Remove unnecessary require.cache munging in runtime test

test/runtime.js

 var assert = require('assert'),
-  extensionsPath = process.env.NODESASS_COV
-      ? require.resolve('../lib-cov/extensions')
-      : require.resolve('../lib/extensions');
+  sass = process.env.NODESASS_COV
+      ? require('../lib-cov/extensions')
+      : require('../lib/extensions');
 
 describe('runtime parameters', function() {
-  var packagePath = require.resolve('../package'),
+  var pkg = require('../package'),
         // Let's use JSON to fake a deep copy
     savedArgv = JSON.stringify(process.argv),
     savedEnv = JSON.stringify(process.env);
 
-  beforeEach(function() {
-    require(packagePath);
-    delete require.cache[extensionsPath];
-  });
-
   afterEach(function() {
-    delete require.cache[packagePath];
-    delete require.cache[extensionsPath];
     process.argv = JSON.parse(savedArgv);
     process.env = JSON.parse(savedEnv);
-    require(packagePath);
+    delete pkg.nodeSassConfig;
   });
 
   describe('configuration precedence should be respected', function() {
@@ -29,24 +22,21 @@ describe('runtime parameters', function() {
         process.argv.push('--sass-binary-name', 'aaa');
         process.env.SASS_BINARY_NAME = 'bbb';
         process.env.npm_config_sass_binary_name = 'ccc';
-        require.cache[packagePath].exports.nodeSassConfig = { binaryName: 'ddd' };
+        pkg.nodeSassConfig = { binaryName: 'ddd' };
       });
 
       it('command line argument', function() {
-        var sass = require(extensionsPath);
         assert.equal(sass.getBinaryName(), 'aaa_binding.node');
       });
 
       it('environment variable', function() {
         process.argv = [];
-        var sass = require(extensionsPath);
         assert.equal(sass.getBinaryName(), 'bbb_binding.node');
       });
 
       it('npm config variable', function() {
         process.argv = [];
         process.env.SASS_BINARY_NAME = null;
-        var sass = require(extensionsPath);
         assert.equal(sass.getBinaryName(), 'ccc_binding.node');
       });
 
@@ -54,7 +44,6 @@ describe('runtime parameters', function() {
         process.argv = [];
         process.env.SASS_BINARY_NAME = null;
         process.env.npm_config_sass_binary_name = null;
-        var sass = require(extensionsPath);
         assert.equal(sass.getBinaryName(), 'ddd_binding.node');
       });
     });
@@ -64,18 +53,16 @@ describe('runtime parameters', function() {
         process.argv.push('--sass-binary-site', 'http://aaa.example.com:9999');
         process.env.SASS_BINARY_SITE = 'http://bbb.example.com:8888';
         process.env.npm_config_sass_binary_site = 'http://ccc.example.com:7777';
-        require.cache[packagePath].exports.nodeSassConfig = { binarySite: 'http://ddd.example.com:6666' };
+        pkg.nodeSassConfig = { binarySite: 'http://ddd.example.com:6666' };
       });
 
       it('command line argument', function() {
-        var sass = require(extensionsPath);
         var URL = 'http://aaa.example.com:9999';
         assert.equal(sass.getBinaryUrl().substr(0, URL.length), URL);
       });
 
       it('environment variable', function() {
         process.argv = [];
-        var sass = require(extensionsPath);
         var URL = 'http://bbb.example.com:8888';
         assert.equal(sass.getBinaryUrl().substr(0, URL.length), URL);
       });
@@ -83,7 +70,6 @@ describe('runtime parameters', function() {
       it('npm config variable', function() {
         process.argv = [];
         process.env.SASS_BINARY_SITE = null;
-        var sass = require(extensionsPath);
         var URL = 'http://ccc.example.com:7777';
         assert.equal(sass.getBinaryUrl().substr(0, URL.length), URL);
       });
@@ -92,7 +78,6 @@ describe('runtime parameters', function() {
         process.argv = [];
         process.env.SASS_BINARY_SITE = null;
         process.env.npm_config_sass_binary_site = null;
-        var sass = require(extensionsPath);
         var URL = 'http://ddd.example.com:6666';
         assert.equal(sass.getBinaryUrl().substr(0, URL.length), URL);
       });
@@ -103,24 +88,21 @@ describe('runtime parameters', function() {
         process.argv.push('--sass-binary-path', 'aaa_binding.node');
         process.env.SASS_BINARY_PATH = 'bbb_binding.node';
         process.env.npm_config_sass_binary_path = 'ccc_binding.node';
-        require.cache[packagePath].exports.nodeSassConfig = { binaryPath: 'ddd_binding.node' };
+        pkg.nodeSassConfig = { binaryPath: 'ddd_binding.node' };
       });
 
       it('command line argument', function() {
-        var sass = require(extensionsPath);
         assert.equal(sass.getBinaryPath(), 'aaa_binding.node');
       });
 
       it('environment variable', function() {
         process.argv = [];
-        var sass = require(extensionsPath);
         assert.equal(sass.getBinaryPath(), 'bbb_binding.node');
       });
 
       it('npm config variable', function() {
         process.argv = [];
         process.env.SASS_BINARY_PATH = null;
-        var sass = require(extensionsPath);
         assert.equal(sass.getBinaryPath(), 'ccc_binding.node');
       });
 
@@ -128,7 +110,6 @@ describe('runtime parameters', function() {
         process.argv = [];
         process.env.SASS_BINARY_PATH = null;
         process.env.npm_config_sass_binary_path = null;
-        var sass = require(extensionsPath);
         assert.equal(sass.getBinaryPath(), 'ddd_binding.node');
       });
     });