Add new MFM animation syntax

src/mfm/language.ts

@@ -77,6 +77,7 @@ export const mfmLanguage = P.createLanguage({
 		r.jump,
 		r.flip,
 		r.twitch,
+		r.shake,
 		r.inlineCode,
 		r.mathInline,
 		r.mention,
@@ -124,6 +125,7 @@ export const mfmLanguage = P.createLanguage({
 	jump: r => P.regexp(/<jump>(.+?)<\/jump>/, 1).map(x => createTree('jump', r.inline.atLeast(1).tryParse(x), {})),
 	flip: r => P.regexp(/<flip>(.+?)<\/flip>/, 1).map(x => createTree('flip', r.inline.atLeast(1).tryParse(x), {})),
 	twitch: r => P.regexp(/<twitch>(.+?)<\/twitch>/, 1).map(x => createTree('twitch', r.inline.atLeast(1).tryParse(x), {})),
+	shake: r => P.regexp(/<shake>(.+?)<\/shake>/, 1).map(x => createTree('shake', r.inline.atLeast(1).tryParse(x), {})),
 	center: r => r.startOfLine.then(P.regexp(/<center>([\s\S]+?)<\/center>/, 1).map(x => createTree('center', r.inline.atLeast(1).tryParse(x), {}))),
 	inlineCode: () => P.regexp(/`([^´\n]+?)`/, 1).map(x => createLeaf('inlineCode', { code: x })),
 	mathBlock: r => r.startOfLine.then(P.regexp(/\\\[([\s\S]+?)\\\]/, 1).map(x => createLeaf('mathBlock', { formula: x.trim() }))),

src/mfm/to-html.ts

@@ -73,6 +73,12 @@ export function toHtml(tokens: MfmForest | null, mentionedRemoteUsers: IMentione
 			return el;
 		},
 
+		shake(token) {
+			const el = doc.createElement('i');
+			appendChildren(token.children, el);
+			return el;
+		},
+
 		flip(token) {
 			const el = doc.createElement('span');
 			appendChildren(token.children, el);

src/mfm/to-string.ts

@@ -52,6 +52,10 @@ export function toString(tokens: MfmForest | null, opts?: RestoreOptions): strin
 			return `<twitch>${appendChildren(token.children, opts)}</twitch>`;
 		},
 
+		shake(token, opts) {
+			return `<shake>${appendChildren(token.children, opts)}</shake>`;
+		},
+
 		flip(token, opts) {
 			return `<flip>${appendChildren(token.children, opts)}</flip>`;
 		},