On 10/11/2019 6:27 PM, Elijah Newren wrote:

On Mon, Oct 7, 2019 at 1:08 PM Derrick Stolee via GitGitGadget
[off-list ref] wrote:

quoted

From: Derrick Stolee <redacted>

The 'git sparse-checkout set' subcommand takes a list of patterns
and places them in the sparse-checkout file. Then, it updates the
working directory to match those patterns. For a large list of
patterns, the command-line call can get very cumbersome.

Add a '--stdin' option to instead read patterns over standard in.

Signed-off-by: Derrick Stolee <redacted>
---
 builtin/sparse-checkout.c          | 40 ++++++++++++++++++++++++++++--
 t/t1091-sparse-checkout-builtin.sh | 27 ++++++++++++++++++++
 2 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/builtin/sparse-checkout.c b/builtin/sparse-checkout.c
index 52d4f832f3..68f3d8433e 100644
--- a/builtin/sparse-checkout.c
+++ b/builtin/sparse-checkout.c

@@ -145,6 +145,11 @@ static int write_patterns_and_update(struct pattern_list *pl)
        char *sparse_filename;
        FILE *fp;

+       if (!core_apply_sparse_checkout) {
+               warning(_("core.sparseCheckout is disabled, so changes to the sparse-checkout file will have no effect"));
+               warning(_("run 'git sparse-checkout init' to enable the sparse-checkout feature"));
+       }
+
        sparse_filename = get_sparse_checkout_filename();
        fp = fopen(sparse_filename, "w");
        write_patterns_to_file(fp, pl);

@@ -154,16 +159,47 @@ static int write_patterns_and_update(struct pattern_list *pl)
        return update_working_directory();
 }

+static char const * const builtin_sparse_checkout_set_usage[] = {
+       N_("git sparse-checkout set [--stdin|<patterns>]"),
+       NULL
+};
+
+static struct sparse_checkout_set_opts {
+       int use_stdin;
+} set_opts;
+
 static int sparse_checkout_set(int argc, const char **argv, const char *prefix)
 {
        static const char *empty_base = "";
        int i;
        struct pattern_list pl;
        int result;
+
+       static struct option builtin_sparse_checkout_set_options[] = {
+               OPT_BOOL(0, "stdin", &set_opts.use_stdin,
+                        N_("read patterns from standard in")),
+               OPT_END(),
+       };
+
        memset(&pl, 0, sizeof(pl));

-       for (i = 1; i < argc; i++)
-               add_pattern(argv[i], empty_base, 0, &pl, 0);
+       argc = parse_options(argc, argv, prefix,
+                            builtin_sparse_checkout_set_options,
+                            builtin_sparse_checkout_set_usage,
+                            PARSE_OPT_KEEP_UNKNOWN);

Does this mean users can also spell it 'git sparse-checkout --stdin
set', instead of the expected 'git sparse-checkout set --stdin'?

No, because the parse_options() inside cmd_sparse_checkout() parses until
it doesn't recognize an option. ('stdin' in your example). After we "consume"
the subcommand "set", we call this method and the parse_options() can then
read the '--stdin'.

Here is the output from my local command of 'git sparse-checkout --stdin set'
at this commit:

	$ ./git sparse-checkout --stdin set
	error: unknown option `stdin'
	usage: git sparse-checkout [init|list|set] <options>

Thanks,
-Stolee