feat: add parse function for extract repo name

src/octoget.ts

@@ -1,12 +1,13 @@
 import { mkdir, writeFile } from './fs';
 import { Client, getEntries } from './gh';
 import type { DownloadOption, DownloadResult } from './types';
+import { parseGitHubURI } from './utils';
 
 export async function download(
   path: string,
   options?: DownloadOption,
 ): Promise<DownloadResult> {
-  const source = extractSource(path);
+  const source = parseGitHubURI(path);
   const dir = resolveDir(options?.dir);
 
   const client = new Client();
@@ -31,13 +32,6 @@ export async function download(
   };
 }
 
-function extractSource(path: string): string {
-  // TODO extract repository source string from path
-  // `aster-mnch/octoget` -> `aster-mnch/octoget`
-  // `https://github.com/aster-mnch/octoget` -> `aster-mnch/octoget`
-  return path;
-}
-
 function resolveDir(dir: string | undefined): string {
   // TODO resolve path to download directory
   return dir ?? '.';

src/utils.ts

@@ -0,0 +1,9 @@
+export function parseGitHubURI(path: string): string {
+  const pattern =
+    /^(?<domain>https:\/\/github.com\/)?(?<repo>[\w.-]+\/[\w.-]+)(?<subdir>[^#]+)?(?<ref>#[\w.\/@-]+)?/;
+  const g = pattern.exec(path)?.groups;
+  if (g?.repo == null) {
+    throw new Error('Invalid format');
+  }
+  return g.repo;
+}

test/unit/utils.spec.ts

@@ -0,0 +1,16 @@
+import { describe, expect, it } from 'vitest';
+import { parseGitHubURI } from '../../src/utils';
+
+describe('parseGitHubURI', () => {
+  it('returns as is when given `org/repo` format', () => {
+    expect(parseGitHubURI('aster-mnch/octoget')).toBe('aster-mnch/octoget');
+  });
+
+  it('returns `org/repo` when given a full URI', () => {
+    expect(parseGitHubURI('https://github.com/aster-mnch/octoget')).toBe('aster-mnch/octoget');
+  });
+
+  it('throws "Invalid format" error when given invalid syntax', () => {
+    expect(() => parseGitHubURI('invalid')).toThrow('Invalid format');
+  });
+});