From 99cdc61c30b1785b18677d33e339abc50017c336 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bengt-Ove=20Holl=C3=A4nder?=
 <Bengt.Ove.Hollaender@gmail.com>
Date: Tue, 3 Oct 2017 07:00:33 +0200
Subject: [PATCH] feat(ConfigReader): Use CLI options with default config file
 (#404)

Use the stryker.conf.js file in the current working directory, if one is present. Display 'Use `stryker init` command to generate your config file.' when stryker is run without a config file.

Closes #390
---
 packages/stryker/src/ConfigReader.ts          | 28 +++++++++++++------
 .../config-reader/ConfigReaderSpec.ts         | 21 ++++++++++----
 2 files changed, 34 insertions(+), 15 deletions(-)

diff --git a/packages/stryker/src/ConfigReader.ts b/packages/stryker/src/ConfigReader.ts
index 55c9ffd94c..904259714e 100644
--- a/packages/stryker/src/ConfigReader.ts
+++ b/packages/stryker/src/ConfigReader.ts
@@ -1,6 +1,8 @@
 import { Config } from 'stryker-api/config';
 import { StrykerOptions } from 'stryker-api/core';
+import * as fs from 'mz/fs';
 import * as log4js from 'log4js';
+import * as path from 'path';
 import * as _ from 'lodash';
 
 const VALID_COVERAGE_ANALYSIS_VALUES = ['perTest', 'all', 'off'];
@@ -11,6 +13,8 @@ export const CONFIG_SYNTAX_HELP = '  module.exports = function(config) {\n' +
   '    });\n' +
   '  };';
 
+const DEFAULT_CONFIG_FILE = 'stryker.conf.js';
+
 const log = log4js.getLogger('ConfigReader');
 
 export default class ConfigReader {
@@ -34,10 +38,22 @@ export default class ConfigReader {
   }
 
   private loadConfigModule(): Function {
-    // we start with a dummy configModule
+    // Dummy module to be returned if no config file is loaded.
     let configModule: Function = function () { };
+
+    if (!this.cliOptions.configFile) {
+      try {
+        fs.accessSync(path.resolve(`./${DEFAULT_CONFIG_FILE}`));
+        log.info(`Using ${DEFAULT_CONFIG_FILE} in the current working directory.`);
+        this.cliOptions.configFile = DEFAULT_CONFIG_FILE;
+      } catch (e) {
+        log.info('No config file specified. Running with command line arguments.');
+        log.info('Use `stryker init` command to generate your config file.');
+      }
+    }
+
     if (this.cliOptions.configFile) {
-      log.debug('Loading config %s', this.cliOptions.configFile);
+      log.debug(`Loading config ${this.cliOptions.configFile}`);
       try {
         configModule = require(`${process.cwd()}/${this.cliOptions.configFile}`);
       } catch (e) {
@@ -55,14 +71,8 @@ export default class ConfigReader {
         log.fatal('Config file must export a function!\n' + CONFIG_SYNTAX_HELP);
         process.exit(1);
       }
-    } else if (Object.keys(this.cliOptions).length === 0) {
-      log.info('Using stryker.conf.js in the current working directory.');
-      this.cliOptions.configFile = 'stryker.conf.js';
-      return this.loadConfigModule();
-    } else {
-      log.info('No config file specified. Running with command line arguments');
-      // if no config file path is passed, we create and return a dummy config module.
     }
+
     return configModule;
   }
 
diff --git a/packages/stryker/test/integration/config-reader/ConfigReaderSpec.ts b/packages/stryker/test/integration/config-reader/ConfigReaderSpec.ts
index e200ffe15c..6a56dd4640 100644
--- a/packages/stryker/test/integration/config-reader/ConfigReaderSpec.ts
+++ b/packages/stryker/test/integration/config-reader/ConfigReaderSpec.ts
@@ -49,14 +49,15 @@ describe('ConfigReader', () => {
         });
 
         describe('without a stryker.conf.js in the CWD', () => {
-          it('should report a fatal error', () => {
+          it('should return default config', () => {
             let mockCwd = process.cwd() + '/testResources/config-reader/no-config';
             sandbox.stub(process, 'cwd').returns(mockCwd);
+
             sut = new ConfigReader({});
 
             result = sut.readConfig(); 
 
-            expect(log.fatal).to.have.been.calledWith(`File ${mockCwd}/stryker.conf.js does not exist!`);
+            expect(result).to.deep.equal(new Config());
           });
         });
       });
@@ -77,17 +78,25 @@ describe('ConfigReader', () => {
     });
 
     describe('with config file', () => {
-
-      beforeEach(() => {
+      it('should read config file', () => {
         sut = new ConfigReader({ configFile: 'testResources/config-reader/valid.conf.js' });
+
         result = sut.readConfig();
-      });
 
-      it('should read config file', () => {
         expect(result['valid']).to.be.eq('config');
         expect(result['should']).to.be.eq('be');
         expect(result['read']).to.be.eq(true);
       });
+
+      describe('with CLI options', () => {
+        it('should give precedence to CLI options', () => {
+          sut = new ConfigReader({ configFile: 'testResources/config-reader/valid.conf.js', read: false });
+
+          result = sut.readConfig();
+
+          expect(result['read']).to.be.eq(false);
+        });
+      });
     });
 
     describe('with non-existing config file', () => {