feat: allow usage of ignoreClassMethods from istanbul (#785)

Author: katerberg

README.md

@@ -272,6 +272,7 @@ Any configuration options that can be set via the command line can also be speci
     "exclude": [
       "src/**/*.spec.js"
     ],
+    "ignore-class-method": "methodToIgnore",
     "reporter": [
       "lcov",
       "text-summary"
@@ -344,6 +345,19 @@ hints:
 * `/* istanbul ignore file */`: ignore an entire source-file (this should be
   placed at the top of the file).
 
+## Ignoring Methods
+
+There may be some methods that you want to universally ignore out of your classes
+rather than having to ignore every instance of that method:
+
+```json
+{
+  "nyc": {
+    "ignore-class-method": "render"
+  }
+}
+```
+
 ## Integrating with coveralls
 
 [coveralls.io](https://coveralls.io) is a great tool for adding

index.js

@@ -136,6 +136,7 @@ NYC.prototype.instrumenter = function () {
 
 NYC.prototype._createInstrumenter = function () {
   return this._instrumenterLib(this.cwd, {
+    ignoreClassMethods: [].concat(this.config.ignoreClassMethod).filter(a => a),
     produceSourceMap: this.config.produceSourceMap,
     compact: this.config.compact,
     preserveComments: this.config.preserveComments

lib/instrumenters/istanbul.js

@@ -12,6 +12,7 @@ function InstrumenterIstanbul (cwd, options) {
     compact: options.compact,
     preserveComments: options.preserveComments,
     produceSourceMap: options.produceSourceMap,
+    ignoreClassMethods: options.ignoreClassMethods,
     esModules: true
   })
 

package.json

@@ -85,7 +85,7 @@
     "glob": "^7.0.6",
     "istanbul-lib-coverage": "^1.1.2",
     "istanbul-lib-hook": "^1.1.0",
-    "istanbul-lib-instrument": "^1.9.2",
+    "istanbul-lib-instrument": "^1.10.0",
     "istanbul-lib-report": "^1.1.3",
     "istanbul-lib-source-maps": "^1.2.3",
     "istanbul-reports": "^1.1.4",

test/fixtures/cli/classes.js

@@ -0,0 +1,15 @@
+'use strict'
+
+class Funclass {
+  hit() {
+    const miss = () => {
+      console.log('This is intentionally uncovered');
+    }
+  }
+
+  skip() {
+    console.log('this will be skipped');
+  }
+}
+
+new Funclass().hit();

test/nyc-bin.js

@@ -71,6 +71,29 @@ describe('the nyc cli', function () {
     })
   })
 
+  describe('--ignore-class-method', function () {
+    it('skips methods that match ignored name but still catches those that are not', function (done) {
+      var args = [bin, '--all', '--ignore-class-method', 'skip', process.execPath, './classes.js']
+
+      var proc = spawn(process.execPath, args, {
+        cwd: fixturesCLI,
+        env: env
+      })
+
+      var stdout = ''
+      proc.stdout.on('data', function (chunk) {
+        stdout += chunk
+      })
+
+      proc.on('close', function (code) {
+        code.should.equal(0)
+        var classesOutput = (stdout.match(/^(.*classes\.js).*$/m) || ['no result found'])[0]
+        classesOutput.should.match(/6 \|/)
+        done()
+      })
+    })
+  })
+
   describe('--check-coverage', function () {
     it('fails when the expected coverage is below a threshold', function (done) {
       var args = [bin, '--check-coverage', '--lines', '51', process.execPath, './half-covered.js']
@@ -379,7 +402,6 @@ describe('the nyc cli', function () {
   })
 
   describe('coverage', function () {
-    if (parseInt(process.versions.node.split('.')[0]) < 4) return
     it('reports appropriate coverage information for es6 source files', function (done) {
       var args = [bin, '--reporter=lcov', '--reporter=text', process.execPath, './es6.js']