Hello, again!

This v4 addresses these two issues:

1. NUL was replaced by _NUL_ in the documentation
2. Now, the default output format of `git repo info --keys` is "lines"
   and "default" is a synonym for it. I prefer to called it "lines"
   instead of "newline" (as suggested by Patrick) because I thought that
   it would be clear to the user

Lucas Seiki Oshiro (2):
  repo: add a default output format to enum output_format
  repo: add new flag --keys to git-repo-info

 Documentation/git-repo.adoc | 33 +++++++++++++++++-----
 builtin/repo.c              | 56 ++++++++++++++++++++++++++++++++++---
 t/t1900-repo.sh             | 54 +++++++++++++++++++++++++++--------
 t/t1901-repo-structure.sh   | 22 +++++++++++++++
 4 files changed, 143 insertions(+), 22 deletions(-)

Range-diff against v3:
1:  97f8eee687 = 1:  7dabd62250 repo: add a default output format to enum output_format
2:  0c7d3bca32 ! 2:  fba621fc4f repo: add new flag --keys to git-repo-info
    @@ Documentation/git-repo.adoc: SYNOPSIS
      --------
      [synopsis]
      git repo info [--format=(default|keyvalue|nul) | -z] [--all | <key>...]
    -+git repo info --keys [--format=(default|nul) | -z]
    ++git repo info --keys [--format=(default|lines|nul) | -z]
      git repo structure [--format=(default|table|keyvalue|nul) | -z]
      
      DESCRIPTION
    @@ Documentation/git-repo.adoc: supported:
      +
      `-z` is an alias for `--format=nul`.
      
    -+`info --keys [--format=(default|nul) | -z]`::
    ++`info --keys [--format=(default|lines|nul) | -z]`::
     +	List all the available keys, one per line. The output format can be chosen
     +	through the flag `--format`. The following formats are supported:
     ++
     +`default`:::
    ++	synonym for `lines`.
    ++
    ++`lines`:::
     +	output the keys one per line.
     +
     +`nul`:::
    -+	similar to `default`, but using a NUL character after each value.
    ++	similar to `default`, but using a _NUL_ character after each value.
     +
      `structure [--format=(default|table|keyvalue|nul) | -z]`::
      	Retrieve statistics about the current repository structure. The
    @@ builtin/repo.c
      
      static const char *const repo_usage[] = {
      	"git repo info [--format=(default|keyvalue|nul) | -z] [--all | <key>...]",
    -+	"git repo info --keys [--format=(default|nul) | -z]",
    ++	"git repo info --keys [--format=(default|lines|nul) | -z]",
      	"git repo structure [--format=(default|table|keyvalue|nul) | -z]",
      	NULL
      };
    +@@ builtin/repo.c: enum output_format {
    + 	FORMAT_TABLE,
    + 	FORMAT_KEYVALUE,
    + 	FORMAT_NUL_TERMINATED,
    ++	FORMAT_LINES
    + };
    + 
    + struct field {
     @@ builtin/repo.c: static int print_all_fields(struct repository *repo,
      	return 0;
      }
    @@ builtin/repo.c: static int print_all_fields(struct repository *repo,
     +{
     +	char sep;
     +
    ++	if (format == FORMAT_DEFAULT)
    ++		format = FORMAT_LINES;
    ++
     +	switch (format) {
    -+	case FORMAT_DEFAULT:
    ++	case FORMAT_LINES:
     +		sep = '\n';
     +		break;
     +	case FORMAT_NUL_TERMINATED:
    @@ builtin/repo.c: static int print_all_fields(struct repository *repo,
      static int parse_format_cb(const struct option *opt,
      			   const char *arg, int unset UNUSED)
      {
    +@@ builtin/repo.c: static int parse_format_cb(const struct option *opt,
    + 		*format = FORMAT_KEYVALUE;
    + 	else if (!strcmp(arg, "table"))
    + 		*format = FORMAT_TABLE;
    ++	else if (!strcmp(arg, "lines"))
    ++		*format = FORMAT_LINES;
    + 	else if (!strcmp(arg, "default"))
    + 		*format = FORMAT_DEFAULT;
    + 	else
     @@ builtin/repo.c: static int cmd_repo_info(int argc, const char **argv, const char *prefix,
      {
      	enum output_format format = FORMAT_DEFAULT;
    @@ t/t1900-repo.sh: test_expect_success '--format=default resets the format' '
     +	test_cmp expect actual_all &&
     +	test_cmp expect actual_key
     +'
    ++
    ++test_expect_success 'git repo info --keys uses lines as its default output format' '
    ++	git repo info --keys --format=lines >expect &&
    ++	git repo info --keys --format=default >actual_explicit &&
    ++	git repo info --keys >actual_implicit &&
    ++	test_cmp expect actual_explicit &&
    ++	test_cmp expect actual_implicit
    ++'
     +
      test_done
-- 
2.50.1 (Apple Git-155)