From 532d89c1f69ca30da6edefb0da174bfc3dfde9dc Mon Sep 17 00:00:00 2001
From: Philipp Muens <raute1337@gmx.de>
Date: Thu, 30 Mar 2017 09:57:02 +0200
Subject: [PATCH] Update tests to be side-effect free

Use proxyquire and stubbing to make the tests side-effect free. This way the tests will succeed even when someone who runs the tests has the serverless-alpha plugin installed globally.
---
 lib/classes/PluginManager.js      | 14 +++----
 lib/classes/PluginManager.test.js | 61 ++++++++++++++++++++++---------
 2 files changed, 48 insertions(+), 27 deletions(-)

diff --git a/lib/classes/PluginManager.js b/lib/classes/PluginManager.js
index e6b2c8949..252cb935c 100644
--- a/lib/classes/PluginManager.js
+++ b/lib/classes/PluginManager.js
@@ -31,20 +31,16 @@ class PluginManager {
     }
 
     try {
-      const prefixPath = childProcess.execSync('npm config get prefix --silent').toString().trim();
+      let prefixPath = childProcess.execSync('npm config get prefix --silent').toString().trim();
 
       if (prefixPath && prefixPath.length) {
-        // get the path to the global node_modules dir
-        // see: https://docs.npmjs.com/files/folders
-        let globalNodeModulesPath;
-        if (os.platform === 'win32') {
-          globalNodeModulesPath = prefixPath;
-        } else {
-          globalNodeModulesPath = path.join(prefixPath, 'lib');
+        // get the path to the global node_modules dir (see: https://docs.npmjs.com/files/folders)
+        if (os.platform !== 'win32') {
+          prefixPath = path.join(prefixPath, 'lib');
         }
 
         const serverlessAlphaPluginPath = resolveFrom(
-          globalNodeModulesPath,
+          prefixPath,
           'serverless-alpha'
         );
 
diff --git a/lib/classes/PluginManager.test.js b/lib/classes/PluginManager.test.js
index bc07c8f53..16e31ee95 100644
--- a/lib/classes/PluginManager.test.js
+++ b/lib/classes/PluginManager.test.js
@@ -14,6 +14,7 @@ const mockRequire = require('mock-require');
 const testUtils = require('../../tests/utils');
 const os = require('os');
 const sinon = require('sinon');
+const proxyquire = require('proxyquire');
 
 describe('PluginManager', () => {
   let pluginManager;
@@ -327,19 +328,25 @@ describe('PluginManager', () => {
     beforeEach(() => {
       tmpDirPath = testUtils.getTmpDirPath();
       fse.mkdirsSync(tmpDirPath);
-      serverless.config.servicePath = tmpDirPath;
-    });
-
-    afterEach(() => {
       serverless.config.servicePath = false;
     });
 
     describe('when serverless-alpha is installed locally', () => {
       beforeEach(() => {
+        serverless.config.servicePath = tmpDirPath;
         const pluginPath = path.join(tmpDirPath, 'node_modules', 'serverless-alpha');
 
         class ServerlessAlpha {}
         testUtils.installPlugin(pluginPath, ServerlessAlpha);
+
+        const resolveFromStub = sinon.stub()
+          .withArgs(serverless.config.servicePath, 'serverless-alpha')
+          .returns(pluginPath);
+        const ModifiedPluginManager = proxyquire('./PluginManager.js', {
+          'resolve-from': resolveFromStub,
+        });
+
+        pluginManager = new ModifiedPluginManager(serverless);
       });
 
       it('should auto-load the plugin', () => {
@@ -352,7 +359,6 @@ describe('PluginManager', () => {
 
     describe('when running on a UNIX machine', () => {
       let npmStub;
-      let prefixPath;
       let globalNodeModulesPath;
 
       beforeEach(() => {
@@ -360,9 +366,24 @@ describe('PluginManager', () => {
           .withArgs('npm config get prefix --silent')
           .returns(tmpDirPath);
 
-        prefixPath = tmpDirPath;
-        globalNodeModulesPath = path.join(prefixPath, 'lib', 'node_modules');
-        fse.mkdirsSync(path.join(prefixPath, 'lib', 'node_modules'));
+        const prefixPath = path.join(tmpDirPath, 'lib');
+        globalNodeModulesPath = path.join(prefixPath, 'node_modules');
+        fse.mkdirsSync(globalNodeModulesPath);
+
+        // add a mock for the serverless-alpha plugin in the tmpDir
+        class ServerlessAlpha {}
+        const globalAlphaPluginPath = path.join(globalNodeModulesPath, 'serverless-alpha');
+        fse.mkdirsSync(globalAlphaPluginPath);
+        testUtils.installPlugin(globalAlphaPluginPath, ServerlessAlpha);
+
+        const resolveFromStub = sinon.stub();
+        resolveFromStub.withArgs(serverless.config.servicePath, 'serverless-alpha').returns(false);
+        resolveFromStub.withArgs(prefixPath, 'serverless-alpha').returns(globalAlphaPluginPath);
+        const ModifiedPluginManager = proxyquire('./PluginManager.js', {
+          'resolve-from': resolveFromStub,
+        });
+
+        pluginManager = new ModifiedPluginManager(serverless);
       });
 
       afterEach(() => {
@@ -370,13 +391,6 @@ describe('PluginManager', () => {
       });
 
       it('should auto load the plugin if globally installed via npm', () => {
-        // add a mock for the serverless-alpha plugin in the tmpDir
-        class ServerlessAlpha {}
-        const globalAlphaPluginPath = path.join(globalNodeModulesPath, 'serverless-alpha');
-
-        fse.mkdirsSync(globalAlphaPluginPath);
-        testUtils.installPlugin(globalAlphaPluginPath, ServerlessAlpha);
-
         pluginManager.autoloadServerlessAlphaPlugin();
 
         expect(npmStub.calledWithExactly('npm config get prefix --silent')).to.equal(true);
@@ -385,10 +399,21 @@ describe('PluginManager', () => {
       });
     });
 
-    it('should not load the serverless-alpha plugin if not installed', () => {
-      pluginManager.autoloadServerlessAlphaPlugin();
+    describe('when serverless-alpha is not installed at all', () => {
+      beforeEach(() => {
+        const resolveFromStub = sinon.stub().returns(false);
+        const ModifiedPluginManager = proxyquire('./PluginManager.js', {
+          'resolve-from': resolveFromStub,
+        });
 
-      expect(pluginManager.plugins.length).to.equal(0);
+        pluginManager = new ModifiedPluginManager(serverless);
+      });
+
+      it('should not load the serverless-alpha plugin if not installed', () => {
+        pluginManager.autoloadServerlessAlphaPlugin();
+
+        expect(pluginManager.plugins.length).to.equal(0);
+      });
     });
   });