test,util: add missing tests and conditions

1) Add missing unit tests by `ucs-2` in different kinds of cases.
2) Add missing unit tests by `usc-2` in different kinds of cases.
3) Fix a bug：We cannot find `ucs-2` in `case 5`'s `if` condition after
`toLowerCase()`

PR-URL: https://github.com/nodejs/node/pull/21455
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

3 files changed, 26 insertions, 9 deletions

diff --git a/benchmark/util/normalize-encoding.js b/benchmark/util/normalize-encoding.js
index 96eab1912d..65cf5b1b0c 100644
--- a/benchmark/util/normalize-encoding.js
+++ b/benchmark/util/normalize-encoding.js
@@ -4,18 +4,25 @@ const common = require('../common.js');
 const assert = require('assert');
 
 const groupedInputs = {
-  group_common: ['undefined', 'utf8', 'utf-8', 'base64', 'binary', 'latin1'],
-  group_upper: ['UTF-8', 'UTF8', 'UCS2', 'UTF-16LE', 'UTF16LE', 'BASE64'],
-  group_uncommon: [ 'foo', '1', 'false', 'undefined', '[]'],
+  group_common: ['undefined', 'utf8', 'utf-8', 'base64',
+                 'binary', 'latin1', 'ucs-2', 'usc-2'],
+  group_upper: ['UTF-8', 'UTF8', 'UCS2', 'UTF-16LE',
+                'UTF16LE', 'BASE64', 'UCS-2', 'USC-2'],
+  group_uncommon: ['foo', '1', 'false', 'undefined', '[]', '{}'],
   group_misc: ['', 'utf16le', 'usc2', 'hex', 'HEX', 'BINARY']
 };
 
 const inputs = [
-  '', 'utf8', 'utf-8', 'UTF-8',
-  'UTF8', 'Utf8', 'uTf-8', 'utF-8', 'ucs2',
-  'UCS2', 'utf16le', 'utf-16le', 'UTF-16LE', 'UTF16LE',
+  '',
+  'utf8', 'utf-8', 'UTF-8',
+  'UTF8', 'Utf8', 'uTf-8', 'utF-8',
+  'ucs2', 'UCS2', 'UcS2',
+  'USC2', 'usc2', 'uSc2',
+  'ucs-2', 'UCS-2', 'UcS-2',
+  'usc-2', 'USC-2', 'uSc-2',
+  'utf16le', 'utf-16le', 'UTF-16LE', 'UTF16LE',
   'binary', 'BINARY', 'latin1', 'base64', 'BASE64',
-  'hex', 'HEX', 'foo', '1', 'false', 'undefined', '[]'];
+  'hex', 'HEX', 'foo', '1', 'false', 'undefined', '[]', '{}'];
 
 const bench = common.createBenchmark(main, {
   input: inputs.concat(Object.keys(groupedInputs)),
@@ -42,6 +49,8 @@ function getInput(input) {
       return [undefined];
     case '[]':
       return [[]];
+    case '{}':
+      return [{}];
     default:
       return [input];
   }
@@ -53,7 +62,7 @@ function main({ input, n }) {
   var noDead = '';
 
   bench.start();
-  for (var i = 0; i < n; i += 1) {
+  for (var i = 0; i < n; ++i) {
     for (var j = 0; j < inputs.length; ++j) {
       noDead = normalizeEncoding(inputs[j]);
     }
diff --git a/lib/internal/util.js b/lib/internal/util.js
index 07515e2e09..bc513e7fed 100644
--- a/lib/internal/util.js
+++ b/lib/internal/util.js
@@ -115,7 +115,7 @@ function slowCases(enc) {
       if (enc === 'ucs2' || enc === 'UCS2') return 'utf16le';
       enc = `${enc}`.toLowerCase();
       if (enc === 'utf8') return 'utf8';
-      if (enc === 'ucs2' || enc === 'UCS2') return 'utf16le';
+      if (enc === 'ucs2') return 'utf16le';
       break;
     case 3:
       if (enc === 'hex' || enc === 'HEX' || `${enc}`.toLowerCase() === 'hex')
@@ -131,6 +131,7 @@ function slowCases(enc) {
       if (enc === 'utf-8') return 'utf8';
       if (enc === 'ascii') return 'ascii';
       if (enc === 'usc-2') return 'utf16le';
+      if (enc === 'ucs-2') return 'utf16le';
       break;
     case 6:
       if (enc === 'base64') return 'base64';
diff --git a/test/parallel/test-internal-util-normalizeencoding.js b/test/parallel/test-internal-util-normalizeencoding.js
index 081255cef0..2f16d55fad 100644
--- a/test/parallel/test-internal-util-normalizeencoding.js
+++ b/test/parallel/test-internal-util-normalizeencoding.js
@@ -18,10 +18,16 @@ const tests = [
   ['utF-8', 'utf8'],
   ['ucs2', 'utf16le'],
   ['UCS2', 'utf16le'],
+  ['ucs-2', 'utf16le'],
+  ['UCS-2', 'utf16le'],
+  ['UcS-2', 'utf16le'],
   ['utf16le', 'utf16le'],
   ['utf-16le', 'utf16le'],
   ['UTF-16LE', 'utf16le'],
   ['UTF16LE', 'utf16le'],
+  ['usc-2', 'utf16le'],
+  ['USC-2', 'utf16le'],
+  ['uSc-2', 'utf16le'],
   ['binary', 'latin1'],
   ['BINARY', 'latin1'],
   ['latin1', 'latin1'],
@@ -36,6 +42,7 @@ const tests = [
   [NaN, undefined],
   [0, undefined],
   [[], undefined],
+  [{}, undefined]
 ];
 
 tests.forEach((e, i) => {