From bd156836703e52166c282a0fea50a45498cfabdd Mon Sep 17 00:00:00 2001
From: "Alex Xu (Hello71)" <alex_y_xu@yahoo.ca>
Date: Sat, 7 Aug 2021 08:31:31 -0400
Subject: [PATCH] add: warn when creating empty virtual packages

see https://gitlab.alpinelinux.org/alpine/aports/-/issues/11736

[TT: minor stylistic change]
---
 src/app_add.c    | 2 ++
 test/basic8.test | 1 +
 2 files changed, 3 insertions(+)

diff --git a/src/app_add.c b/src/app_add.c
index 345fd7a..214bf67 100644
--- a/src/app_add.c
+++ b/src/app_add.c
@@ -147,6 +147,8 @@ static int add_main(void *ctx, struct apk_ctx *ac, struct apk_string_array *args
 
 		virtdep.result_mask = APK_VERSION_EQUAL;
 		virtdep.version = virtpkg->version;
+
+		if (!args->num) apk_warn(out, "creating empty virtual package");
 	}
 
 	foreach_array_item(parg, args) {
diff --git a/test/basic8.test b/test/basic8.test
index 19d3964..0042371 100644
--- a/test/basic8.test
+++ b/test/basic8.test
@@ -2,5 +2,6 @@
 --no-network
 add -t .virtual
 @EXPECT
+WARNING: creating empty virtual package
 (1/1) Installing .virtual (20190603.131426)
 OK: 0 MiB in 0 packages