feat: add ignore option (fix #31) (#37)

- Add functionality to ignore files based on provided
regular expressions
- Support writeIndex and writeIndexCli
- in index.js config must be specified as below

    // @create-index {"ignore":["/foo.js"]}

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']);
@@ -21,7 +21,7 @@ describe('createIndexCode()', () => {
 // @create-index
 
 export { default as foo } from './foo';
-        `));
+    `));
   });
   it('describes multiple children', () => {
     const indexCode = createIndexCode(['bar', 'foo']);
@@ -31,7 +31,7 @@ export { default as foo } from './foo';
 
 export { default as bar } from './bar';
 export { default as foo } from './foo';
-        `));
+    `));
   });
   context('file with extension', () => {
     it('removes the extension from the export statement', () => {
@@ -41,7 +41,7 @@ export { default as foo } from './foo';
 // @create-index
 
 export { default as foo } from './foo.js';
-            `));
+      `));
     });
   });
   context('multiple, unsorted', () => {
@@ -53,7 +53,23 @@ export { default as foo } from './foo.js';
 
 export { default as bar } from './bar';
 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/write-index/with-config/index.js

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

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/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 {
-      fs.unlinkSync(indexFilePath);
-
-      // eslint-disable-next-line no-empty
-    } catch (error) {
-
-    }
-
+    removeFile(indexFilePath);
     writeIndex([path.resolve(fixturesPath, 'mixed')]);
-
-    const indexCode = fs.readFileSync(indexFilePath, 'utf8');
+    const indexCode = readFile(indexFilePath);
 
     expect(indexCode).to.equal(codeExample(`
 // @create-index
 
 export { default as bar } from './bar';
 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';
+    `));
   });
 });