Skip setting hash if hash was not set previously

__tests__/commands/add.js

@@ -40,6 +40,10 @@ test.concurrent('install with arg', (): Promise<void> => {
   return runAdd({}, ['is-online'], 'install-with-arg');
 });
 
+test.concurrent('install from github', (): Promise<void> => {
+  return runAdd({}, ['substack/node-mkdirp#master'], 'install-github');
+});
+
 test.concurrent('install with --dev flag', (): Promise<void> => {
   return runAdd({dev: true}, ['left-pad@1.1.0'], 'add-with-flag', async (config) => {
     const lockfile = explodeLockfile(await fs.readFile(path.join(config.cwd, 'yarn.lock')));
@@ -571,5 +575,4 @@ test.concurrent('add should generate correct integrity file', (): Promise<void>
     }
     expect(allCorrect).toBe(true);
   });
-
 });

__tests__/commands/install.js

@@ -127,6 +127,10 @@ test.concurrent('install from git cache', (): Promise<void> => {
   });
 });
 
+test.concurrent('install from github', (): Promise<void> => {
+  return runInstall({}, 'install-github');
+});
+
 test.concurrent('install should dedupe dependencies avoiding conflicts 0', (): Promise<void> => {
   // A@2.0.1 -> B@2.0.0
   // B@1.0.0

__tests__/commands/ls.js

@@ -9,7 +9,6 @@ import Config from '../../src/config.js';
 
 jasmine.DEFAULT_TIMEOUT_INTERVAL = 90000;
 
-const stream = require('stream');
 const path = require('path');
 const os = require('os');
 
@@ -48,14 +47,7 @@ async function runLs(
     }
   }
 
-  let out = '';
-  const stdout = new stream.Writable({
-    decodeStrings: false,
-    write(data, encoding, cb) {
-      out += data;
-      cb();
-    },
-  });
+  const out = '';
 
   const reporter = new reporters.BufferReporter({stdout: null, stdin: null});
 

__tests__/commands/run.js

@@ -12,7 +12,6 @@ jasmine.DEFAULT_TIMEOUT_INTERVAL = 90000;
 
 const execCommand: $FlowFixMe = require('../../src/util/execute-lifecycle-script').execCommand;
 
-const stream = require('stream');
 const path = require('path');
 const os = require('os');
 
@@ -40,14 +39,7 @@ async function runRun(
     }
   }
 
-  let out = '';
-  const stdout = new stream.Writable({
-    decodeStrings: false,
-    write(data, encoding, cb) {
-      out += data;
-      cb();
-    },
-  });
+  const out = '';
 
   const reporter = new reporters.BufferReporter({stdout: null, stdin: null});
 

__tests__/fixtures/install/install-github/package.json

@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "mkdirp": "substack/node-mkdirp#master"
+  }
+}

end_to_end_tests/README.md

@@ -3,3 +3,4 @@ This directory contains end-to-end tests for Yarn. The tests perform the followi
 1. Spin up a fresh Docker container
 2. Install Yarn through the package repository
 3. Run `yarn add react` in a test directory
+4. Run `yarn add 'substack/node-mkdirp#master'` in a test directory

end_to_end_tests/data/run-yarn-test.sh

@@ -17,3 +17,4 @@ mkdir yarntest
 cd yarntest
 echo {} > package.json
 yarn add react || fail_with_log
+yarn add 'substack/node-mkdirp#master' || fail_with_log

src/cli/commands/install.js

@@ -26,12 +26,10 @@ import map from '../../util/map.js';
 import {sortAlpha} from '../../util/misc.js';
 
 const invariant = require('invariant');
-const userHome = require('user-home');
 const semver = require('semver');
 const emoji = require('node-emoji');
 const isCI = require('is-ci');
 const path = require('path');
-const fs2 = require('fs');
 
 const {version: YARN_VERSION, installationMethod: YARN_INSTALL_METHOD} = require('../../../package.json');
 const ONE_DAY = 1000 * 60 * 60 * 24;
@@ -97,7 +95,7 @@ function getUpdateCommand(): ?string {
   }
 
   if (YARN_INSTALL_METHOD === 'chocolatey') {
-      return 'choco upgrade yarn';
+    return 'choco upgrade yarn';
   }
 
   return null;

src/package-fetcher.js

@@ -88,7 +88,11 @@ export default class PackageFetcher {
         newPkg = res.package;
 
         // update with new remote
-        ref.remote.hash = res.hash;
+        // but only if there was a hash previously as the tarball fetcher does not provide a hash.
+        if (ref.remote.hash) {
+          ref.remote.hash = res.hash;
+        }
+
         if (res.resolved) {
           ref.remote.resolved = res.resolved;
         }