Extract remove comments into a function

Author: mattphillips

src/index.js

@@ -1,6 +1,7 @@
 const generate = require('babel-generator').default;
 
 const looksLike = require('./utils/looks-like');
+const { removeComments } = require('./utils');
 
 module.exports = function({ template, types }) {
   return {
@@ -51,9 +52,7 @@ module.exports = function({ template, types }) {
 
         // generate the code
         const { code } = generate(body);
-
-        // remove comments
-        const normalisedCode = code.replace(/\/\/(.*)/g, '').replace(/\/\*([\s\S]*?)\*\//g, '');
+        const normalisedCode = removeComments(code);
 
         const count = (normalisedCode.match(/expect\(/g) || []).length;
         const containsExpectAssertions = normalisedCode.includes('expect.assertions(');

src/utils/index.js

@@ -0,0 +1,9 @@
+const EMPTY = '';
+const SINGLE_LINE_COMMENT = /\/\/(.*)/g;
+const MULTI_LINE_COMMENT = /\/\*([\s\S]*?)\*\//g;
+
+const removeComments = code => code.replace(SINGLE_LINE_COMMENT, EMPTY).replace(MULTI_LINE_COMMENT, EMPTY);
+
+module.exports = {
+  removeComments
+};

src/utils/index.test.js

@@ -0,0 +1,45 @@
+const { removeComments } = require('./');
+
+describe('Utils', () => {
+  describe('.removeComments', () => {
+    it('returns given string when string does not contain any comments', () => {
+      const str = 'hello world';
+      expect(removeComments(str)).toEqual(str);
+    });
+    it('returns empty string when given a single line comment', () => {
+      expect(removeComments('// hello world')).toEqual('');
+    });
+    it('returns empty string when given a multi line comment', () => {
+      expect(
+        removeComments(`/*
+        hello world
+        */`)
+      ).toEqual('');
+    });
+    it('returns string without comments when given a string containing a singleline comment', () => {
+      expect(removeComments('abc//hello world')).toEqual('abc');
+    });
+    it('returns string without comments when given a string containing a multi line comment', () => {
+      expect(
+        removeComments(`abc/*
+        hello world
+        */def`)
+      ).toEqual('abcdef');
+    });
+    it('returns string without comments when given a string with both single and multi line comments', () => {
+      expect(
+        removeComments(`abc /* hello world */
+        // foo
+        /*
+          bar
+        */
+        xyz
+        /*
+          baz
+        */
+        def // qux
+        `).replace(/\s/g, '')
+      ).toEqual('abcxyzdef');
+    });
+  });
+});