fix: ficing double call for callbacks on error saving png to file

lib/renderer/png.js

@@ -58,9 +58,16 @@ exports.renderToFile = function renderToFile (path, qrData, options, cb) {
     options = undefined
   }
 
+  let called = false
+  const done = (...args) => {
+    if (called) return
+    called = true
+    cb.apply(null, args)
+  }
   const stream = fs.createWriteStream(path)
-  stream.on('error', cb)
-  stream.on('close', cb)
+
+  stream.on('error', done)
+  stream.on('close', done)
 
   exports.renderToFileStream(stream, qrData, options)
 }

lib/renderer/utils.js

@@ -39,7 +39,9 @@ exports.getOptions = function getOptions (options) {
 
   const margin = typeof options.margin === 'undefined' ||
     options.margin === null ||
-    options.margin < 0 ? 4 : options.margin
+    options.margin < 0
+    ? 4
+    : options.margin
 
   const width = options.width && options.width >= 21 ? options.width : undefined
   const scale = options.scale || 4

package.json

@@ -58,8 +58,8 @@
     "rollup-plugin-babel": "^4.4.0",
     "rollup-plugin-terser": "^5.3.0",
     "sinon": "^9.0.2",
-    "standard": "^14.3.3",
-    "tap": "^14.10.7"
+    "standard": "^16.0.4",
+    "tap": "^15.1.2"
   },
   "repository": {
     "type": "git",
@@ -71,7 +71,8 @@
   "standard": {
     "ignore": [
       "build/",
-      "examples/vendors/"
+      "examples/vendors/",
+      "lib/core/regex.js"
     ]
   }
 }

test/e2e/toFile.test.js

@@ -56,7 +56,7 @@ test('toFile png', function (t) {
     'qVO5LQqTxRrFGKNUqxRon/scYo1ijFGqVYoxRrlGKNUqxRijVKsUYp1ijFGqVYoxRrlGKN',
     'UqxRijXKP0OHEepgrecVAAAAAElFTkSuQmCC'].join('')
 
-  t.plan(9)
+  t.plan(8)
 
   QRCode.toFile(fileName, 'i am a pony!', {
     errorCorrectionLevel: 'L'

test/unit/renderer/png.test.js

@@ -92,7 +92,7 @@ test('PNG renderToFile', function (t) {
   let fsStub = sinon.stub(fs, 'createWriteStream')
   fsStub.returns(new StreamMock())
 
-  t.plan(6)
+  t.plan(5)
 
   PngRenderer.renderToFile(fileName, sampleQrData, function (err) {
     t.ok(!err,