Add a demo test

Author: Dimitar Markov

test/test-sftp.js

@@ -719,6 +719,23 @@ setup('WriteStream', mustCall((client, server) => {
   writer.end();
 }));
 
+setup('environment', { SSH2NODETEST: 'foo' }, mustCall((client, server) => {
+  const path_ = '/tmp/foo.txt';
+  const handle_ = Buffer.from('node.js');
+  const pflags_ = (OPEN_MODE.TRUNC | OPEN_MODE.CREAT | OPEN_MODE.WRITE);
+  server.on('OPEN', mustCall((id, path, pflags) => {
+    assert(id === 0, `Wrong request id: ${id}`);
+    assert(path === path_, `Wrong path: ${path}`);
+    assert(pflags === pflags_, `Wrong flags: ${flagsToHuman(pflags)}`);
+    server.handle(id, handle_);
+    server.end();
+  }));
+  client.open(path_, 'w', mustCall((err, handle) => {
+    assert(!err, `Unexpected open() error: ${err}`);
+    assert.deepStrictEqual(handle, handle_, 'handle mismatch');
+  }));
+}));
+
 {
   const { client, server } = setup_(
     'SFTP server aborts with exit-status',
@@ -757,7 +774,12 @@ setup('WriteStream', mustCall((client, server) => {
 
 
 // =============================================================================
-function setup(title, cb) {
+function setup(title, env, cb) {
+  if (typeof env === 'function') {
+    cb = env;
+    env = undefined;
+  }
+
   const { client, server } = setupSimple(DEBUG, title);
   let clientSFTP;
   let serverSFTP;
@@ -768,7 +790,7 @@ function setup(title, cb) {
   }, 2);
 
   client.on('ready', mustCall(() => {
-    client.sftp(mustCall((err, sftp) => {
+    client.sftp(env, mustCall((err, sftp) => {
       assert(!err, `[${title}] Unexpected client sftp start error: ${err}`);
       sftp.on('close', mustCall(() => {
         client.end();