are mutually exclusive"));
> +		die(variant == CMD_CHECKOUT ?
> +				_("-b, -B and --orphan are mutually exclusive") :
> +				_("-c, -C and --orphan are mutually exclusive"));

Hmm. Do we need to generate an extra string for translation here? If the
string was instead:

  _("%s and --orphan are mutually exclusive")

where the first format string is filled in something like:

  die(_("%s and --orphan are mutually exclusive"),
      variant == CMD_CHECKOUT ? "-b, -B" : "-c, -C");

may save translators some work.

>  	if (opts->overlay_mode == 1 && opts->patch_mode)
>  		die(_("-p and --overlay are mutually exclusive"));
> @@ -1614,7 +1623,7 @@ static int checkout_main(int argc, const char **argv, const char *prefix,
>  	/*
>  	 * From here on, new_branch will contain the branch to be checked out,
>  	 * and new_branch_force and new_orphan_branch will tell us which one of
> -	 * -b/-B/--orphan is being used.
> +	 * -b/-B/-c/-C/--orphan is being used.
>  	 */
>  	if (opts->new_branch_force)
>  		opts->new_branch = opts->new_branch_force;
> @@ -1622,7 +1631,7 @@ static int checkout_main(int argc, const char **argv, const char *prefix,
>  	if (opts->new_orphan_branch)
>  		opts->new_branch = opts->new_orphan_branch;
>
> -	/* --track without -b/-B/--orphan should DWIM */
> +	/* --track without -b/-B/--orphan for checkout or -c/-C/--orphan for switch should DWIM */

This line is getting a little long. Would you mind wrapping this as a
multi-line comment instead?

>  	if (opts->track != BRANCH_TRACK_UNSPECIFIED && !opts->new_branch) {
>  		const char *argv0 = argv[0];
>  		if (!argc || !strcmp(argv0, "--"))
> @@ -1631,7 +1640,8 @@ static int checkout_main(int argc, const char **argv, const char *prefix,
>  		skip_prefix(argv0, "remotes/", &argv0);
>  		argv0 = strchr(argv0, '/');
>  		if (!argv0 || !argv0[1])
> -			die(_("missing branch name; try -b"));
> +			die(_("missing branch name; try -%c"),
> +					variant == CMD_CHECKOUT ? 'b' : 'c');
>  		opts->new_branch = argv0 + 1;
>  	}
>
> @@ -1785,7 +1795,7 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
>  	options = add_checkout_path_options(&opts, options);
>
>  	ret = checkout_main(argc, argv, prefix, &opts,
> -			    options, checkout_usage);
> +			    options, checkout_usage, CMD_CHECKOUT);
>  	FREE_AND_NULL(options);
>  	return ret;
>  }
> @@ -1823,7 +1833,7 @@ int cmd_switch(int argc, const char **argv, const char *prefix)
>  	options = add_common_switch_branch_options(&opts, options);
>
>  	ret = checkout_main(argc, argv, prefix, &opts,
> -			    options, switch_branch_usage);
> +			    options, switch_branch_usage, CMD_SWITCH);
>  	FREE_AND_NULL(options);
>  	return ret;
>  }
> @@ -1860,7 +1870,7 @@ int cmd_restore(int argc, const char **argv, const char *prefix)
>  	options = add_checkout_path_options(&opts, options);
>
>  	ret = checkout_main(argc, argv, prefix, &opts,
> -			    options, restore_usage);
> +			    options, restore_usage, CMD_RESTORE);
>  	FREE_AND_NULL(options);
>  	return ret;
>  }
> --
> 2.26.2.548.gbb00c8a0a9

All of the rest makes sense, thanks.

Thanks,
Taylor