Fix username/mention regexes

* Allow underscore instead of hypen
* Fix domain part handling
* Add tests for remote mention

src/client/app/common/views/components/signup.vue

@@ -76,7 +76,7 @@ export default Vue.extend({
 			}
 
 			const err =
-				!this.username.match(/^[a-zA-Z0-9\-]+$/) ? 'invalid-format' :
+				!this.username.match(/^[a-zA-Z0-9_]+$/) ? 'invalid-format' :
 				this.username.length < 3 ? 'min-range' :
 				this.username.length > 20 ? 'max-range' :
 				null;

src/client/app/dev/views/new-app.vue

@@ -65,7 +65,7 @@ export default Vue.extend({
 			}
 
 			const err =
-				!this.nid.match(/^[a-zA-Z0-9\-]+$/) ? 'invalid-format' :
+				!this.nid.match(/^[a-zA-Z0-9_]+$/) ? 'invalid-format' :
 				this.nid.length < 3                 ? 'min-range' :
 				this.nid.length > 30                ? 'max-range' :
 				null;

src/models/app.ts

@@ -24,7 +24,7 @@ export type IApp = {
 };
 
 export function isValidNameId(nameId: string): boolean {
-	return typeof nameId == 'string' && /^[a-zA-Z0-9\-]{3,30}$/.test(nameId);
+	return typeof nameId == 'string' && /^[a-zA-Z0-9_]{3,30}$/.test(nameId);
 }
 
 /**

src/models/user.ts

@@ -89,7 +89,7 @@ export const isRemoteUser = (user: any): user is IRemoteUser =>
 
 //#region Validators
 export function validateUsername(username: string): boolean {
-	return typeof username == 'string' && /^[a-zA-Z0-9\-]{3,20}$/.test(username);
+	return typeof username == 'string' && /^[a-zA-Z0-9_]{3,20}$/.test(username);
 }
 
 export function validatePassword(password: string): boolean {

src/text/parse/elements/mention.ts

@@ -4,7 +4,7 @@
 import parseAcct from '../../../acct/parse';
 
 module.exports = text => {
-	const match = text.match(/^(?:@[a-zA-Z0-9\-]+){1,2}/);
+	const match = text.match(/^@[a-z0-9_]+(?:@[a-z0-9\.\-]+[a-z0-9])?/i);
 	if (!match) return null;
 	const mention = match[0];
 	const { username, host } = parseAcct(mention.substr(1));