feat: add --extension option (#331)

Author: DylanPiercey

README.md

@@ -35,7 +35,8 @@ Here is a list of common options. Run `c8 --help` for the full list and document
 | `--all` | see [section below](#checking-for-full-source-coverage-using---all) for more info | `boolean` | `false` |
 | `--src` | see [section below](#checking-for-full-source-coverage-using---all) for more info | `Array<string>` | `[process.cwd()]`|
 | `-n`, `--include` | see [section below](#checking-for-full-source-coverage-using---all) for more info | `Array<string>` | `[]` (include all files) |
-| `-x`, `--exclude` | see [section below](#checking-for-full-source-coverage-using---all) for more info | `Array<string>` | [list](https://github.com/istanbuljs/schema/blob/main/default-exclude.js) |
+| `-x`, `--exclude` | see [section below](#checking-for-full-source-coverage-using---all) for more info | `Array<string>` | [list](https://github.com/istanbuljs/schema/blob/master/default-exclude.js) |
+| `-e`, `--extension` | only files matching these extensions will show coverage | `string | Array<string>` | [list](https://github.com/istanbuljs/schema/blob/master/default-extension.js) |
 | `--skip-full` | do not show files with 100% statement, branch, and function coverage | `boolean` | `false` |
 | `--check-coverage` | check whether coverage is within thresholds provided | `boolean` | `false` |
 | `--temp-directory` | directory V8 coverage data is written to and read from | `string` | `process.env.NODE_V8_COVERAGE` |

index.d.ts

@@ -3,6 +3,7 @@ export type Watermark = [number, number];
 export declare class Report {
     constructor(opts: {
         exclude?: string | string[],
+        extension?: string | string[],
         excludeAfterRemap?: boolean,
         include?: string | string[],
         reporter: string[],

lib/commands/check-coverage.js

@@ -22,6 +22,7 @@ exports.handler = function (argv) {
   const report = Report({
     include: argv.include,
     exclude: argv.exclude,
+    extension: argv.extension,
     reporter: Array.isArray(argv.reporter) ? argv.reporter : [argv.reporter],
     reportsDirectory: argv['reports-dir'],
     tempDirectory: argv.tempDirectory,

lib/commands/report.js

@@ -21,6 +21,7 @@ exports.outputReport = async function (argv) {
   const report = Report({
     include: argv.include,
     exclude: argv.exclude,
+    extension: argv.extension,
     excludeAfterRemap: argv.excludeAfterRemap,
     reporter: Array.isArray(argv.reporter) ? argv.reporter : [argv.reporter],
     reportsDirectory: argv['reports-dir'],

lib/parse-args.js

@@ -1,4 +1,5 @@
 const defaultExclude = require('@istanbuljs/schema/default-exclude')
+const defaultExtension = require('@istanbuljs/schema/default-extension')
 const findUp = require('find-up')
 const { readFileSync } = require('fs')
 const Yargs = require('yargs/yargs')
@@ -58,6 +59,12 @@ function buildYargs (withCommands = false) {
       group: 'Reporting options',
       describe: 'a list of specific files and directories that should be excluded from coverage (glob patterns are supported)'
     })
+    .option('extension', {
+      alias: 'e',
+      default: defaultExtension,
+      group: 'Reporting options',
+      describe: 'a list of specific file extensions that should be covered'
+    })
     .option('exclude-after-remap', {
       alias: 'a',
       type: 'boolean',

lib/report.js

@@ -15,6 +15,7 @@ const debuglog = util.debuglog('c8')
 class Report {
   constructor ({
     exclude,
+    extension,
     excludeAfterRemap,
     include,
     reporter,
@@ -38,6 +39,7 @@ class Report {
     this.exclude = new Exclude({
       exclude: exclude,
       include: include,
+      extension: extension,
       relativePath: !allowExternal,
       excludeNodeModules: excludeNodeModules
     })

package-lock.json

@@ -0,0 +1,24 @@
+require('./async')
+
+console.info('i am a line of code')
+
+function apple (awesome) {
+  if (false || true) {
+    console.info('what')
+  }
+  if (true || false) {
+    console.log('hey')
+  }
+}
+
+function missed () {
+  
+}
+
+function missed2 () {
+  
+}
+
+apple()
+apple()
+apple()

test/fixtures/custom-ext.special

@@ -630,4 +630,20 @@ describe('c8', () => {
       output.toString('utf8').should.matchSnapshot()
     })
   })
+
+  describe('--extension', () => {
+    it('includes coverage when extensions specified', () => {
+      const { output } = spawnSync(nodePath, [
+        c8Path,
+        '--exclude="test/*.js"',
+        '--extension=.js',
+        '--extension=.special',
+        '--temp-directory=tmp/extension',
+        '--clean=false',
+        nodePath,
+        require.resolve('./fixtures/custom-ext.special')
+      ])
+      output.toString('utf8').should.matchSnapshot()
+    })
+  })
 })

test/integration.js

@@ -125,6 +125,25 @@ All files    |     100 |      100 |     100 |     100 |
 ,"
 `;
 
+exports[`c8 --extension includes coverage when extensions specified 1`] = `
+",hey
+i am a line of code
+what
+hey
+what
+hey
+what
+hey
+--------------------|---------|----------|---------|---------|-------------------
+File                | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
+--------------------|---------|----------|---------|---------|-------------------
+All files           |   83.33 |    85.71 |      60 |   83.33 |                   
+ async.js           |     100 |      100 |     100 |     100 |                   
+ custom-ext.special |      75 |    66.66 |   33.33 |      75 | 14-16,18-20       
+--------------------|---------|----------|---------|---------|-------------------
+,"
+`;
+
 exports[`c8 ESM Modules collects coverage for ESM modules 1`] = `
 ",bar foo
 ------------|---------|----------|---------|---------|-------------------