test: add net permissions noban/download unit test coverage

to clarify/test the relationship and NetPermissions operations
involving the NetPermissionFlags PF_NOBAN and PF_DOWNLOAD.

Co-authored-by: Vasil Dimov <vd@FreeBSD.org>

src/test/netbase_tests.cpp

@@ -395,6 +395,28 @@ BOOST_AUTO_TEST_CASE(netpermissions_test)
     BOOST_CHECK(NetWhitebindPermissions::TryParse("@1.2.3.4:32", whitebindPermissions, error));
     BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_NONE);
 
+    NetWhitebindPermissions noban, noban_download, download_noban, download;
+
+    // "noban" implies "download"
+    BOOST_REQUIRE(NetWhitebindPermissions::TryParse("noban@1.2.3.4:32", noban, error));
+    BOOST_CHECK_EQUAL(noban.m_flags, NetPermissionFlags::PF_NOBAN);
+    BOOST_CHECK(NetPermissions::HasFlag(noban.m_flags, NetPermissionFlags::PF_DOWNLOAD));
+    BOOST_CHECK(NetPermissions::HasFlag(noban.m_flags, NetPermissionFlags::PF_NOBAN));
+
+    // "noban,download" is equivalent to "noban"
+    BOOST_REQUIRE(NetWhitebindPermissions::TryParse("noban,download@1.2.3.4:32", noban_download, error));
+    BOOST_CHECK_EQUAL(noban_download.m_flags, noban.m_flags);
+
+    // "download,noban" is equivalent to "noban"
+    BOOST_REQUIRE(NetWhitebindPermissions::TryParse("download,noban@1.2.3.4:32", download_noban, error));
+    BOOST_CHECK_EQUAL(download_noban.m_flags, noban.m_flags);
+
+    // "download" excludes (does not imply) "noban"
+    BOOST_REQUIRE(NetWhitebindPermissions::TryParse("download@1.2.3.4:32", download, error));
+    BOOST_CHECK_EQUAL(download.m_flags, NetPermissionFlags::PF_DOWNLOAD);
+    BOOST_CHECK(NetPermissions::HasFlag(download.m_flags, NetPermissionFlags::PF_DOWNLOAD));
+    BOOST_CHECK(!NetPermissions::HasFlag(download.m_flags, NetPermissionFlags::PF_NOBAN));
+
     // Happy path, can parse flags
     BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom,forcerelay@1.2.3.4:32", whitebindPermissions, error));
     // forcerelay should also activate the relay permission
@@ -407,7 +429,7 @@ BOOST_AUTO_TEST_CASE(netpermissions_test)
 
     // Allow dups
     BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom,relay,noban,noban@1.2.3.4:32", whitebindPermissions, error));
-    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_BLOOMFILTER | PF_RELAY | PF_NOBAN);
+    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_BLOOMFILTER | PF_RELAY | PF_NOBAN | PF_DOWNLOAD); // "noban" implies "download"
 
     // Allow empty
     BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom,relay,,noban@1.2.3.4:32", whitebindPermissions, error));
@@ -428,6 +450,8 @@ BOOST_AUTO_TEST_CASE(netpermissions_test)
     // Happy path for whitelist parsing
     BOOST_CHECK(NetWhitelistPermissions::TryParse("noban@1.2.3.4", whitelistPermissions, error));
     BOOST_CHECK_EQUAL(whitelistPermissions.m_flags, PF_NOBAN);
+    BOOST_CHECK(NetPermissions::HasFlag(whitelistPermissions.m_flags, NetPermissionFlags::PF_NOBAN));
+
     BOOST_CHECK(NetWhitelistPermissions::TryParse("bloom,forcerelay,noban,relay@1.2.3.4/32", whitelistPermissions, error));
     BOOST_CHECK_EQUAL(whitelistPermissions.m_flags, PF_BLOOMFILTER | PF_FORCERELAY | PF_NOBAN | PF_RELAY);
     BOOST_CHECK(error.empty());