fix: set excludeAfterRemap to false by default (#218)

Author: bahmutov

.github/ISSUE_TEMPLATE/bug_report.md

@@ -29,3 +29,6 @@ A clear and concise description of what the bug is.
 
 **Link to the repo**
 Bugs with a reproducible example, like an open source repo showing the bug, are the most likely to be resolved.
+
+**Example**
+See [#217](https://github.com/cypress-io/code-coverage/issues/217) that is an excellent bug report example

README.md

@@ -302,6 +302,8 @@ For example, if you want to only include files in the `app` folder, but exclude
 
 **Note:** if you have `all: true` NYC option set, this plugin will check the produced `.nyc_output/out.json` before generating the final report. If the `out.json` file does not have information for some files that should be there according to `include` list, then an empty placeholder will be included, see [PR 208](https://github.com/cypress-io/code-coverage/pull/208).
 
+Another important option is `excludeAfterRemap`. By default it is false, which might let excluded files through. If you are excluding the files, and the instrumenter does not respect the `nyc.exclude` setting, then add `excludeAfterRemap: true` to tell `nyc report` to exclude files. See [examples/exclude-files](examples/exclude-files).
+
 ## Disable plugin
 
 You can skip the client-side code coverage hooks by setting the environment variable `coverage` to `false`.

common-utils.js

@@ -28,7 +28,7 @@ const defaultNycOptions = {
   'report-dir': './coverage',
   reporter: ['lcov', 'clover', 'json'],
   extension: ['.js', '.cjs', '.mjs', '.ts', '.tsx', '.jsx'],
-  excludeAfterRemap: true
+  excludeAfterRemap: false
 }
 
 module.exports = {

cypress/integration/combine-spec.js

@@ -15,7 +15,7 @@ describe('Combine NYC options', () => {
       'report-dir': './coverage',
       reporter: ['lcov', 'clover', 'json'],
       extension: ['.js', '.cjs', '.mjs', '.ts', '.tsx', '.jsx'],
-      excludeAfterRemap: true
+      excludeAfterRemap: false
     })
   })
 
@@ -31,7 +31,7 @@ describe('Combine NYC options', () => {
       'report-dir': './coverage',
       reporter: ['text'],
       extension: ['.js', '.cjs', '.mjs', '.ts', '.tsx', '.jsx'],
-      excludeAfterRemap: true
+      excludeAfterRemap: false
     })
   })
 
@@ -58,7 +58,7 @@ describe('Combine NYC options', () => {
       'report-dir': './coverage',
       reporter: ['json'],
       extension: ['.js'],
-      excludeAfterRemap: true,
+      excludeAfterRemap: false,
       include: ['foo.js'],
       exclude: ['bar.js']
     })

examples/exclude-files/package.json

@@ -4,10 +4,13 @@
   "scripts": {
     "start": "../../node_modules/.bin/parcel serve index.html",
     "cy:open": "../../node_modules/.bin/cypress open",
-    "dev": "../../node_modules/.bin/start-test 1234 cy:open"
+    "cy:run": "../../node_modules/.bin/cypress run",
+    "dev": "../../node_modules/.bin/start-test 1234 cy:open",
+    "e2e": "../../node_modules/.bin/start-test 1234 cy:run"
   },
   "nyc": {
-    "exclude": ["second.js"]
+    "exclude": ["second.js"],
+    "excludeAfterRemap": true
   },
   "devDependencies": {
     "@babel/core": "7.9.0"

task.js

@@ -168,6 +168,11 @@ const tasks = {
     // https://github.com/istanbuljs/nyc#common-configuration-options
     const nycReportOptions = readNycOptions(processWorkingDirectory)
 
+    if (nycReportOptions.exclude && !Array.isArray(nycReportOptions.exclude)) {
+      console.error('NYC options: %o', nycReportOptions)
+      throw new Error('Expected "exclude" to by an array')
+    }
+
     // override a couple of options
     nycReportOptions.tempDir = coverageFolder
     if (nycReportOptions['report-dir']) {