chore: test that coverageMap exists, add docs about coverageMap

Author: sheremet-va

docs/guide/reporters.md

@@ -263,7 +263,7 @@ export default defineConfig({
 
 ### JSON Reporter
 
-Outputs a report of the test results in JSON format. Can either be printed to the terminal or written to a file using the [`outputFile`](/config/#outputfile) configuration option.
+Generates a report of the test results in a JSON format compatible with Jest's `--json` option. Can either be printed to the terminal or written to a file using the [`outputFile`](/config/#outputfile) configuration option.
 
 :::code-group
 ```bash [CLI]
@@ -322,10 +322,15 @@ Example of a JSON report:
       "message": "",
       "name": "/root-directory/__tests__/test-file-1.test.ts"
     }
-  ]
+  ],
+  "coverageMap": {}
 }
 ```
 
+::: info
+Since Vitest 2.2, the JSON reporter includes coverage information in `coverageMap` if coverage is enabled.
+:::
+
 ### HTML Reporter
 
 Generates an HTML file to view test results through an interactive [GUI](/guide/ui). After the file has been generated, Vitest will keep a local development server running and provide a link to view the report in a browser.

test/workspaces/globalTest.ts

@@ -37,6 +37,7 @@ export async function teardown() {
     assert.equal(results.numTotalTestSuites, 28)
     assert.equal(results.numTotalTests, 31)
     assert.equal(results.numPassedTests, 31)
+    assert.ok(results.coverageMap)
 
     const shared = results.testResults.filter((r: any) => r.name.includes('space_shared/test.spec.ts'))