[Fix] preserveSymlinks: false ensure that files are realpathed

.eslintrc

@@ -27,5 +27,13 @@
         "object-curly-newline": 0,
         "operator-linebreak": [2, "before"],
         "sort-keys": 0,
-    }
+    },
+    "overrides": [
+        {
+            "files": "test/resolver/nested_symlinks/mylib/*.js",
+            "rules": {
+                "no-throw-literal": 0,
+            },
+        },
+    ],
 }

appveyor.yml

@@ -32,6 +32,9 @@ platform:
 
 # Install scripts. (runs after repo cloning)
 install:
+ # Fix symlinks in working copy (see https://github.com/appveyor/ci/issues/650#issuecomment-186592582) / https://github.com/charleskorn/batect/commit/d08986802ec43086902958c4ee7e57ff3e71dbef
+ - git config core.symlinks true
+ - git reset --hard
  # Get the latest stable version of Node.js or io.js
  - ps: Install-Product node $env:nodejs_version $env:platform
  - IF %nodejs_version% EQU 0.6 npm config set strict-ssl false && npm -g install [email protected]

lib/async.js

@@ -99,8 +99,15 @@ module.exports = function resolve(x, options, callback) {
         } else loadNodeModules(x, basedir, function (err, n, pkg) {
             if (err) cb(err);
             else if (core[x]) return cb(null, x);
-            else if (n) return cb(null, n, pkg);
-            else {
+            else if (n) {
+                return maybeUnwrapSymlink(n, opts, function (err, realN) {
+                    if (err) {
+                        cb(err);
+                    } else {
+                        cb(null, realN, pkg);
+                    }
+                });
+            } else {
                 var moduleError = new Error("Cannot find module '" + x + "' from '" + parent + "'");
                 moduleError.code = 'MODULE_NOT_FOUND';
                 cb(moduleError);
@@ -113,8 +120,15 @@ module.exports = function resolve(x, options, callback) {
         else if (m) cb(null, m, pkg);
         else loadAsDirectory(res, function (err, d, pkg) {
             if (err) cb(err);
-            else if (d) cb(null, d, pkg);
-            else {
+            else if (d) {
+                maybeUnwrapSymlink(d, opts, function (err, realD) {
+                    if (err) {
+                        cb(err);
+                    } else {
+                        cb(null, realD, pkg);
+                    }
+                });
+            } else {
                 var moduleError = new Error("Cannot find module '" + x + "' from '" + parent + "'");
                 moduleError.code = 'MODULE_NOT_FOUND';
                 cb(moduleError);

lib/sync.js

@@ -67,12 +67,12 @@ module.exports = function (x, options) {
         var res = path.resolve(absoluteStart, x);
         if (x === '..' || x.slice(-1) === '/') res += '/';
         var m = loadAsFileSync(res) || loadAsDirectorySync(res);
-        if (m) return m;
+        if (m) return maybeUnwrapSymlink(m, opts);
     } else if (core[x]) {
         return x;
     } else {
         var n = loadNodeModulesSync(x, absoluteStart);
-        if (n) return n;
+        if (n) return maybeUnwrapSymlink(n, opts);
     }
 
     if (core[x]) return x;

package.json

@@ -16,6 +16,7 @@
   "scripts": {
     "prepublish": "safe-publish-latest",
     "lint": "eslint .",
+    "pretests-only": "cd ./test/resolver/nested_symlinks && node mylib/sync && node mylib/async",
     "tests-only": "tape test/*.js",
     "pretest": "npm run lint",
     "test": "npm run --silent tests-only",

test/resolver/nested_symlinks/mylib/async.js

@@ -0,0 +1,26 @@
+var a = require.resolve('buffer/').replace(process.cwd(), '$CWD');
+var b;
+var c;
+
+var test = function test() {
+    console.log(a, ': require.resolve, preserveSymlinks ' + (process.execArgv.indexOf('preserve-symlinks') > -1 ? 'true' : 'false'));
+    console.log(b, ': preserveSymlinks true');
+    console.log(c, ': preserveSymlinks false');
+
+    if (a !== b && a !== c) {
+        throw 'async: no match';
+    }
+    console.log('async: success! a matched either b or c\n');
+};
+
+require('resolve')('buffer/', { preserveSymlinks: true }, function (err, result) {
+    if (err) { throw err; }
+    b = result.replace(process.cwd(), '$CWD');
+    if (b && c) { test(); }
+});
+require('resolve')('buffer/', { preserveSymlinks: false }, function (err, result) {
+    if (err) { throw err; }
+    c = result.replace(process.cwd(), '$CWD');
+    if (b && c) { test(); }
+});
+

test/resolver/nested_symlinks/mylib/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "mylib",
+  "version": "0.0.0",
+  "description": "",
+  "private": true,
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "dependencies": {
+    "buffer": "*"
+  }
+}

test/resolver/nested_symlinks/mylib/sync.js

@@ -0,0 +1,12 @@
+var a = require.resolve('buffer/').replace(process.cwd(), '$CWD');
+var b = require('resolve').sync('buffer/', { preserveSymlinks: true }).replace(process.cwd(), '$CWD');
+var c = require('resolve').sync('buffer/', { preserveSymlinks: false }).replace(process.cwd(), '$CWD');
+
+console.log(a, ': require.resolve, preserveSymlinks ' + (process.execArgv.indexOf('preserve-symlinks') > -1 ? 'true' : 'false'));
+console.log(b, ': preserveSymlinks true');
+console.log(c, ': preserveSymlinks false');
+
+if (a !== b && a !== c) {
+    throw 'sync: no match';
+}
+console.log('sync: success! a matched either b or c\n');

test/resolver/symlinked/package/bar.js

@@ -0,0 +1 @@
+module.exports = 'bar';

test/resolver/symlinked/package/package.json

@@ -0,0 +1,3 @@
+{
+    "main": "bar.js"
+}

test/symlinks.js

@@ -4,11 +4,13 @@ var test = require('tape');
 var resolve = require('../');
 
 var symlinkDir = path.join(__dirname, 'resolver', 'symlinked', 'symlink');
+var packageDir = path.join(__dirname, 'resolver', 'symlinked', '_', 'node_modules', 'package');
 try {
     fs.unlinkSync(symlinkDir);
 } catch (err) {}
 try {
     fs.symlinkSync('./_/symlink_target', symlinkDir, 'dir');
+    fs.symlinkSync('../../package', packageDir, 'dir');
 } catch (err) {
     if (err.code !== 'EEXIST') {
         // if fails then it is probably on Windows and lets try to create a junction
@@ -56,3 +58,21 @@ test('sync symlink when preserveSymlinks = true', function (t) {
     }, /Cannot find module 'foo'/);
     t.end();
 });
+
+test('sync symlink from node_modules to other dir when preserveSymlinks = false', function (t) {
+    var basedir = path.join(__dirname, 'resolver', 'symlinked', '_');
+    var fn = resolve.sync('package', { basedir: basedir, preserveSymlinks: false });
+
+    t.equal(fn, path.resolve(__dirname, 'resolver/symlinked/package/bar.js'));
+    t.end();
+});
+
+test('async symlink from node_modules to other dir when preserveSymlinks = false', function (t) {
+    t.plan(2);
+    var basedir = path.join(__dirname, 'resolver', 'symlinked', '_');
+    resolve('package', { basedir: basedir, preserveSymlinks: false }, function (err, result) {
+        t.notOk(err, 'no error');
+        t.equal(result, path.resolve(__dirname, 'resolver/symlinked/package/bar.js'));
+        t.end();
+    });
+});