Annotate crossposted messages with their origin

d2m/converters/message-to-event.js

@@ -194,6 +194,12 @@ async function messageToEvent(message, guild, options = {}, di) {
 			html = "* " + html
 		}
 
+		const flags = message.flags || 0
+		if (flags & 2) {
+			body = `[🔀 ${message.author.username}]\n` + body
+			html = `🔀 <strong>${message.author.username}</strong><br>` + html
+		}
+
 		// Fallback body/formatted_body for replies
 		// This branch is optional - do NOT change anything apart from the reply fallback, since it may not be run
 		if (repliedToEventRow && options.includeReplyFallback !== false) {

d2m/converters/message-to-event.test.js

@@ -490,3 +490,15 @@ test("message2event: emoji triple long name", async t => {
 			+ '<img data-mx-emoticon height="32" src="mxc://cadence.moe/scfRIDOGKWFDEBjVXocWYQHik" title=":brillillillilliant_move:" alt=":brillillillilliant_move:">'
 	}])
 })
+
+test("message2event: crossposted announcements say where they are crossposted from", async t => {
+	const events = await messageToEvent(data.special_message.crosspost_announcement, data.guild.general, {})
+	t.deepEqual(events, [{
+		$type: "m.room.message",
+		"m.mentions": {},
+		msgtype: "m.text",
+		body: "[🔀 Chewey Bot Official Server #announcements]\nAll text based commands are now inactive on Chewey Bot\nTo continue using commands you'll need to use them as slash commands",
+		format: "org.matrix.custom.html",
+		formatted_body: "🔀 <strong>Chewey Bot Official Server #announcements</strong><br>All text based commands are now inactive on Chewey Bot<br>To continue using commands you'll need to use them as slash commands"
+	}])
+})