Revert "build,test: add duplicate symbol test"

This reverts commit 2761afbf73.

Building with `-fvisibility=hidden` breaks some of Node's add-on tests
and therefore likely also affects third-party add-ons. This change was
landed in a patch release so I'm opting to revert it until the next
major release.

PR-URL: https://github.com/nodejs/node-gyp/pull/1828
Refs: https://github.com/nodejs/node/pull/28647#issuecomment-511715968
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Rod Vagg <rod@vagg.org>

test/node_modules/duplicate_symbols/binding.cc

@@ -1,10 +0,0 @@
-#include <nan.h>
-#include "common.h"
-
-void Init(v8::Local<v8::Object> exports) {
-  Nan::Set(exports, Nan::New("pointerCheck").ToLocalChecked(),
-    Nan::GetFunction(
-      Nan::New<v8::FunctionTemplate>(Something::PointerCheck)).ToLocalChecked());
-}
-
-NODE_MODULE(NODE_GYP_MODULE_NAME, Init)

test/node_modules/duplicate_symbols/binding.gyp

@@ -1,19 +0,0 @@
-{
-  "target_defaults": {
-    "include_dirs": [
-      "<!(node -e \"require('nan')\")"
-    ],
-    "sources": [
-      "binding.cc",
-      "extra.cc"
-    ]
-  },
-  "targets": [
-    {
-      "target_name": "binding1",
-    },
-    {
-      "target_name": "binding2",
-    }
-  ]
-}

test/node_modules/duplicate_symbols/common.h

@@ -1,37 +0,0 @@
-#ifndef DUPLICATE_SYMBOLS_COMMON_H_
-#define DUPLICATE_SYMBOLS_COMMON_H_
-
-#include <nan.h>
-
-class Something {
- public:
-  static void PointerCheck(const Nan::FunctionCallbackInfo<v8::Value>& info);
-};
-
-// Removing the inline keyword below will result in the addon failing to link
-// on OSX because of a duplicate symbol.
-inline void
-Something::PointerCheck(const Nan::FunctionCallbackInfo<v8::Value>& info) {
-  v8::Local<v8::Value> v8result;
-
-  if (info.Length() > 0) {
-    // If an argument was passed in, it is a pointer to the `PointerCheck`
-    // method from the other addon. So, we compare it to the value of the
-    // pointer to the `PointerCheck` method in this addon, and return
-    // `"equal"` if they are equal, and `"not equal"` otherwise".
-
-    const char* result =
-      (reinterpret_cast<void*>(Something::PointerCheck) ==
-          info[0].As<v8::External>()->Value()) ?
-              "equal" : "not equal";
-    v8result = Nan::New(result).ToLocalChecked();
-  } else {
-    // If no argument was passed in, we wrap the pointer to the `PointerCheck`
-    // method in this addon into a `v8::External` and pass it into JavaScript.
-    v8result = Nan::New<v8::External>(
-        reinterpret_cast<void*>(Something::PointerCheck));
-  }
-  info.GetReturnValue().Set(v8result);
-}
-
-#endif  // DUPLICATE_SYMBOLS_COMMON_H_

test/node_modules/duplicate_symbols/extra.cc

@@ -1,6 +0,0 @@
-#include "common.h"
-
-// It is important that common.h be included from two different translation
-// units, because doing so can create duplicate symbols in some instances. If
-// it does so and fails to build because of it, that is considered a test
-// failure.

test/node_modules/duplicate_symbols/index.js

@@ -1,5 +0,0 @@
-'use strict'
-module.exports = {
-  pointerCheck1: require('bindings')('binding1').pointerCheck,
-  pointerCheck2: require('bindings')('binding2').pointerCheck
-};

test/node_modules/duplicate_symbols/package.json

@@ -1,14 +0,0 @@
-{
-  "name": "duplicate_symbols",
-  "version": "0.0.0",
-  "description": "Duplicate Symbols Test",
-  "main": "index.js",
-  "private": true,
-  "dependencies": {
-    "bindings": "~1.2.1",
-    "nan": "^2.14.0"
-  },
-  "scripts": {
-    "test": "node index.js"
-  }
-}

test/test-addon.js

@@ -18,15 +18,6 @@ function runHello (hostProcess) {
   return execFileSync(hostProcess, [ '-e', testCode ], { cwd: __dirname }).toString()
 }
 
-function runDuplicateBindings () {
-  const hostProcess = process.execPath
-  var testCode =
-    'console.log((function(bindings) {' +
-    'return bindings.pointerCheck1(bindings.pointerCheck2());' +
-    "})(require('duplicate_symbols')))"
-  return execFileSync(hostProcess, [ '-e', testCode ], { cwd: __dirname }).toString()
-}
-
 function getEncoding () {
   var code = 'import locale;print(locale.getdefaultlocale()[1])'
   return execFileSync('python', [ '-c', code ]).toString().trim()
@@ -60,21 +51,6 @@ test('build simple addon', function (t) {
   proc.stderr.setEncoding('utf-8')
 })
 
-test('make sure addon symbols do not overlap', function (t) {
-  t.plan(3)
-
-  var addonPath = path.resolve(__dirname, 'node_modules', 'duplicate_symbols')
-  // Set the loglevel otherwise the output disappears when run via 'npm test'
-  var cmd = [nodeGyp, 'rebuild', '-C', addonPath, '--loglevel=verbose']
-  execFile(process.execPath, cmd, function (err, stdout, stderr) {
-    var logLines = stderr.trim().split(/\r?\n/)
-    var lastLine = logLines[logLines.length - 1]
-    t.strictEqual(err, null)
-    t.strictEqual(lastLine, 'gyp info ok', 'should end in ok')
-    t.strictEqual(runDuplicateBindings().trim(), 'not equal')
-  })
-})
-
 test('build simple addon in path with non-ascii characters', function (t) {
   t.plan(1)