Re: [PATCH v5 0/2] Conditional config includes based on remote URL

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

On Thu, Dec 02 2021, Jonathan Tan wrote:

> Thanks, Junio, for your comments. I think the code is more clearly laid                                  
> out now.                                                                                                 
>                                                                                                          
> The main changes from v4 are that I've maintained the existing code
> structure more, and changed the keyword used to something that hopefully
> will be more forwards compatible. I've also updated the documentation to
> explain the forwards compatibility idea.

I read through this and came up with the below as a proposed squash-in
just while reading through it. These may or may not help. Changes:

 * There was some needless "$(pwd)" in the tests
 * Inlining the "remote_urls" in the struct makes its management easier;
   and the free/NULL checks just check .nr now, and string_list_clear() can be
   unconditional.
 * Created a include_by_remote_url() function. Makes the overall diff smaller
   since you don't need to add braces to everything in include_condition_is_true()

Other comments (not related to the below):

 * It would be nice if e.g. the "includeIf.hasconfig:remote.*.url globs" test
   were split up by condition, but maybe that's a hassle (would need a small helper).

   Just something that would have helped while hacking on this, i.e. now most of it
   was an all-or-nothing failure & peek at the trace output

 * Your last test appears to entirely forbid recursion. I.e. we die if you include config
   which in turn tries to use this include mechanism, right?

   That's probably wise, and it is explicitly documented.

   But as far as the documentation about this being a forward-compatible facility, do we
   think that this limitation would apply to any future config key? I.e. if I include based
   on "user.email" nothing in that to-be-included can set user.email?

   That's probably OK, just wondering. In any case it can always be expanded later on.

diff --git a/config.c b/config.c
index 39ac38e0e78..91b0a328e59 100644
--- a/config.c
+++ b/config.c
@@ -130,9 +130,11 @@ struct config_include_data {
 	/*
 	 * All remote URLs discovered when reading all config files.
 	 */
-	struct string_list *remote_urls;
+	struct string_list remote_urls;
 };
-#define CONFIG_INCLUDE_INIT { 0 }
+#define CONFIG_INCLUDE_INIT { \
+	.remote_urls = STRING_LIST_INIT_DUP, \
+}
 
 static int git_config_include(const char *var, const char *value, void *data);
 
@@ -340,9 +342,7 @@ static void populate_remote_urls(struct config_include_data *inc)
 	current_config_kvi = NULL;
 	current_parsing_scope = 0;
 
-	inc->remote_urls = xmalloc(sizeof(*inc->remote_urls));
-	string_list_init_dup(inc->remote_urls);
-	config_with_options(add_remote_url, inc->remote_urls, inc->config_source, &opts);
+	config_with_options(add_remote_url, &inc->remote_urls, inc->config_source, &opts);
 
 	cf = store_cf;
 	current_config_kvi = store_kvi;
@@ -381,26 +381,31 @@ static int at_least_one_url_matches_glob(const char *glob, int glob_len,
 	return found;
 }
 
+static int include_by_remote_url(struct config_include_data *inc,
+				 const char *cond, size_t cond_len)
+{
+	if (inc->opts->unconditional_remote_url)
+		return 1;
+	if (!inc->remote_urls.nr)
+		populate_remote_urls(inc);
+	return at_least_one_url_matches_glob(cond, cond_len,
+					     &inc->remote_urls);
+}
+
 static int include_condition_is_true(struct config_include_data *inc,
 				     const char *cond, size_t cond_len)
 {
 	const struct config_options *opts = inc->opts;
 
-	if (skip_prefix_mem(cond, cond_len, "gitdir:", &cond, &cond_len)) {
+	if (skip_prefix_mem(cond, cond_len, "gitdir:", &cond, &cond_len))
 		return include_by_gitdir(opts, cond, cond_len, 0);
-	} else if (skip_prefix_mem(cond, cond_len, "gitdir/i:", &cond, &cond_len)) {
+	else if (skip_prefix_mem(cond, cond_len, "gitdir/i:", &cond, &cond_len))
 		return include_by_gitdir(opts, cond, cond_len, 1);
-	} else if (skip_prefix_mem(cond, cond_len, "onbranch:", &cond, &cond_len)) {
+	else if (skip_prefix_mem(cond, cond_len, "onbranch:", &cond, &cond_len))
 		return include_by_branch(cond, cond_len);
-	} else if (skip_prefix_mem(cond, cond_len, "hasconfig:remote.*.url:", &cond,
-				   &cond_len)) {
-		if (inc->opts->unconditional_remote_url)
-			return 1;
-		if (!inc->remote_urls)
-			populate_remote_urls(inc);
-		return at_least_one_url_matches_glob(cond, cond_len,
-						     inc->remote_urls);
-	}
+	else if (skip_prefix_mem(cond, cond_len, "hasconfig:remote.*.url:", &cond,
+				   &cond_len))
+		return include_by_remote_url(inc, cond, cond_len);
 
 	/* unknown conditionals are always false */
 	return 0;
@@ -2061,10 +2066,7 @@ int config_with_options(config_fn_t fn, void *data,
 		ret = do_git_config_sequence(opts, fn, data);
 	}
 
-	if (inc.remote_urls) {
-		string_list_clear(inc.remote_urls, 0);
-		FREE_AND_NULL(inc.remote_urls);
-	}
+	string_list_clear(&inc.remote_urls, 0);
 	return ret;
 }
 
diff --git a/t/t1300-config.sh b/t/t1300-config.sh
index 0f7bae31b4b..8310562b842 100755
--- a/t/t1300-config.sh
+++ b/t/t1300-config.sh
@@ -2391,11 +2391,11 @@ test_expect_success 'includeIf.hasconfig:remote.*.url' '
 	git init hasremoteurlTest &&
 	test_when_finished "rm -rf hasremoteurlTest" &&
 
-	cat >"$(pwd)"/include-this <<-\EOF &&
+	cat >include-this <<-\EOF &&
 	[user]
 		this = this-is-included
 	EOF
-	cat >"$(pwd)"/dont-include-that <<-\EOF &&
+	cat >dont-include-that <<-\EOF &&
 	[user]
 		that = that-is-not-included
 	EOF
@@ -2419,7 +2419,7 @@ test_expect_success 'includeIf.hasconfig:remote.*.url respects last-config-wins'
 	git init hasremoteurlTest &&
 	test_when_finished "rm -rf hasremoteurlTest" &&
 
-	cat >"$(pwd)"/include-two-three <<-\EOF &&
+	cat >include-two-three <<-\EOF &&
 	[user]
 		two = included-config
 		three = included-config
@@ -2453,11 +2453,11 @@ test_expect_success 'includeIf.hasconfig:remote.*.url globs' '
 	git init hasremoteurlTest &&
 	test_when_finished "rm -rf hasremoteurlTest" &&
 
-	printf "[user]\ndss = yes\n" >"$(pwd)/double-star-start" &&
-	printf "[user]\ndse = yes\n" >"$(pwd)/double-star-end" &&
-	printf "[user]\ndsm = yes\n" >"$(pwd)/double-star-middle" &&
-	printf "[user]\nssm = yes\n" >"$(pwd)/single-star-middle" &&
-	printf "[user]\nno = no\n" >"$(pwd)/no" &&
+	printf "[user]\ndss = yes\n" >double-star-start &&
+	printf "[user]\ndse = yes\n" >double-star-end &&
+	printf "[user]\ndsm = yes\n" >double-star-middle &&
+	printf "[user]\nssm = yes\n" >single-star-middle &&
+	printf "[user]\nno = no\n" >no &&
 
 	cat >>hasremoteurlTest/.git/config <<-EOF &&
 	[remote "foo"]
@@ -2491,7 +2491,7 @@ test_expect_success 'includeIf.hasconfig:remote.*.url forbids remote url in such
 	git init hasremoteurlTest &&
 	test_when_finished "rm -rf hasremoteurlTest" &&
 
-	cat >"$(pwd)"/include-with-url <<-\EOF &&
+	cat >include-with-url <<-\EOF &&
 	[remote "bar"]
 		url = bar
 	EOF