fix: link peer deps should handle scope package path (#454)

closes cnpm/cnpm#408

lib/install_package.js

@@ -282,7 +282,10 @@ async function _install(parentDir, pkg, ancestors, options, context) {
         const key = `install:${peer.name}@${peer.version}`;
         const c = options.cache[key];
         if (c) {
-          const linkDir = path.join(realPkgDir, `../${c.package.name}`);
+          // scoped package
+          const relativePath = pkg.name && pkg.name.startsWith('@') ?
+            `../../${c.package.name}` : `../${c.package.name}`;
+          const linkDir = path.join(realPkgDir, relativePath);
           const relative = await utils.forceSymlink(c.dir, linkDir);
           debug('%s link peer package(%s@%s) %s => %s, parentDir: %s',
             displayName, c.package.name, c.package.version, linkDir, relative, realPkgDir);

test/fixtures/hotfix-emotion-react/index.js

@@ -0,0 +1,4 @@
+console.log(
+  require.resolve('@emotion/react'),
+  !!require('@emotion/react')
+);

test/fixtures/hotfix-emotion-react/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "hotfix-emotion-react",
+  "version": "1.0.0",
+  "scripts": {
+    "postinstall": "node index.js"
+  },
+  "dependencies": {
+    "@emotion/react": "latest",
+    "react": "latest"
+  }
+}

test/index.test.js

@@ -23,6 +23,16 @@ describe('test/index.test.js', () => {
     assert(await exists(path.join(root, 'node_modules/.store/@babel+preset-react@7.18.6/node_modules/@babel/plugin-transform-react-jsx')));
   });
 
+  it('should install @emotion/react with react, fix link pear deps bug', async () => {
+    const root = helper.fixtures('hotfix-emotion-react');
+    await rimraf(path.join(root, 'node_modules'));
+    await npminstall({
+      root,
+    });
+    assert(await isInstallDone(path.join(root, 'node_modules/@emotion/react')));
+    assert.equal(require(path.join(root, 'node_modules/@emotion/react/package.json')).name, '@emotion/react');
+  });
+
   it('should npminstall with options.pkgs', async () => {
     await npminstall({
       root: tmp,