config: make 'git config list --type=<X>' work

Previously, the --type=<X> argument to 'git config list' was ignored and
did nothing. Now, we add the use of format_config() to the
show_all_config() function so each key-value pair is attempted to be
parsed. This is our first use of the 'gently' parameter with a nonzero
value.

If there is an error in parsing, then the row is not output.

This is a change in behavior! We are starting to respect an option that
was previously ignored, leading to potential user confusion. This is
probably still a good option, since the --type argument did not change
behavior at all previously, so users can get the behavior they expect by
removing the --type argument or adding the --no-type argument.

Signed-off-by: Derrick Stolee <stolee@gmail.com>

Author: derrickstolee

Documentation/git-config.adoc

@@ -240,6 +240,9 @@ Valid `<type>`'s include:
   that the given value is canonicalize-able as an ANSI color, but it is written
   as-is.
 +
+If the command is in `list` mode, then the `--type <type>` argument will apply
+to each listed config value. If the value does not successfully parse in that
+format, then it will be omitted from the list.
 
 --bool::
 --int::

builtin/config.c

@@ -450,21 +450,12 @@ static int show_all_config(const char *key_, const char *value_,
 {
 	const struct config_display_options *opts = cb;
 	const struct key_value_info *kvi = ctx->kvi;
+	struct strbuf formatted = STRBUF_INIT;
 
-	if (opts->show_origin || opts->show_scope) {
-		struct strbuf buf = STRBUF_INIT;
-		if (opts->show_scope)
-			show_config_scope(opts, kvi, &buf);
-		if (opts->show_origin)
-			show_config_origin(opts, kvi, &buf);
-		/* Use fwrite as "buf" can contain \0's if "end_null" is set. */
-		fwrite(buf.buf, 1, buf.len, stdout);
-		strbuf_release(&buf);
-	}
-	if (!opts->omit_values && value_)
-		printf("%s%c%s%c", key_, opts->delim, value_, opts->term);
-	else
-		printf("%s%c", key_, opts->term);
+	if (format_config(opts, &formatted, key_, value_, kvi, 1) >= 0)
+		fwrite(formatted.buf, 1, formatted.len, stdout);
+
+	strbuf_release(&formatted);
 	return 0;
 }
 

t/t1300-config.sh

@@ -2459,9 +2459,10 @@ done
 
 cat >.git/config <<-\EOF &&
 [section]
-foo = true
+foo = True
 number = 10
 big = 1M
+path = ~/dir
 EOF
 
 test_expect_success 'identical modern --type specifiers are allowed' '
@@ -2503,6 +2504,29 @@ test_expect_success 'unset type specifiers may be reset to conflicting ones' '
 	test_cmp_config 1048576 --type=bool --no-type --type=int section.big
 '
 
+test_expect_success 'list --type=bool shows only canonicalizable bool values' '
+	cat >expect <<-EOF &&
+	section.foo=true
+	section.number=true
+	section.big=true
+	EOF
+
+	git config ${mode_prefix}list --type=bool >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'list --type=path shows only canonicalizable path values' '
+	cat >expect <<-EOF &&
+	section.foo=True
+	section.number=10
+	section.big=1M
+	section.path=$HOME/dir
+	EOF
+
+	git config ${mode_prefix}list --type=path >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success '--type rejects unknown specifiers' '
 	test_must_fail git config --type=nonsense section.foo 2>error &&
 	test_grep "unrecognized --type argument" error