test: fix losing original env vars issue

Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
PR-URL: #3190

Author: Junliang Yan

test/parallel/test-child-process-spawnsync-env.js

@@ -8,7 +8,7 @@ if (process.argv[2] === 'child') {
 } else {
   var expected = 'bar';
   var child = cp.spawnSync(process.execPath, [__filename, 'child'], {
-    env: {foo: expected}
+    env: Object.assign(process.env, { foo: expected })
   });
 
   assert.equal(child.stdout.toString().trim(), expected);

test/parallel/test-fs-readfile-error.js

@@ -16,7 +16,7 @@ var callbacks = 0;
 function test(env, cb) {
   var filename = path.join(common.fixturesDir, 'test-fs-readfile-error.js');
   var execPath = '"' + process.execPath + '" "' + filename + '"';
-  var options = { env: env || {} };
+  var options = { env: Object.assign(process.env, env) };
   exec(execPath, options, function(err, stdout, stderr) {
     assert(err);
     assert.equal(stdout, '');

test/sequential/test-net-GH-5504.js

@@ -53,12 +53,6 @@ function parent() {
   var serverExited = false;
   var clientExited = false;
   var serverListened = false;
-  var opt = {
-    env: {
-      NODE_DEBUG: 'net',
-      NODE_COMMON_PORT: process.env.NODE_COMMON_PORT,
-    }
-  };
 
   process.on('exit', function() {
     assert(serverExited);
@@ -75,7 +69,11 @@ function parent() {
     });
   }, common.platformTimeout(2000)).unref();
 
-  var s = spawn(node, [__filename, 'server'], opt);
+  var s = spawn(node, [__filename, 'server'], {
+    env: Object.assign(process.env, {
+      NODE_DEBUG: 'net'
+    })
+  });
   var c;
 
   wrap(s.stderr, process.stderr, 'SERVER 2>');

test/sequential/test-stdin-script-child.js

@@ -4,9 +4,9 @@ var assert = require('assert');
 
 var spawn = require('child_process').spawn;
 var child = spawn(process.execPath, [], {
-  env: {
+  env: Object.assign(process.env, {
     NODE_DEBUG: process.argv[2]
-  }
+  })
 });
 var wanted = child.pid + '\n';
 var found = '';

test/sequential/test-util-debug.js

@@ -27,12 +27,7 @@ function test(environ, shouldWrite) {
 
   var spawn = require('child_process').spawn;
   var child = spawn(process.execPath, [__filename, 'child'], {
-    // Lttng requires the HOME env variable or it prints to stderr,
-    // This is not really ideal, as it breaks this test, so the HOME
-    // env variable is passed to the child to make the test pass.
-    // this is fixed in the next version of lttng (2.7+), so we can
-    // remove it at sometime in the future.
-    env: { NODE_DEBUG: environ, HOME: process.env.HOME }
+    env: Object.assign(process.env, { NODE_DEBUG: environ })
   });
 
   expectErr = expectErr.split('%PID%').join(child.pid);