util: implement util.getSystemErrorName()

Reimplement uv.errname() as internal/util.getSystemErrorName() to
avoid the memory leaks caused by unknown error codes
and avoid calling into C++ for the error names. Also
expose it as a public API for external use.

PR-URL: https://github.com/nodejs/node/pull/18186
Refs: http://docs.libuv.org/en/v1.x/errors.html#c.uv_err_name
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

1 files changed, 34 insertions, 25 deletions

diff --git a/test/parallel/test-uv-errno.js b/test/parallel/test-uv-errno.js
index e4a40f20c8..8b10b52c00 100644
--- a/test/parallel/test-uv-errno.js
+++ b/test/parallel/test-uv-errno.js
@@ -2,9 +2,12 @@
 
 const common = require('../common');
 const assert = require('assert');
-const util = require('util');
-const uv = process.binding('uv');
+const {
+  getSystemErrorName,
+  _errnoException
+} = require('util');
 
+const uv = process.binding('uv');
 const keys = Object.keys(uv);
 
 keys.forEach((key) => {
@@ -12,33 +15,39 @@ keys.forEach((key) => {
     return;
 
   assert.doesNotThrow(() => {
-    const err = util._errnoException(uv[key], 'test');
+    const err = _errnoException(uv[key], 'test');
     const name = uv.errname(uv[key]);
-    assert.strictEqual(err.code, err.errno);
+    assert.strictEqual(getSystemErrorName(uv[key]), name);
     assert.strictEqual(err.code, name);
+    assert.strictEqual(err.code, err.errno);
     assert.strictEqual(err.message, `test ${name}`);
   });
 });
 
-['test', {}, []].forEach((key) => {
-  common.expectsError(
-    () => util._errnoException(key),
-    {
-      code: 'ERR_INVALID_ARG_TYPE',
-      type: TypeError,
-      message: 'The "err" argument must be of type number. ' +
-               `Received type ${typeof key}`
-    });
-});
+function runTest(fn) {
+  ['test', {}, []].forEach((err) => {
+    common.expectsError(
+      () => fn(err),
+      {
+        code: 'ERR_INVALID_ARG_TYPE',
+        type: TypeError,
+        message: 'The "err" argument must be of type number. ' +
+                 `Received type ${typeof err}`
+      });
+  });
 
-[0, 1, Infinity, -Infinity, NaN].forEach((key) => {
-  common.expectsError(
-    () => util._errnoException(key),
-    {
-      code: 'ERR_OUT_OF_RANGE',
-      type: RangeError,
-      message: 'The value of "err" is out of range. ' +
-               'It must be a negative integer. ' +
-               `Received ${key}`
-    });
-});
+  [0, 1, Infinity, -Infinity, NaN].forEach((err) => {
+    common.expectsError(
+      () => fn(err),
+      {
+        code: 'ERR_OUT_OF_RANGE',
+        type: RangeError,
+        message: 'The value of "err" is out of range. ' +
+                 'It must be a negative integer. ' +
+                 `Received ${err}`
+      });
+  });
+}
+
+runTest(_errnoException);
+runTest(getSystemErrorName);