Fix textual message stripping new line (#7239)

src/HtmlUtils.tsx

@@ -411,8 +411,9 @@ export interface IOptsReturnString extends IOpts {
 export function bodyToHtml(content: IContent, highlights: string[], opts: IOptsReturnString): string;
 export function bodyToHtml(content: IContent, highlights: string[], opts: IOptsReturnNode): ReactNode;
 export function bodyToHtml(content: IContent, highlights: string[], opts: IOpts = {}) {
-    const isHtmlMessage = content.format === "org.matrix.custom.html" && content.formatted_body;
+    const isFormattedBody = content.format === "org.matrix.custom.html" && content.formatted_body;
     let bodyHasEmoji = false;
+    let isHtmlMessage = false;
 
     let sanitizeParams = sanitizeHtmlParams;
     if (opts.forComposerQuote) {
@@ -449,20 +450,23 @@ export function bodyToHtml(content: IContent, highlights: string[], opts: IOpts
         if (opts.stripReplyFallback && formattedBody) formattedBody = ReplyChain.stripHTMLReply(formattedBody);
         strippedBody = opts.stripReplyFallback ? ReplyChain.stripPlainReply(plainBody) : plainBody;
 
-        bodyHasEmoji = mightContainEmoji(isHtmlMessage ? formattedBody : plainBody);
+        bodyHasEmoji = mightContainEmoji(isFormattedBody ? formattedBody : plainBody);
 
         // Only generate safeBody if the message was sent as org.matrix.custom.html
-        if (isHtmlMessage) {
+        if (isFormattedBody) {
             isDisplayedWithHtml = true;
-            safeBody = sanitizeHtml(formattedBody, sanitizeParams);
 
-            if (SettingsStore.getValue("feature_latex_maths")) {
+            safeBody = sanitizeHtml(formattedBody, sanitizeParams);
-                const phtml = cheerio.load(safeBody, {
+            const phtml = cheerio.load(safeBody, {
-                    // @ts-ignore: The `_useHtmlParser2` internal option is the
+                // @ts-ignore: The `_useHtmlParser2` internal option is the
-                    // simplest way to both parse and render using `htmlparser2`.
+                // simplest way to both parse and render using `htmlparser2`.
-                    _useHtmlParser2: true,
+                _useHtmlParser2: true,
-                    decodeEntities: false,
+                decodeEntities: false,
-                });
+            });
+            const isPlainText = phtml.html() === phtml.root().text();
+            isHtmlMessage = isFormattedBody && !isPlainText;
+
+            if (isHtmlMessage && SettingsStore.getValue("feature_latex_maths")) {
                 // @ts-ignore - The types for `replaceWith` wrongly expect
                 // Cheerio instance to be returned.
                 phtml('div, span[data-mx-maths!=""]').replaceWith(function(i, e) {

test/components/views/messages/TextualBody-test.js

@@ -282,6 +282,30 @@ describe("<TextualBody />", () => {
                 '!ZxbRYPQXDXKGmDnJNg:example.com</a></span> with vias</span>',
             );
         });
+
+        it('renders formatted body without html corretly', () => {
+            const ev = mkEvent({
+                type: "m.room.message",
+                room: "room_id",
+                user: "sender",
+                content: {
+                    body: "escaped \\*markdown\\*",
+                    msgtype: "m.text",
+                    format: "org.matrix.custom.html",
+                    formatted_body: "escaped *markdown*",
+                },
+                event: true,
+            });
+
+            const wrapper = mount(<TextualBody mxEvent={ev} />);
+
+            const content = wrapper.find(".mx_EventTile_body");
+            expect(content.html()).toBe(
+                '<span class="mx_EventTile_body" dir="auto">' +
+                'escaped *markdown*' +
+                '</span>',
+            );
+        });
     });
 
     it("renders url previews correctly", () => {