process: improve process.cwd() error message

src/node_process_methods.cc

@@ -163,9 +163,18 @@ static void Cwd(const FunctionCallbackInfo<Value>& args) {
   size_t cwd_len = sizeof(buf);
   int err = uv_cwd(buf, &cwd_len);
   if (err) {
-    return env->ThrowUVException(err, "uv_cwd");
+    std::string err_msg =
+        std::string("process.cwd failed with error ") + uv_strerror(err);
+    if (err == UV_ENOENT) {
+      // If err == UV_ENOENT it is necessary to notice the user
+      // that the current working dir was likely removed.
+      err_msg =
+          err_msg +
+          std::string(", the current working directory was likely removed ") +
+          std::string("without changing the working directory");
+    }
+    return env->ThrowUVException(err, "uv_cwd", err_msg.c_str());
   }
-
   Local<String> cwd;
   if (String::NewFromUtf8(env->isolate(), buf, NewStringType::kNormal, cwd_len)
           .ToLocal(&cwd)) {

test/known_issues/test-cwd-enoent-file.js

@@ -23,7 +23,7 @@ if (process.argv[2] === 'child') {
   process.chdir(dir);
   fs.rmdirSync(dir);
   assert.throws(process.cwd,
-                /^Error: ENOENT: no such file or directory, uv_cwd$/);
+                /^Error: ENOENT: process\.cwd failed with error no such file or directory, the current working directory was likely removed without changing the working directory, uv_cwd$/);
 
   const r = cp.spawnSync(process.execPath, [__filename, 'child']);
 

test/parallel/test-cwd-enoent-improved-message.js

@@ -0,0 +1,32 @@
+'use strict';
+
+const common = require('../common');
+const { isMainThread } = require('worker_threads');
+const assert = require('assert');
+const fs = require('fs');
+
+if (!isMainThread) {
+  common.skip('process.chdir is not available in Workers');
+}
+
+// Fails with EINVAL on SmartOS, EBUSY on Windows, EBUSY on AIX.
+if (common.isSunOS || common.isWindows || common.isAIX || common.isIBMi) {
+  common.skip('cannot rmdir current working directory');
+}
+
+const tmpdir = require('../common/tmpdir');
+const dirname = `${tmpdir.path}/cwd-does-not-exist-${process.pid}`;
+
+tmpdir.refresh();
+fs.mkdirSync(dirname);
+process.chdir(dirname);
+fs.rmdirSync(dirname);
+
+assert.throws(
+  () => process.cwd(),
+  {
+    code: 'ENOENT',
+    message: 'ENOENT: process.cwd failed with error no such file or directory,' +
+      ' the current working directory was likely removed without changing the working directory, uv_cwd',
+  }
+);