feat(@angular/cli): allow code coverage excludes (#4966)

A new CLI config entry under `test` allows you to list exclude globs for code coverage:

```
  "test": {
    "codeCoverage": {
      "exclude": [
        "src/polyfills.ts",
        "**/test.ts"
      ]
    },
    "karma": {
      "config": "./karma.conf.js"
    }
  },
```

packages/@angular/cli/lib/config/schema.json

@@ -32,7 +32,7 @@
           "name": {
             "type": "string",
             "description": "Name of the app."
-          },          
+          },
           "root": {
             "type": "string",
             "description": "The root directory of the app."
@@ -270,6 +270,20 @@
             }
           },
           "additionalProperties": false
+        },
+        "codeCoverage": {
+          "type": "object",
+          "properties": {
+            "exclude": {
+              "description": "Globs to exclude from code coverage.",
+              "type": "array",
+              "items": {
+                "type": "string"
+              },
+              "default": []
+            }
+          },
+          "additionalProperties": false
         }
       },
       "additionalProperties": false
@@ -435,19 +449,19 @@
               "description": "The host the application will be served on",
               "type": "string",
               "default": "localhost"
-            
+
             },
             "ssl": {
               "description": "Enables ssl for the application",
               "type": "boolean",
               "default": false
-            
+
             },
             "sslKey": {
               "description": "The ssl key used by the server",
               "type": "string",
               "default": "ssl/server.key"
-            
+
             },
             "sslCert": {
               "description": "The ssl certificate used by the server",

packages/@angular/cli/models/webpack-configs/test.ts

@@ -1,4 +1,5 @@
 import * as path from 'path';
+import * as glob from 'glob';
 import * as webpack from 'webpack';
 
 import { CliConfig } from '../config';
@@ -20,14 +21,27 @@ export function getTestConfig(testConfig: WebpackTestOptions) {
   const appConfig = CliConfig.fromProject().config.apps[0];
   const extraRules: any[] = [];
 
-  if (testConfig.codeCoverage) {
+  if (testConfig.codeCoverage && CliConfig.fromProject()) {
+    const codeCoverageExclude = CliConfig.fromProject().get('test.codeCoverage.exclude');
+    let exclude: (string | RegExp)[] = [
+      /\.(e2e|spec)\.ts$/,
+      /node_modules/
+    ];
+
+    if (codeCoverageExclude) {
+      codeCoverageExclude.forEach((excludeGlob: string) => {
+        const excludeFiles = glob
+          .sync(path.join(projectRoot, excludeGlob), { nodir: true })
+          .map(file => path.normalize(file));
+        exclude.push(...excludeFiles);
+      });
+    }
+
+
     extraRules.push({
       test: /\.(js|ts)$/, loader: 'istanbul-instrumenter-loader',
       enforce: 'post',
-      exclude: [
-        /\.(e2e|spec)\.ts$/,
-        /node_modules/
-      ]
+      exclude
     });
   }
 

tests/e2e/tests/misc/coverage.ts

@@ -1,9 +1,26 @@
-import {expectFileToExist} from '../../utils/fs';
+import {expectFileToExist, expectFileToMatch} from '../../utils/fs';
+import {updateJsonFile} from '../../utils/project';
+import {expectToFail} from '../../utils/utils';
 import {ng} from '../../utils/process';
 
 
-export default function() {
+export default function () {
   return ng('test', '--single-run', '--code-coverage')
     .then(() => expectFileToExist('coverage/src/app'))
-    .then(() => expectFileToExist('coverage/lcov.info'));
+    .then(() => expectFileToExist('coverage/lcov.info'))
+    // Verify code coverage exclude work
+    .then(() => expectFileToMatch('coverage/lcov.info', 'polyfills.ts'))
+    .then(() => expectFileToMatch('coverage/lcov.info', 'test.ts'))
+    .then(() => updateJsonFile('.angular-cli.json', configJson => {
+      const test = configJson['test'];
+      test['codeCoverage'] = {
+        exclude: [
+          'src/polyfills.ts',
+          '**/test.ts'
+        ]
+      };
+    }))
+    .then(() => ng('test', '--single-run', '--code-coverage'))
+    .then(() => expectToFail(() => expectFileToMatch('coverage/lcov.info', 'polyfills.ts')))
+    .then(() => expectToFail(() => expectFileToMatch('coverage/lcov.info', 'test.ts')));
 }