fix: JSON being output was not valid

👍 thanks for the fix @SanterreJo.

lib/puppeteer-to-istanbul.js

@@ -25,7 +25,7 @@ class PuppeteerToIstanbul {
     const fd = fs.openSync(outFilePath, 'a')
     fs.writeSync(fd, '{')
 
-    this.puppeteerToV8Info.forEach(jsFile => {
+    this.puppeteerToV8Info.forEach((jsFile, index) => {
       const script = v8toIstanbul(jsFile.url)
       script.applyCoverage(jsFile.functions)
 
@@ -39,7 +39,9 @@ class PuppeteerToIstanbul {
       let jsonStr = JSON.stringify(jsonPart)
         .replace(/^{/, '')
         .replace(/}$/, '')
-      fs.writeSync(fd, jsonStr)
+
+      const isLastIteration = index === (this.puppeteerToV8Info.length - 1)
+      fs.writeSync(fd, jsonStr + (isLastIteration ? '' : ','))
     })
 
     fs.writeSync(fd, '}')

package.json

@@ -30,6 +30,7 @@
     "mocha": "^5.0.1",
     "nyc": "^11.4.1",
     "puppeteer": "^1.1.1",
+    "rimraf": "^3.0.0",
     "standard": "^11.0.0",
     "standard-version": "^4.3.0"
   },

test/puppeteer-to-istanbul.js

@@ -1,19 +1,25 @@
-// /* globals describe, it, before */
-
-// var PuppeteerToIstanbul = require('../lib/puppeteer-to-istanbul')()
-
-// require('chai').should()
-
-// describe('puppeteer-to-istanbul', () => {
-
-//   const fixture = require('./fixtures/function-coverage-missing.json')
-
-//   before(() => {
-
-//   })
-
-//   it('translates ranges into lines for istanbul', () => {
-
-//   })
-
-// })
+/* globals describe, it */
+
+const should = require('chai').should()
+const fs = require('fs')
+
+var PuppeteerToIstanbul = require('../lib/puppeteer-to-istanbul')
+
+describe('puppeteer-to-istanbul', () => {
+  it('outputs a valid out.json file', () => {
+    const fixture = require('./fixtures/two-inline.json')
+    const pti = PuppeteerToIstanbul(fixture)
+    pti.writeIstanbulFormat()
+    const content = fs.readFileSync('.nyc_output/out.json', 'utf8')
+    const jsonObject = JSON.parse(content)
+    should.exist(jsonObject)
+    fs.unlinkSync('.nyc_output/out.json')
+  })
+
+  it('correctly sets coverage info', () => {
+    const fixture = require('./fixtures/two-inline.json')
+    const pti = PuppeteerToIstanbul(fixture)
+    pti.setCoverageInfo(fixture)
+    pti.coverageInfo.should.eql(fixture)
+  })
+})