hid: port IRC tests from liberty, fix tag parsing

xS/main.go

@@ -420,7 +420,7 @@ func ircFnmatch(pattern string, s string) bool {
 }
 
 var reMsg = regexp.MustCompile(
-	`^(@[^ ]* +)?(?::([^! ]*)(?:!([^@]*)@([^ ]*))? +)?([^ ]+)(.*)?$`)
+	`^(?:@([^ ]*) +)?(?::([^! ]*)(?:!([^@]*)@([^ ]*))? +)?([^ ]+)(.*)?$`)
 var reArgs = regexp.MustCompile(`:.*| [^: ][^ ]*`)
 
 type message struct {

xS/main_test.go

@@ -137,3 +137,32 @@ func TestDetectTLS(t *testing.T) {
 		}
 	})
 }
+
+func TestIRC(t *testing.T) {
+	msg := ircParseMessage(
+		`@first=a\:\s\r\n\\;2nd :srv hi there :good m8 :how are you?`)
+
+	if !reflect.DeepEqual(msg.tags, map[string]string{
+		"first": "a; \r\n\\",
+		"2nd":   "",
+	}) {
+		t.Error("tags parsed incorrectly")
+	}
+
+	if msg.nick != "srv" || msg.user != "" || msg.host != "" {
+		t.Error("server name parsed incorrectly")
+	}
+	if msg.command != "hi" {
+		t.Error("command name parsed incorrectly")
+	}
+	if !reflect.DeepEqual(msg.params,
+		[]string{"there", "good m8 :how are you?"}) {
+		t.Error("params parsed incorrectly")
+	}
+
+	if !ircEqual("[fag]^", "{FAG}~") {
+		t.Error("string case comparison not according to RFC 2812")
+	}
+
+	// TODO: More tests.
+}