Re: [PATCH v7 7/7] various *.c: use isatty(0|2), not isatty(STDIN_FILENO|STDERR_FILENO)

[Johannes Altmanninger <aclopte@gmail.com>]

nit: I'd maybe drop the "various *.c: " subject prefix. It's already
implied that the change is across the entire tree.

On Fri, Dec 17, 2021 at 05:25:02AM +0100, Ævar Arnfjörð Bjarmason wrote:
> We have over 50 uses of "isatty(1)" and "isatty(2)" in the codebase,
> and around 10 "isatty(0)", but these used the

nit: ambiguous pronouns like "these" here can trip up the reader for a
second. Maybe "three places" is clearer.

> {STDIN_FILENO,STD{OUT,ERR}_FILENO} macros in "stdlib.h" to refer to
> them.
> 
> Let's change these for consistency, and because another commit that
> would like to be based on top of this one[1] has a recipe to change
> all of these for ad-hoc testing, not needing to match these with that
> ad-hoc regex will make things easier to explain.

this sentence is quite long, and it also doesn't help that "these" refers
to something other than it did in the previous sentence.
Here's my attempt:

	Let's change these for consistency.  This makes it easier to change all
	calls to isatty() at a whim, which is useful to test some scenarios[1].

> Only one of these is
> related to the "struct progress" code which it discusses, but let's
> change all of these while we're at it.
> 
> 1. https://lore.kernel.org/git/patch-v6-8.8-bff919994b5-20211102T122507Z-avarab@gmail.com/
> 
> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
> ---
>  builtin/bisect--helper.c | 2 +-
>  builtin/bundle.c         | 2 +-
>  compat/mingw.c           | 2 +-
>  3 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
> index 28a2e6a5750..21360a4e70b 100644
> --- a/builtin/bisect--helper.c
> +++ b/builtin/bisect--helper.c
> @@ -830,7 +830,7 @@ static int bisect_autostart(struct bisect_terms *terms)
>  	fprintf_ln(stderr, _("You need to start by \"git bisect "
>  			  "start\"\n"));
>  
> -	if (!isatty(STDIN_FILENO))
> +	if (!isatty(0))
>  		return -1;
>  
>  	/*
> diff --git a/builtin/bundle.c b/builtin/bundle.c
> index 5a85d7cd0fe..df69c651753 100644
> --- a/builtin/bundle.c
> +++ b/builtin/bundle.c
> @@ -56,7 +56,7 @@ static int parse_options_cmd_bundle(int argc,
>  
>  static int cmd_bundle_create(int argc, const char **argv, const char *prefix) {
>  	int all_progress_implied = 0;
> -	int progress = isatty(STDERR_FILENO);
> +	int progress = isatty(2);
>  	struct strvec pack_opts;
>  	int version = -1;
>  	int ret;
> diff --git a/compat/mingw.c b/compat/mingw.c
> index e14f2d5f77c..7c55d0f0414 100644
> --- a/compat/mingw.c
> +++ b/compat/mingw.c
> @@ -2376,7 +2376,7 @@ int mingw_raise(int sig)
>  	switch (sig) {
>  	case SIGALRM:
>  		if (timer_fn == SIG_DFL) {
> -			if (isatty(STDERR_FILENO))
> +			if (isatty(2))
>  				fputs("Alarm clock\n", stderr);
>  			exit(128 + SIGALRM);
>  		} else if (timer_fn != SIG_IGN)
> -- 
> 2.34.1.1119.g7a3fc8778ee
>