feat(misskey-js): acct.parseがURLを受け付けるように, acct.tsのテストを追加

packages/misskey-js/src/acct.ts

@@ -3,11 +3,50 @@ export type Acct = {
 	host: string | null;
 };
 
-export function parse(_acct: string): Acct {
-	let acct = _acct;
-	if (acct.startsWith('@')) acct = acct.substring(1);
-	const split = acct.split('@', 2);
-	return { username: split[0], host: split[1] || null };
+/**
+ * Parses a string and returns an Acct object.
+ * @param acct String to parse
+ *   The string should be in one of the following formats:
+ *   * At-mark style: `@username@example.com`
+ *   * Starts with `acct:`: `acct:username@example.com`
+ *   * URL style: `https://example.com/@username`, `https://self.example.com/@username@other.example.com`
+ * @param localHostname If provided and matches the host found in acct, the returned `host` will be set to `null`.
+ * @returns Acct object
+ */
+export function parse(acct: string, localHostname?: string): Acct {
+	//#region url style
+	if (acct.startsWith('https://') || acct.startsWith('http://')) {
+		const url = new URL(acct);
+		const path = url.pathname.split('/').find((p) => p.startsWith('@') && p.length >= 2);
+		if (!path) throw new Error('This url is not acct like.');
+
+		const split = path.split('@', 3); // ['', 'username', 'other.example.com']
+
+		let host: string | null = split[2] || url.hostname;
+		if (localHostname && host === localHostname) {
+			host = null;
+		}
+
+		return { username: split[1], host: host };
+	}
+	//#endregion
+
+	//#region at-mark and acct: style
+	let acctWithNoPrefix = acct;
+	if (acct.startsWith('@')) {
+		acctWithNoPrefix = acct.substring(1);
+	} else if (acct.startsWith('acct:')) {
+		acctWithNoPrefix = acct.substring(5);
+	}
+	const split = acctWithNoPrefix.split('@', 2);
+
+	let host: string | null = split[1] || null;
+	if (localHostname && host === localHostname) {
+		host = null;
+	}
+
+	return { username: split[0], host };
+	//#endregion
 }
 
 export function toString(acct: Acct): string {

packages/misskey-js/test/acct.ts

@@ -0,0 +1,75 @@
+import { describe, it, expect } from 'vitest';
+import * as acct from '../src/acct.js';
+
+describe('acct.parse', () => {
+	it('parses plain username', () => {
+		const res = acct.parse('alice');
+		expect(res).toEqual({ username: 'alice', host: null });
+	});
+
+	it('parses at-mark style without host', () => {
+		const res = acct.parse('@alice');
+		expect(res).toEqual({ username: 'alice', host: null });
+	});
+
+	it('parses at-mark style with host', () => {
+		const res = acct.parse('@alice@example.com');
+		expect(res).toEqual({ username: 'alice', host: 'example.com' });
+	});
+
+	it('nulls host for at-mark style when localHostname matches', () => {
+		const res = acct.parse('@alice@example.com', 'example.com');
+		expect(res).toEqual({ username: 'alice', host: null });
+	});
+
+	it('parses acct: style', () => {
+		const res = acct.parse('acct:alice@example.com');
+		expect(res).toEqual({ username: 'alice', host: 'example.com' });
+	});
+
+	it('nulls host for acct: style when localHostname matches', () => {
+		const res = acct.parse('acct:alice@example.com', 'example.com');
+		expect(res).toEqual({ username: 'alice', host: null });
+	});
+
+	it('parses url style https with same host -> host kept when localHostname not provided', () => {
+		const res = acct.parse('https://example.com/@alice');
+		expect(res).toEqual({ username: 'alice', host: 'example.com' });
+	});
+
+	it('parses url style http with same host and nulls host when localHostname matches', () => {
+		const res = acct.parse('http://example.com/@alice', 'example.com');
+		expect(res).toEqual({ username: 'alice', host: null });
+	});
+
+	it('parses url style with remote host contained in path', () => {
+		const res = acct.parse('https://self.example.com/@alice@other.example.com');
+		expect(res).toEqual({ username: 'alice', host: 'other.example.com' });
+	});
+
+	it('nulls host when localHostname matches the remote host in path', () => {
+		const res = acct.parse('https://self.example.com/@alice@other.example.com', 'other.example.com');
+		expect(res).toEqual({ username: 'alice', host: null });
+	});
+
+	it('throws on non-acct-like url path', () => {
+		expect(() => acct.parse('https://example.com/users/alice')).toThrowError();
+	});
+
+	it('parses correctly Mr.http', () => {
+		const res = acct.parse('http');
+		expect(res).toEqual({ username: 'http', host: null });
+	});
+});
+
+describe('acct.toString', () => {
+	it('returns username when host is null', () => {
+		expect(acct.toString({ username: 'alice', host: null })).toBe('alice');
+	});
+
+	it('returns username@host when host exists', () => {
+		expect(acct.toString({ username: 'alice', host: 'example.com' })).toBe('alice@example.com');
+	});
+});
+
+