Handle EPIPE on stdout gracefully

CHANGELOG.md

@@ -20,9 +20,17 @@ Please add one entry in this file for each change in Yarn's behavior. Use the sa
 
   [#7127](https://github.com/yarnpkg/yarn/pull/7127) - [**Eli Perelman**](https://github.com/eliperelman)
 
+- Prevents EPIPE errors from being printed.
+
+  [#7194](https://github.com/yarnpkg/yarn/pull/7194) - [**Abhishek Reddy**](https://github.com/arbscht)
+
 - Adds support for the npm enterprise URLs when computing the offline mirror filenames.
 
   [#7200](https://github.com/yarnpkg/yarn/pull/7200) - [**John Millikin**](https://john-millikin.com)
+
+- Tweaks the lockfile parser logic to parse a few extra cases
+
+  [#7210](https://github.com/yarnpkg/yarn/pull/7210) - [**Maël Nison**](https://twitter.com/arcanis)
 
 ## 1.15.2
 

__tests__/pipe.js

@@ -0,0 +1,96 @@
+/* @flow */
+/* eslint max-len: 0 */
+
+import execa from 'execa';
+import {sh} from 'puka';
+import makeTemp from './_temp.js';
+import * as fs from '../src/util/fs.js';
+
+const path = require('path');
+
+function runYarnStreaming(args: Array<string> = [], options: Object = {}): execa.ExecaChildPromise {
+  if (!options['env']) {
+    options['env'] = {...process.env};
+    options['extendEnv'] = false;
+  }
+  options['env']['FORCE_COLOR'] = 0;
+
+  return execa.shell(sh`${path.resolve(__dirname, '../bin/yarn')} ${args}`, options);
+}
+
+test('terminate console stream quietly on EPIPE', async () => {
+  const cwd = await makeTemp();
+  const packageJsonPath = path.join(cwd, 'package.json');
+  const initialManifestFile = JSON.stringify({name: 'test', license: 'ISC', version: '1.0.0'});
+
+  await fs.writeFile(packageJsonPath, initialManifestFile);
+
+  const {stdout, stderr} = runYarnStreaming(['versions'], {cwd});
+
+  stdout.destroy();
+
+  await new Promise((resolve, reject) => {
+    let stderrOutput = '';
+    stderr.on('readable', () => {
+      const chunk = stderr.read();
+      if (chunk) {
+        stderrOutput += chunk;
+      } else {
+        resolve(stderrOutput);
+      }
+    });
+    stderr.on('error', err => {
+      reject(err);
+    });
+  })
+    .then(stderrOutput => {
+      expect(stderrOutput).not.toMatch(/EPIPE/);
+    })
+    .catch(err => {
+      expect(err).toBeFalsy();
+    });
+});
+
+test('terminate console stream preserving zero exit code on EPIPE', async () => {
+  const cwd = await makeTemp();
+  const packageJsonPath = path.join(cwd, 'package.json');
+  const initialManifestFile = JSON.stringify({name: 'test', license: 'ISC', version: '1.0.0'});
+
+  await fs.writeFile(packageJsonPath, initialManifestFile);
+
+  const proc = runYarnStreaming(['versions'], {cwd});
+
+  const {stdout} = proc;
+
+  stdout.destroy();
+
+  await new Promise(resolve => {
+    proc.on('exit', function(code, signal) {
+      resolve(code);
+    });
+  }).then(exitCode => {
+    expect(exitCode).toEqual(0);
+  });
+});
+
+test('terminate console stream preserving non-zero exit code on EPIPE', async () => {
+  const cwd = await makeTemp();
+  const packageJsonPath = path.join(cwd, 'package.json');
+  const initialManifestFile = JSON.stringify({name: 'test', license: 'ISC', version: '1.0.0'});
+
+  await fs.writeFile(packageJsonPath, initialManifestFile);
+
+  const proc = runYarnStreaming(['add'], {cwd});
+
+  const {stdout} = proc;
+
+  stdout.destroy();
+
+  await new Promise(resolve => {
+    proc.on('exit', function(code, signal) {
+      resolve(code);
+    });
+  }).then(exitCode => {
+    expect(exitCode).toEqual(1);
+  });
+});

src/cli/index.js

@@ -26,6 +26,14 @@ import handleSignals from '../util/signal-handler.js';
 import {boolify, boolifyWithDefault} from '../util/conversion.js';
 import {ProcessTermError} from '../errors';
 
+process.stdout.prependListener('error', err => {
+  // swallow err only if downstream consumer process closed pipe early
+  if (err.code === 'EPIPE' || err.code === 'ERR_STREAM_DESTROYED') {
+    return;
+  }
+  throw err;
+});
+
 function findProjectRoot(base: string): string {
   let prev = null;
   let dir = base;