fix: handle parallel installs (#84)

* fix: handle parallel installs

* build: skip unnecessary shims

.github/workflows/ci.yml

@@ -32,6 +32,9 @@ jobs:
         env:
           TARGET_BRANCH: ${{github.event.pull_request.base.ref}}
 
+      - name: 'Check for type errors'
+        run: yarn typecheck
+
   build:
     strategy:
       fail-fast: false

mkshims.ts

@@ -5,9 +5,14 @@ import path                         from 'path';
 import {Engine}                     from './sources/Engine';
 import {SupportedPackageManagerSet} from './sources/types';
 
-const EXCLUDE_SHIMS = new Set([
-  `vcc.js`,
-]);
+function shouldGenerateShim(name: string) {
+  if (name === 'vcc.js') {
+    return false;
+  } else if (name.startsWith('vendors')) {
+    return false;
+  }
+  return true;
+}
 
 const engine = new Engine();
 
@@ -38,7 +43,7 @@ async function main() {
   }
 
   for (const binaryName of fs.readdirSync(distDir)) {
-    if (EXCLUDE_SHIMS.has(binaryName))
+    if (shouldGenerateShim(binaryName) === false)
       continue;
 
     await cmdShim(path.join(distDir, binaryName), path.join(shimsDir, path.basename(binaryName, `.js`)), {createCmdFile: true});
@@ -55,12 +60,16 @@ async function main() {
   const remapPath = (p: string) => path.resolve(__dirname, path.relative(virtualNodewinDir, p));
 
   const easyStatFs = Object.assign(Object.create(fs), {
-    readFile: (p: string, encoding: string, cb: (err: any, str: string) => void) => fs.readFile(remapPath(p), encoding, cb),
+    readFile: (p: string, encoding: BufferEncoding, cb: (err: any, str: string) => void) => fs.readFile(remapPath(p), encoding, cb),
     stat: (p: string, cb: () => void) => fs.stat(remapPath(p), cb),
   });
 
-  for (const binaryName of fs.readdirSync(distDir))
+  for (const binaryName of fs.readdirSync(distDir)) {
+    if (shouldGenerateShim(binaryName) === false)
+      continue;
+
     await cmdShim(path.join(virtualNodewinDir, `dist/${binaryName}`), path.join(physicalNodewinDir, path.basename(binaryName, `.js`)), {createCmdFile: true, fs: easyStatFs});
+  }
 
   console.log(`All shims have been generated.`);
 }

package.json

@@ -27,7 +27,8 @@
     "@babel/preset-typescript": "^7.13.0",
     "@types/debug": "^4.1.5",
     "@types/jest": "^26.0.23",
-    "@types/node": "^13.9.2",
+    "@types/node": "^17.0.10",
+    "@types/rimraf": "^3.0.2",
     "@types/semver": "^7.1.0",
     "@types/tar": "^4.0.3",
     "@types/which": "^1.3.2",
@@ -43,6 +44,7 @@
     "eslint-plugin-arca": "^0.9.5",
     "jest": "^26.0.0",
     "nock": "^13.0.4",
+    "rimraf": "^3.0.2",
     "semver": "^7.1.3",
     "supports-color": "^7.1.0",
     "tar": "^6.0.1",
@@ -56,10 +58,11 @@
     "which": "^2.0.2"
   },
   "scripts": {
-    "build": "rm -rf dist && webpack && ts-node ./mkshims.ts",
+    "build": "rm -rf dist shims && webpack && ts-node ./mkshims.ts",
     "corepack": "ts-node ./sources/main.ts",
     "prepack": "node ./.yarn/releases/*.*js build",
     "postpack": "rm -rf dist shims",
+    "typecheck": "tsc --noEmit",
     "test": "yarn jest"
   },
   "files": [

sources/corepackUtils.ts

@@ -87,39 +87,50 @@ export async function installVersion(installTarget: string, locator: Locator, {s
   const url = spec.url.replace(`{}`, locator.reference);
   debugUtils.log(`Installing ${locator.name}@${locator.reference} from ${url}`);
 
-  return await fsUtils.mutex(installFolder, async () => {
-    // Creating a temporary folder inside the install folder means that we
-    // are sure it'll be in the same drive as the destination, so we can
-    // just move it there atomically once we are done
+  // Creating a temporary folder inside the install folder means that we
+  // are sure it'll be in the same drive as the destination, so we can
+  // just move it there atomically once we are done
 
-    const tmpFolder = folderUtils.getTemporaryFolder(installTarget);
-    const stream = await httpUtils.fetchUrlStream(url);
+  const tmpFolder = folderUtils.getTemporaryFolder(installTarget);
+  const stream = await httpUtils.fetchUrlStream(url);
 
-    const parsedUrl = new URL(url);
-    const ext = path.posix.extname(parsedUrl.pathname);
+  const parsedUrl = new URL(url);
+  const ext = path.posix.extname(parsedUrl.pathname);
 
-    let outputFile: string | null = null;
+  let outputFile: string | null = null;
 
-    let sendTo: any;
-    if (ext === `.tgz`) {
-      sendTo = tar.x({strip: 1, cwd: tmpFolder});
-    } else if (ext === `.js`) {
-      outputFile = path.join(tmpFolder, path.posix.basename(parsedUrl.pathname));
-      sendTo = fs.createWriteStream(outputFile);
-    }
+  let sendTo: any;
+  if (ext === `.tgz`) {
+    sendTo = tar.x({strip: 1, cwd: tmpFolder});
+  } else if (ext === `.js`) {
+    outputFile = path.join(tmpFolder, path.posix.basename(parsedUrl.pathname));
+    sendTo = fs.createWriteStream(outputFile);
+  }
 
-    stream.pipe(sendTo);
+  stream.pipe(sendTo);
 
-    await new Promise(resolve => {
-      sendTo.on(`finish`, resolve);
-    });
+  await new Promise(resolve => {
+    sendTo.on(`finish`, resolve);
+  });
 
-    await fs.promises.mkdir(path.dirname(installFolder), {recursive: true});
+  await fs.promises.mkdir(path.dirname(installFolder), {recursive: true});
+  try {
     await fs.promises.rename(tmpFolder, installFolder);
+  } catch (err) {
+    if (
+      err.code === `ENOTEMPTY` ||
+      // On Windows the error code is EPERM so we check if it is a directory
+      (err.code === `EPERM` && (await fs.promises.stat(installFolder)).isDirectory())
+    ) {
+      debugUtils.log(`Another instance of corepack installed ${locator.name}@${locator.reference}`);
+      await fsUtils.rimraf(tmpFolder);
+    } else {
+      throw err;
+    }
+  }
 
-    debugUtils.log(`Install finished`);
-    return installFolder;
-  });
+  debugUtils.log(`Install finished`);
+  return installFolder;
 }
 
 export async function runVersion(installSpec: { location: string, spec: PackageManagerSpec }, locator: Locator, binName: string, args: Array<string>, context: Context) {

sources/fsUtils.ts

@@ -1,3 +1,24 @@
-export async function mutex<T>(p: string, cb: () => Promise<T>) {
-  return await cb();
+import fs from 'fs';
+
+export async function rimraf(path: string) {
+  const [major, minor] = process.versions.node.split(`.`).map(section => Number(section));
+
+  if (major > 14 || (major === 14 && minor >= 14)) {
+    // rm was added in v14.14.0
+    return fs.promises.rm(path, {recursive: true});
+  } else if (major > 12 || (major === 12 && minor >= 10)) {
+    // rmdir got support for recursive in v12.10.0 and was deprecated in v14.14.0
+    return fs.promises.rmdir(path, {recursive: true});
+  } else {
+    const rimraf = await import(`rimraf`);
+    return new Promise<void>((resolve, reject) => {
+      rimraf.default(path, err => {
+        if (err) {
+          reject(err);
+        } else {
+          resolve();
+        }
+      });
+    });
+  }
 }

tests/main.test.ts

@@ -328,3 +328,30 @@ it(`should support running package managers with bin array`, async () => {
     });
   });
 });
+
+it(`should handle parallel installs`, async () => {
+  await xfs.mktempPromise(async cwd => {
+    await xfs.writeJsonPromise(ppath.join(cwd, `package.json` as Filename), {
+      packageManager: `yarn@2.2.2`,
+    });
+
+    await expect(Promise.all([
+      runCli(cwd, [`yarn`, `--version`]),
+      runCli(cwd, [`yarn`, `--version`]),
+      runCli(cwd, [`yarn`, `--version`]),
+    ])).resolves.toMatchObject([
+      {
+        stdout: `2.2.2\n`,
+        exitCode: 0,
+      },
+      {
+        stdout: `2.2.2\n`,
+        exitCode: 0,
+      },
+      {
+        stdout: `2.2.2\n`,
+        exitCode: 0,
+      },
+    ]);
+  });
+});

tsconfig.json

@@ -10,6 +10,7 @@
     "lib": ["dom", "es2017", "esnext.asynciterable"],
     "module": "commonjs",
     "resolveJsonModule": true,
+    "skipLibCheck": true,
     "target": "es2017"
   }
 }