diff mbox series

[4/7] built-in stash: use the built-in `git add -p` if so configured

Message ID 40c00302f67ed927317fb5955e13690328e2f4e8.1576579264.git.gitgitgadget@gmail.com (mailing list archive)
State New, archived
Headers show
Series stash/reset/checkout -p: optionally use the add --patch backend written in pure C | expand

Commit Message

Linus Arver via GitGitGadget Dec. 17, 2019, 10:41 a.m. UTC 
From: Johannes Schindelin <johannes.schindelin@gmx.de>

The scripted version of `git stash` called directly into the Perl script
`git-add--interactive.perl`, and this was faithfully converted to C.

However, we have a much better way to do this now: call the internal API
directly, which will now incidentally also respect the
`add.interactive.useBuiltin` setting. Let's just do this.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 builtin/stash.c | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

Comments

Junio C Hamano Dec. 17, 2019, 8:19 p.m. UTC | #1 
"Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
writes:

> diff --git a/builtin/stash.c b/builtin/stash.c
> index 4e806176b0..2dafd97766 100644
> --- a/builtin/stash.c
> +++ b/builtin/stash.c
> @@ -999,9 +999,9 @@ static int stash_patch(struct stash_info *info, const struct pathspec *ps,
>  {
>  	int ret = 0;
>  	struct child_process cp_read_tree = CHILD_PROCESS_INIT;
> -	struct child_process cp_add_i = CHILD_PROCESS_INIT;
>  	struct child_process cp_diff_tree = CHILD_PROCESS_INIT;
>  	struct index_state istate = { NULL };
> +	char *old_index_env = NULL, *old_repo_index_file;
>  
>  	remove_path(stash_index_path.buf);
>  

Together with the previous step, it makes sense.  Earlier we always
spawned the scripted version.  Now we first give control to the C
code and allow it to punt to the scripted version unless it is told
to take control with USE_BUILTIN.

> @@ -1015,16 +1015,19 @@ static int stash_patch(struct stash_info *info, const struct pathspec *ps,
>  	}
>  
>  	/* Find out what the user wants. */
> -	cp_add_i.git_cmd = 1;
> -	argv_array_pushl(&cp_add_i.args, "add--interactive", "--patch=stash",
> -			 "--", NULL);
> -	add_pathspecs(&cp_add_i.args, ps);
> -	argv_array_pushf(&cp_add_i.env_array, "GIT_INDEX_FILE=%s",
> -			 stash_index_path.buf);
> -	if (run_command(&cp_add_i)) {
> -		ret = -1;
> -		goto done;
> -	}
> +	old_repo_index_file = the_repository->index_file;
> +	the_repository->index_file = stash_index_path.buf;
> +	old_index_env = xstrdup_or_null(getenv(INDEX_ENVIRONMENT));
> +	setenv(INDEX_ENVIRONMENT, the_repository->index_file, 1);
> +
> +	ret = run_add_interactive(NULL, "--patch=stash", ps);
> +
> +	the_repository->index_file = old_repo_index_file;
> +	if (old_index_env && *old_index_env)
> +		setenv(INDEX_ENVIRONMENT, old_index_env, 1);
> +	else
> +		unsetenv(INDEX_ENVIRONMENT);
> +	FREE_AND_NULL(old_index_env);

OK.  I suspect that, as we move more stuff that used to be an
external call with one-shot environment assignments like this to an
internall call, we'd see patterns of "save away the state of this
and that environment variables, then replace them with these values"
paired with "now restore the state of those environment variables".

We might eventually want to add a helper for doing so easily, which
may make the caller look like

	extern void save_environment(struct saved_env *, ...);

	struct saved_env env;
	save_environment(&env, 
			INDEX_ENVIRONMENT, the_repository->index_file,
			NULL /* end of "VAR, val" tuples */);

	ret = run_add_interactive(NULL, "--patch=stash", ps);

        restore_environment(&env);

It might (or might not) be premature to introduce such a helper at
this stage in the series, though.

Thanks.
Johannes Schindelin Dec. 21, 2019, 9:26 p.m. UTC | #2 
Hi Junio,

On Tue, 17 Dec 2019, Junio C Hamano wrote:

> "Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
> writes:
>
> > diff --git a/builtin/stash.c b/builtin/stash.c
> > index 4e806176b0..2dafd97766 100644
> > --- a/builtin/stash.c
> > +++ b/builtin/stash.c
> > @@ -999,9 +999,9 @@ static int stash_patch(struct stash_info *info, const struct pathspec *ps,
> >  {
> >  	int ret = 0;
> >  	struct child_process cp_read_tree = CHILD_PROCESS_INIT;
> > -	struct child_process cp_add_i = CHILD_PROCESS_INIT;
> >  	struct child_process cp_diff_tree = CHILD_PROCESS_INIT;
> >  	struct index_state istate = { NULL };
> > +	char *old_index_env = NULL, *old_repo_index_file;
> >
> >  	remove_path(stash_index_path.buf);
> >
>
> Together with the previous step, it makes sense.  Earlier we always
> spawned the scripted version.  Now we first give control to the C
> code and allow it to punt to the scripted version unless it is told
> to take control with USE_BUILTIN.
>
> > @@ -1015,16 +1015,19 @@ static int stash_patch(struct stash_info *info, const struct pathspec *ps,
> >  	}
> >
> >  	/* Find out what the user wants. */
> > -	cp_add_i.git_cmd = 1;
> > -	argv_array_pushl(&cp_add_i.args, "add--interactive", "--patch=stash",
> > -			 "--", NULL);
> > -	add_pathspecs(&cp_add_i.args, ps);
> > -	argv_array_pushf(&cp_add_i.env_array, "GIT_INDEX_FILE=%s",
> > -			 stash_index_path.buf);
> > -	if (run_command(&cp_add_i)) {
> > -		ret = -1;
> > -		goto done;
> > -	}
> > +	old_repo_index_file = the_repository->index_file;
> > +	the_repository->index_file = stash_index_path.buf;
> > +	old_index_env = xstrdup_or_null(getenv(INDEX_ENVIRONMENT));
> > +	setenv(INDEX_ENVIRONMENT, the_repository->index_file, 1);
> > +
> > +	ret = run_add_interactive(NULL, "--patch=stash", ps);
> > +
> > +	the_repository->index_file = old_repo_index_file;
> > +	if (old_index_env && *old_index_env)
> > +		setenv(INDEX_ENVIRONMENT, old_index_env, 1);
> > +	else
> > +		unsetenv(INDEX_ENVIRONMENT);
> > +	FREE_AND_NULL(old_index_env);
>
> OK.  I suspect that, as we move more stuff that used to be an
> external call with one-shot environment assignments like this to an
> internall call, we'd see patterns of "save away the state of this
> and that environment variables, then replace them with these values"
> paired with "now restore the state of those environment variables".
>
> We might eventually want to add a helper for doing so easily, which
> may make the caller look like
>
> 	extern void save_environment(struct saved_env *, ...);
>
> 	struct saved_env env;
> 	save_environment(&env,
> 			INDEX_ENVIRONMENT, the_repository->index_file,
> 			NULL /* end of "VAR, val" tuples */);
>
> 	ret = run_add_interactive(NULL, "--patch=stash", ps);
>
>         restore_environment(&env);
>
> It might (or might not) be premature to introduce such a helper at
> this stage in the series, though.

To be honest, I would rather have this at a different layer: I'd like
`run_add_interactive()` to take an optional path to the index, to be able
to override the default `<gitdir>/index`.

But that requires either quite a lot of changes to the Perl script, or it
needs to wait until the built-in version of `git add -p` stabilized enough
to allow retiring the Perl script.

I kinda aimed for the latter solution.

Ciao,
Dscho
diff mbox series

Patch

diff --git a/builtin/stash.c b/builtin/stash.c
index 4e806176b0..2dafd97766 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -999,9 +999,9 @@  static int stash_patch(struct stash_info *info, const struct pathspec *ps,
 {
 	int ret = 0;
 	struct child_process cp_read_tree = CHILD_PROCESS_INIT;
-	struct child_process cp_add_i = CHILD_PROCESS_INIT;
 	struct child_process cp_diff_tree = CHILD_PROCESS_INIT;
 	struct index_state istate = { NULL };
+	char *old_index_env = NULL, *old_repo_index_file;
 
 	remove_path(stash_index_path.buf);
 
@@ -1015,16 +1015,19 @@  static int stash_patch(struct stash_info *info, const struct pathspec *ps,
 	}
 
 	/* Find out what the user wants. */
-	cp_add_i.git_cmd = 1;
-	argv_array_pushl(&cp_add_i.args, "add--interactive", "--patch=stash",
-			 "--", NULL);
-	add_pathspecs(&cp_add_i.args, ps);
-	argv_array_pushf(&cp_add_i.env_array, "GIT_INDEX_FILE=%s",
-			 stash_index_path.buf);
-	if (run_command(&cp_add_i)) {
-		ret = -1;
-		goto done;
-	}
+	old_repo_index_file = the_repository->index_file;
+	the_repository->index_file = stash_index_path.buf;
+	old_index_env = xstrdup_or_null(getenv(INDEX_ENVIRONMENT));
+	setenv(INDEX_ENVIRONMENT, the_repository->index_file, 1);
+
+	ret = run_add_interactive(NULL, "--patch=stash", ps);
+
+	the_repository->index_file = old_repo_index_file;
+	if (old_index_env && *old_index_env)
+		setenv(INDEX_ENVIRONMENT, old_index_env, 1);
+	else
+		unsetenv(INDEX_ENVIRONMENT);
+	FREE_AND_NULL(old_index_env);
 
 	/* State of the working tree. */
 	if (write_index_as_tree(&info->w_tree, &istate, stash_index_path.buf, 0,