route: Test trimmed netmask parsing on Darwin

route/address_darwin_test.go

@@ -42,6 +42,60 @@ var parseAddrsOnDarwinLittleEndianTests = []parseAddrsOnDarwinTest{
 			nil,
 		},
 	},
+	{
+		syscall.RTA_DST | syscall.RTA_GATEWAY | syscall.RTA_NETMASK,
+		parseKernelInetAddr,
+		[]byte{
+			0x10, 0x02, 0x00, 0x00, 0x64, 0x71, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+
+			0x14, 0x12, 0x21, 0x00, 0x01, 0x08, 0x00, 0x00,
+			0x75, 0x74, 0x75, 0x6e, 0x34, 0x33, 0x31, 0x39,
+			0x00, 0x00, 0x00, 0x00,
+
+			0x06, 0x02, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00,
+		},
+		[]Addr{
+			&Inet4Addr{IP: [4]byte{100, 113, 0, 0}},
+			&LinkAddr{Index: 33, Name: "utun4319"},
+			&Inet4Addr{IP: [4]byte{255, 255, 0, 0}},
+			nil,
+			nil,
+			nil,
+			nil,
+			nil,
+		},
+	},
+	// route -n add -inet6 fd84:1b4e:6281:: -prefixlen 48 fe80::f22f:4bff:fe09:3bff%utun4319
+	// gw fe80:0000:0000:0000:f22f:4bff:fe09:3bff
+	{
+		syscall.RTA_DST | syscall.RTA_GATEWAY | syscall.RTA_NETMASK,
+		parseKernelInetAddr,
+		[]byte{
+			0x1c, 0x1e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0xfd, 0x84, 0x1b, 0x4e, 0x62, 0x81, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00,
+
+			0x1c, 0x1e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0xfe, 0x80, 0x00, 0x21, 0x00, 0x00, 0x00, 0x00,
+			0xf2, 0x2f, 0x4b, 0xff, 0xfe, 0x09, 0x3b, 0xff,
+			0x00, 0x00, 0x00, 0x00,
+
+			0x0e, 0x1e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00,
+		},
+		[]Addr{
+			&Inet6Addr{IP: [16]byte{ 0xfd, 0x84, 0x1b, 0x4e, 0x62, 0x81 }},
+			&Inet6Addr{IP: [16]byte{ 0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf2, 0x2f, 0x4b, 0xff, 0xfe, 0x09, 0x3b, 0xff }, ZoneID: 33},
+			&Inet6Addr{IP: [16]byte{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,}},
+			nil,
+			nil,
+			nil,
+			nil,
+			nil,
+		},
+	},
 }
 
 func TestParseAddrsOnDarwin(t *testing.T) {