feat: add option to exclude directories from index.js (#50)

* Add option to exclude directories from index.js
* Update readDirectory.js
* Update writeIndexCli.js
* Update readDirectory.js
* Update README

.editorconfig

@@ -1,7 +1,9 @@
 root = true
 
 [*]
+charset = utf-8
 end_of_line = lf
-insert_final_newline = true
-indent_style = space
 indent_size = 2
+indent_style = space
+insert_final_newline = true
+trim_trailing_whitespace = true

.gitattributes

@@ -0,0 +1 @@
+* text eol=lf

README.md

@@ -36,8 +36,8 @@ This created `index.js` with:
 ```js
 // @create-index
 
-export bar from './bar.js';
+export { default as bar } from './bar.js';
-export foo from './foo.js';
+export { default as foo } from './foo.js';
 
 ```
 
@@ -66,9 +66,9 @@ This have updated `index.js` file:
 ```js
 // @create-index
 
-export bar from './bar.js';
+export { default as bar } from './bar.js';
-export baz from './baz.js';
+export { default as baz } from './baz.js';
-export foo from './foo.js';
+export { default as foo } from './foo.js';
 
 ```
 
@@ -82,21 +82,34 @@ npm install create-index
 create-index --help
 
 Options:
-  --recursive, -r     Create/update index files recursively. Halts on any unsafe
+  --recursive, -r          Create/update index files recursively. Halts on any
-                      "index.js" files.               [boolean] [default: false]
+                           unsafe "index.js" files.   [boolean] [default: false]
-  --ignoreUnsafe, -i  Ignores unsafe "index.js" files instead of halting.
+  --ignoreUnsafe, -i       Ignores unsafe "index.js" files instead of halting.
                                                       [boolean] [default: false]
-  --update, -u        Updates only previously created index files (recursively).
+  --ignoreDirectories, -d  Ignores importing directories into the index file,
+                           even if they have a safe "index.js".
                                                       [boolean] [default: false]
-  --banner            Add a custom banner at the top of the index file  [string]
+  --update, -u             Updates only previously created index files
+                           (recursively).             [boolean] [default: false]
+  --banner                 Add a custom banner at the top of the index file
+                                                                        [string]
+  --extensions, -x         Allows some extensions to be parsed as valid source.
+                           First extension will always be preferred to homonyms
+                           with another allowed extension.
+                                                       [array] [default: ["js"]]
 
 Examples:
-  create-index ./src ./src/utilities   Creates or updates an existing
+  create-index ./src ./src/utilities      Creates or updates an existing
-                                       create-index index file in the target
+                                          create-index index file in the target
-                                       (./src, ./src/utilities) directories.
+                                          (./src, ./src/utilities) directories.
-  create-index --update ./src ./tests  Finds all create-index index files in the
+  create-index --update ./src ./tests     Finds all create-index index files in
-                                       target directories and descending
+                                          the target directories and descending
-                                       directories. Updates found index files.
+                                          directories. Updates found index
+                                          files.
+  create-index ./src --extensions js jsx  Creates or updates an existing
+                                          create-index index file in the target
+                                          (./src) directory for both .js and
+                                          .jsx extensions.
 ```
 
 ### Using `create-index` Programmatically
@@ -177,8 +190,8 @@ Given the above directory contents, `./index.js` will be:
 ```js
 // @create-index
 
-import bar from './bar';
+import { default as bar } from './bar';
-import foo from './foo.js';
+import { default as foo } from './foo.js';
 
 export {
     bar,
@@ -193,3 +206,37 @@ Directories that do not have `./index.js` in themselves will be excluded.
 When run again, `create-index` will update existing `./index.js` if it starts with `// @create-index\n\n`.
 
 If `create-index` is executed against a directory that contains `./index.js`, which does not start with `// @create-index\n\n`, an error will be thrown.
+
+## Ignore files on `--update`
+
+`create-index` can ignore files in a directory if `./index.js` contains special object with defined `ignore` property which takes `an array` of `regular expressions` defined as `strings`, e.g.
+
+```js
+> cat index.js
+// @create-index {"ignore": ["/baz.js$/"]}
+```
+
+```js
+> tree ./
+./
+├── bar.js
+├── baz.js
+├── foo.js
+└── index.js
+
+0 directories, 4 files
+```
+
+Given the above directory contents, after running `create-index` with `--update` flag, `./index.js` will be:
+
+```js
+// @create-index {"ignore": ["/baz.js$/"]}
+
+import { default as bar } from './bar.js';
+import { default as foo } from './foo.js';
+
+export {
+    bar,
+    foo
+};
+```

package.json

@@ -21,6 +21,7 @@
     "babel-plugin-transform-export-extensions": "^6.8.0",
     "babel-register": "^6.18.0",
     "chai": "^3.5.0",
+    "cross-env": "^3.1.3",
     "eslint": "^3.9.1",
     "eslint-config-canonical": "^4.0.0",
     "husky": "^0.11.9",
@@ -43,11 +44,11 @@
     "url": "https://github.com/gajus/create-index"
   },
   "scripts": {
-    "build": "NODE_ENV=production babel --source-maps --copy-files ./src --out-dir ./dist",
+    "build": "cross-env NODE_ENV=production babel --source-maps --copy-files ./src --out-dir ./dist",
     "create-index": "node ./dist/bin/create-index ./src/utilities",
-    "lint": "NODE_ENV=development eslint ./src ./tests",
+    "lint": "cross-env NODE_ENV=development eslint ./src ./tests",
     "precommit": "npm run test",
-    "test": "npm run build && npm run lint && NODE_ENV=development mocha --compilers js:babel-register"
+    "test": "npm run build && npm run lint && cross-env NODE_ENV=development mocha --compilers js:babel-register"
   },
-  "version": "1.0.0"
+  "version": "1.1.0"
 }

src/bin/create-index.js

@@ -23,6 +23,14 @@ const argv = yargs
       type: 'boolean'
     }
   })
+  .options({
+    ignoreDirectories: {
+      alias: 'd',
+      default: false,
+      description: 'Ignores importing directories into the index file, even if they have a safe "index.js".',
+      type: 'boolean'
+    }
+  })
   .options({
     update: {
       alias: 'u',
@@ -37,12 +45,32 @@ const argv = yargs
       type: 'string'
     }
   })
-  .example('create-index ./src ./src/utilities', 'Creates or updates an existing create-index index file in the target (./src, ./src/utilities) directories.')
+  .options({
-  .example('create-index --update ./src ./tests', 'Finds all create-index index files in the target directories and descending directories. Updates found index files.')
+    extensions: {
+      alias: 'x',
+      default: ['js'],
+      description: 'Allows some extensions to be parsed as valid source. First extension will always be preferred to homonyms with another allowed extension.',
+      type: 'array'
+    }
+  })
+  .example(
+    'create-index ./src ./src/utilities',
+    'Creates or updates an existing create-index index file in the target (./src, ./src/utilities) directories.'
+  )
+  .example(
+    'create-index --update ./src ./tests',
+    'Finds all create-index index files in the target directories and descending directories. Updates found index files.'
+  )
+  .example(
+    'create-index ./src --extensions js jsx',
+    'Creates or updates an existing create-index index file in the target (./src) directory for both .js and .jsx extensions.'
+  )
   .argv;
 
 writeIndexCli(argv._, {
   banner: argv.banner,
+  extensions: argv.extensions,
+  ignoreDirectories: argv.ignoreDirectories,
   ignoreUnsafe: argv.ignoreUnsafe,
   recursive: argv.recursive,
   updateIndex: argv.update

src/utilities/constants.js

@@ -0,0 +1,2 @@
+// eslint-disable-next-line
+export const CREATE_INDEX_PATTERN = /(?:^|[\n\r]+)\/\/ @create-index\s?({.*})?[\n\r]+/;

src/utilities/createIndexCode.js

@@ -14,7 +14,7 @@ const buildExportBlock = (files) => {
   let importBlock;
 
   importBlock = _.map(files, (fileName) => {
-    return 'export ' + safeVariableName(fileName) + ' from \'./' + fileName + '\';';
+    return 'export { default as ' + safeVariableName(fileName) + ' } from \'./' + fileName + '\';';
   });
 
   importBlock = importBlock.join('\n');
@@ -24,8 +24,10 @@ const buildExportBlock = (files) => {
 
 export default (filePaths, options = {}) => {
   let code;
+  let configCode;
 
   code = '';
+  configCode = '';
 
   if (options.banner) {
     const banners = _.isArray(options.banner) ? options.banner : [options.banner];
@@ -37,7 +39,11 @@ export default (filePaths, options = {}) => {
     code += '\n';
   }
 
-  code += '// @create-index\n\n';
+  if (options.config && _.size(options.config) > 0) {
+    configCode += ' ' + JSON.stringify(options.config);
+  }
+
+  code += '// @create-index' + configCode + '\n\n';
 
   if (filePaths.length) {
     const sortedFilePaths = filePaths.sort();

src/utilities/hasIndex.js

@@ -0,0 +1,14 @@
+import fs from 'fs';
+import path from 'path';
+
+export default (directoryPath) => {
+  const indexPath = path.resolve(directoryPath, 'index.js');
+
+  try {
+    fs.statSync(indexPath);
+
+    return true;
+  } catch (error) {
+    return false;
+  }
+};

src/utilities/index.js

@@ -1,10 +1,10 @@
 // @create-index
 
-export createIndexCode from './createIndexCode.js';
+export createIndexCode from './createIndexCode';
-export findIndexFiles from './findIndexFiles.js';
+export findIndexFiles from './findIndexFiles';
-export log from './log.js';
+export log from './log';
-export readDirectory from './readDirectory.js';
+export readDirectory from './readDirectory';
-export sortByDepth from './sortByDepth.js';
+export sortByDepth from './sortByDepth';
-export validateTargetDirectory from './validateTargetDirectory.js';
+export validateTargetDirectory from './validateTargetDirectory';
-export writeIndex from './writeIndex.js';
+export writeIndex from './writeIndex';
-export writeIndexCli from './writeIndexCli.js';
+export writeIndexCli from './writeIndexCli';

src/utilities/log.js

@@ -2,8 +2,6 @@ import chalk from 'chalk';
 import moment from 'moment';
 
 export default (...append) => {
-    /* eslint-disable no-console */
+  // eslint-disable-next-line
   console.log(chalk.dim('[' + moment().format('HH:mm:ss') + ']'), ...append);
-
-    /* eslint-enable no-console */
 };

src/utilities/readDirectory.js

@@ -1,20 +1,9 @@
 import fs from 'fs';
 import path from 'path';
 import _ from 'lodash';
+import hasIndex from './hasIndex';
 import validateTargetDirectory from './validateTargetDirectory';
 
-const hasIndex = (directoryPath) => {
-  const indexPath = path.resolve(directoryPath, 'index.js');
-
-  try {
-    fs.statSync(indexPath);
-
-    return true;
-  } catch (error) {
-    return false;
-  }
-};
-
 const hasNoExtension = (fileName) => {
   const matches = fileName.match(/\./g);
 
@@ -31,19 +20,70 @@ const isSafeName = (fileName) => {
   return /^[a-z][a-z0-9._]+$/i.test(fileName);
 };
 
-const removeDuplicates = (files) => {
+const stripExtension = (fileName) => {
+  const pos = fileName.lastIndexOf('.');
+
+  if (pos === -1) {
+    return fileName;
+  }
+
+  return fileName.substr(0, pos);
+};
+
+const removeDuplicates = (files, preferredExtension) => {
   return _.filter(files, (fileName) => {
-    return !_.includes(files, fileName + '.js');
+    const withoutExtension = stripExtension(fileName);
+    const mainAlternative = withoutExtension + '.' + preferredExtension;
+
+    if (mainAlternative === fileName) {
+      return true;
+    }
+
+    return !_.includes(files, mainAlternative);
+  });
+};
+
+const removeIgnoredFiles = (files, ignorePatterns = []) => {
+  if (ignorePatterns.length === 0) {
+    return files;
+  }
+
+  const patterns = ignorePatterns.map((pattern) => {
+    if (_.startsWith(pattern, '/') && _.endsWith(pattern, '/')) {
+      const patternWithoutSlashes = pattern.slice(1, -1);
+
+      return new RegExp(patternWithoutSlashes);
+    }
+
+    return new RegExp(pattern);
+  });
+
+  return _.filter(files, (fileName) => {
+    let pattern;
+
+    for (pattern of patterns) {
+      if (fileName.match(pattern) !== null) {
+        return false;
+      }
+    }
+
+    return true;
   });
 };
 
 export default (directoryPath, options = {}) => {
-  let children;
-
   if (!validateTargetDirectory(directoryPath, {silent: options.silent})) {
     return false;
   }
 
+  const {
+    extensions = ['js'],
+    config = {},
+    ignoreDirectories = false
+  } = options;
+
+  let children;
+
   children = fs.readdirSync(directoryPath);
 
   children = _.filter(children, (fileName) => {
@@ -66,18 +106,21 @@ export default (directoryPath, options = {}) => {
       return false;
     }
 
-    if (!isDirectory && !_.endsWith(fileName, '.js')) {
+    if (!isDirectory && !extensions.some((ext) => {
+      return _.endsWith(fileName, '.' + ext);
+    })) {
       return false;
     }
 
-    if (isDirectory && !hasIndex(absolutePath)) {
+    if (isDirectory && (!hasIndex(absolutePath) || ignoreDirectories)) {
       return false;
     }
 
     return true;
   });
 
-  children = removeDuplicates(children);
+  children = removeDuplicates(children, extensions[0]);
+  children = removeIgnoredFiles(children, config.ignore);
 
   return children.sort();
 };

src/utilities/readIndexConfig.js

@@ -0,0 +1,32 @@
+import fs from 'fs';
+import path from 'path';
+import hasIndex from './hasIndex';
+import {CREATE_INDEX_PATTERN} from './constants';
+
+export default (directoryPath) => {
+  if (!hasIndex(directoryPath)) {
+    return {};
+  }
+
+  const indexPath = path.resolve(directoryPath, 'index.js');
+  const indexContents = fs.readFileSync(indexPath, 'utf-8');
+  const found = indexContents.match(CREATE_INDEX_PATTERN);
+  const configLine = typeof found[1] === 'string' ? found[1].trim() : '';
+
+  if (configLine.length === 0) {
+    return {};
+  }
+
+  let config;
+
+  try {
+    config = JSON.parse(configLine);
+  } catch (error) {
+    throw new Error(
+      '"' + indexPath + '" contains invalid configuration object.\n' +
+      'Configuration object must be a valid JSON.'
+    );
+  }
+
+  return config;
+};

src/utilities/validateTargetDirectory.js

@@ -1,5 +1,6 @@
 import fs from 'fs';
 import path from 'path';
+import {CREATE_INDEX_PATTERN} from './constants';
 
 export default (targetDirectory, options = {}) => {
   const silent = options.silent;
@@ -33,7 +34,7 @@ export default (targetDirectory, options = {}) => {
 
   const indexFile = fs.readFileSync(indexFilePath, 'utf8');
 
-  if (!indexFile.match(/(?:^|[\n\r]+)\/\/ @create-index[\n\r]+/)) {
+  if (!indexFile.match(CREATE_INDEX_PATTERN)) {
     if (silent) {
       return false;
     } else {

src/utilities/writeIndex.js

@@ -4,6 +4,7 @@ import _ from 'lodash';
 import createIndexCode from './createIndexCode';
 import validateTargetDirectory from './validateTargetDirectory';
 import readDirectory from './readDirectory';
+import readIndexConfig from './readIndexConfig';
 import sortByDepth from './sortByDepth';
 
 export default (directoryPaths, options = {}) => {
@@ -13,8 +14,10 @@ export default (directoryPaths, options = {}) => {
     });
 
   _.forEach(sortedDirectoryPaths, (directoryPath) => {
-    const siblings = readDirectory(directoryPath);
+    const config = readIndexConfig(directoryPath);
-    const indexCode = createIndexCode(siblings);
+    const optionsWithConfig = Object.assign({}, options, {config});
+    const siblings = readDirectory(directoryPath, optionsWithConfig);
+    const indexCode = createIndexCode(siblings, optionsWithConfig);
     const indexFilePath = path.resolve(directoryPath, 'index.js');
 
     fs.writeFileSync(indexFilePath, indexCode);

src/utilities/writeIndexCli.js

@@ -5,6 +5,7 @@ import chalk from 'chalk';
 import createIndexCode from './createIndexCode';
 import validateTargetDirectory from './validateTargetDirectory';
 import readDirectory from './readDirectory';
+import readIndexConfig from './readIndexConfig';
 import sortByDepth from './sortByDepth';
 import log from './log';
 import findIndexFiles from './findIndexFiles';
@@ -18,8 +19,9 @@ export default (directoryPaths, options = {}) => {
   if (options.updateIndex) {
     log('Update index:', options.updateIndex ? chalk.green('true') : chalk.red('false'));
   } else {
-    log('Recursive:', options.ignoreUnsafe ? chalk.green('true') : chalk.red('false'));
+    log('Recursive:', options.recursive ? chalk.green('true') : chalk.red('false'));
     log('Ignore unsafe:', options.ignoreUnsafe ? chalk.green('true') : chalk.red('false'));
+    log('Extensions:', chalk.green(options.extensions));
   }
 
   if (options.updateIndex || options.recursive) {
@@ -43,10 +45,18 @@ export default (directoryPaths, options = {}) => {
   _.forEach(sortedDirectoryPaths, (directoryPath) => {
     let existingIndexCode;
 
-    const siblings = readDirectory(directoryPath, {silent: options.ignoreUnsafe});
+    const config = readIndexConfig(directoryPath);
+
+    const siblings = readDirectory(directoryPath, {
+      config,
+      extensions: options.extensions,
+      ignoreDirectories: options.ignoreDirectories,
+      silent: options.ignoreUnsafe
+    });
 
     const indexCode = createIndexCode(siblings, {
-      banner: options.banner
+      banner: options.banner,
+      config
     });
 
     const indexFilePath = path.resolve(directoryPath, 'index.js');
@@ -64,7 +74,7 @@ export default (directoryPaths, options = {}) => {
     fs.writeFileSync(indexFilePath, indexCode);
 
     if (existingIndexCode && existingIndexCode === indexCode) {
-      log(indexFilePath, chalk.yellow('[index have not changed]'));
+      log(indexFilePath, chalk.yellow('[index has not changed]'));
     } else if (existingIndexCode && existingIndexCode !== indexCode) {
       log(indexFilePath, chalk.green('[updated index]'));
     } else {

test/createIndexCode.js

@@ -12,7 +12,7 @@ describe('createIndexCode()', () => {
 
     expect(indexCode).to.equal(codeExample(`
 // @create-index
-        `));
+    `));
   });
   it('describes a single child', () => {
     const indexCode = createIndexCode(['foo']);
@@ -20,8 +20,8 @@ describe('createIndexCode()', () => {
     expect(indexCode).to.equal(codeExample(`
 // @create-index
 
-export foo from './foo';
+export { default as foo } from './foo';
-        `));
+    `));
   });
   it('describes multiple children', () => {
     const indexCode = createIndexCode(['bar', 'foo']);
@@ -29,9 +29,9 @@ export foo from './foo';
     expect(indexCode).to.equal(codeExample(`
 // @create-index
 
-export bar from './bar';
+export { default as bar } from './bar';
-export foo from './foo';
+export { default as foo } from './foo';
-        `));
+    `));
   });
   context('file with extension', () => {
     it('removes the extension from the export statement', () => {
@@ -40,8 +40,8 @@ export foo from './foo';
       expect(indexCode).to.equal(codeExample(`
 // @create-index
 
-export foo from './foo.js';
+export { default as foo } from './foo.js';
-            `));
+      `));
     });
   });
   context('multiple, unsorted', () => {
@@ -51,9 +51,25 @@ export foo from './foo.js';
       expect(indexCode).to.equal(codeExample(`
 // @create-index
 
-export bar from './bar';
+export { default as bar } from './bar';
-export foo from './foo';
+export { default as foo } from './foo';
-            `));
+      `));
+    });
+  });
+
+  context('with config', () => {
+    it('should append config', () => {
+      const config = {
+        ignore: ['/^zoo/']
+      };
+      const indexCode = createIndexCode(['foo', 'bar'], {config});
+
+      expect(indexCode).to.equal(codeExample(`
+// @create-index {"ignore":["/^zoo/"]}
+
+export { default as bar } from './bar';
+export { default as foo } from './foo';
+      `));
     });
   });
 });

test/fixtures/read-index-config/with-config/index.js

@@ -0,0 +1 @@
+// @create-index {"ignore": ["/foo.js$/"]}

test/fixtures/read-index-config/with-invalid-config/index.js

@@ -0,0 +1 @@
+// @create-index {ignore: 'foo'}

test/fixtures/read-index-config/without-config/index.js

@@ -0,0 +1 @@
+// @create-index

test/fixtures/validate-target-directory/safe-index-with-banner/index.js

@@ -0,0 +1,3 @@
+/* eslint-disable */
+
+// @create-index

test/fixtures/write-index/mixed/index.js

@@ -1,5 +1,5 @@
 // @create-index
 
-export bar from './bar';
+export { default as bar } from './bar';
-export foo from './foo.js';
+export { default as foo } from './foo.js';
 

test/fixtures/write-index/with-config/index.js

@@ -0,0 +1,4 @@
+// @create-index {"ignore":["/bar.js$/"]}
+
+export { default as foo } from './foo.js';
+

test/readDirectory.js

@@ -34,6 +34,12 @@ describe('readDirectory()', () => {
 
       expect(names).to.deep.equal(['bar', 'foo']);
     });
+
+    it('excludes directories if ignoreDirectories = true', () => {
+      const names = readDirectory(path.resolve(fixturesPath, 'children-index'), {ignoreDirectories: true});
+
+      expect(names).to.deep.equal([]);
+    });
   });
   context('target directory contains files', () => {
     it('refers to the files (with extension)', () => {
@@ -49,6 +55,45 @@ describe('readDirectory()', () => {
       expect(names).to.deep.equal(['present.js']);
     });
   });
+  context('target directory contains non js files, and not configured to allow that', () => {
+    it('prefers file', () => {
+      const names = readDirectory(path.resolve(fixturesPath, 'children-files-alt-extension'));
+
+      expect(names).to.deep.equal(['present.js']);
+    });
+  });
+  context('target directory contains non js files, and allowing only jsx', () => {
+    it('prefers file', () => {
+      const options = { extensions: ['jsx'] };
+      const names = readDirectory(path.resolve(fixturesPath, 'children-files-alt-extension'), options);
+
+      expect(names).to.deep.equal(['bar.jsx']);
+    });
+  });
+  context('target directory contains non js files, and allowing both js and jsx', () => {
+    it('prefers file', () => {
+      const options = { extensions: ['js', 'jsx'] };
+      const names = readDirectory(path.resolve(fixturesPath, 'children-files-alt-extension'), options);
+
+      expect(names).to.deep.equal(['bar.jsx', 'present.js']);
+    });
+  });
+  context('target directory contains homonyms files, and allowing both js and jsx, will prefer JS as it is first extension listed', () => {
+    it('prefers file', () => {
+      const options = { extensions: ['js', 'jsx'] };
+      const names = readDirectory(path.resolve(fixturesPath, 'children-files-alt-extension-with-homonyms'), options);
+
+      expect(names).to.deep.equal(['bar.js', 'present.js']);
+    });
+  });
+  context('target directory contains homonyms files, and allowing both js and jsx, will prefer JSX as it is first extension listed', () => {
+    it('prefers file', () => {
+      const options = { extensions: ['jsx', 'js'] };
+      const names = readDirectory(path.resolve(fixturesPath, 'children-files-alt-extension-with-homonyms'), options);
+
+      expect(names).to.deep.equal(['bar.jsx', 'present.js']);
+    });
+  });
   context('target directory contains files with no extension', () => {
     it('ignores files', () => {
       const names = readDirectory(path.resolve(fixturesPath, 'children-files-no-extension'));

test/readIndexConfig.js

@@ -0,0 +1,56 @@
+import path from 'path';
+import {
+    expect
+} from 'chai';
+import readIndexConfig from '../src/utilities/readIndexConfig';
+
+const fixtures = {
+  noIndex: path.resolve(__dirname, 'fixtures/read-index-config/no-index'),
+  withConfig: path.resolve(__dirname, 'fixtures/read-index-config/with-config'),
+  withInvalidConfig: path.resolve(__dirname, 'fixtures/read-index-config/with-invalid-config'),
+  withoutConfig: path.resolve(__dirname, 'fixtures/read-index-config/without-config')
+};
+
+const expectedValues = {
+  noIndex: {},
+  withConfig: {
+    ignore: ['/foo.js$/']
+  },
+  withoutConfig: {}
+};
+
+describe('readIndexConfig()', () => {
+  context('When valid config is defined', () => {
+    it('reads config object', () => {
+      const config = readIndexConfig(fixtures.withConfig);
+
+      expect(config).to.deep.equal(expectedValues.withConfig);
+    });
+  });
+
+  context('When invalid config is defined', () => {
+    it('should throw an error', () => {
+      const wrappedReadIndexConfig = () => {
+        readIndexConfig(fixtures.withInvalidConfig);
+      };
+
+      expect(wrappedReadIndexConfig).to.throw(/Configuration object must be a valid JSON./);
+    });
+  });
+
+  context('When config is NOT defined', () => {
+    it('returns an empty object', () => {
+      const config = readIndexConfig(fixtures.withoutConfig);
+
+      expect(config).to.deep.equal(expectedValues.withoutConfig);
+    });
+  });
+
+  context('When index file doesn\'t exist', () => {
+    it('returns an empty object', () => {
+      const config = readIndexConfig(fixtures.withoutConfig);
+
+      expect(config).to.deep.equal(expectedValues.noIndex);
+    });
+  });
+});

test/validateTargetDirectory.js

@@ -36,6 +36,11 @@ describe('validateTargetDirectory()', () => {
         expect(validateTargetDirectory(path.resolve(fixturesPath, 'safe-index'))).to.equal(true);
       });
     });
+    context('safe with banner', () => {
+      it('returns true', () => {
+        expect(validateTargetDirectory(path.resolve(fixturesPath, 'safe-index-with-banner'))).to.equal(true);
+      });
+    });
     context('unsafe', () => {
       it('throws an error', () => {
         expect(() => {

test/writeIndex.js

@@ -8,29 +8,51 @@ import {
 import writeIndex from '../src/utilities/writeIndex';
 import codeExample from './codeExample';
 
+const readFile = (filePath) => {
+  return fs.readFileSync(filePath, 'utf8');
+};
+
+const removeFile = (filePath) => {
+  fs.unlinkSync(filePath);
+};
+
+const appendToFile = (filePath, content) => {
+  fs.appendFileSync(filePath, content, 'utf-8');
+};
+
 const fixturesPath = path.resolve(__dirname, 'fixtures/write-index');
 
 describe('writeIndex()', () => {
   it('creates index in target directory', () => {
     const indexFilePath = path.resolve(fixturesPath, 'mixed/index.js');
 
-    try {
+    removeFile(indexFilePath);
-      fs.unlinkSync(indexFilePath);
-
-      // eslint-disable-next-line no-empty
-    } catch (error) {
-
-    }
-
     writeIndex([path.resolve(fixturesPath, 'mixed')]);
-
+    const indexCode = readFile(indexFilePath);
-    const indexCode = fs.readFileSync(indexFilePath, 'utf8');
 
     expect(indexCode).to.equal(codeExample(`
 // @create-index
 
-export bar from './bar';
+export { default as bar } from './bar';
-export foo from './foo.js';
+export { default as foo } from './foo.js';
-        `));
+    `));
+  });
+
+  it('creates index with config in target directory', () => {
+    const indexFilePath = path.resolve(fixturesPath, 'with-config/index.js');
+    // eslint-disable-next-line
+    const ignoredExportLine = `export { default as bar } from './bar.js';`;
+
+    appendToFile(indexFilePath, ignoredExportLine);
+    expect(readFile(indexFilePath).includes(ignoredExportLine)).to.equal(true);
+
+    writeIndex([path.resolve(fixturesPath, 'with-config')]);
+    const indexCode = readFile(indexFilePath);
+
+    expect(indexCode).to.equal(codeExample(`
+// @create-index {"ignore":["/bar.js$/"]}
+
+export { default as foo } from './foo.js';
+    `));
   });
 });