fix(plugin-coverage): skip lcov reporter validation if jest config uses preset

reporter could be configured in preset

fix #727

Author: matejchalk

packages/plugin-coverage/src/lib/nx/coverage-paths.ts

@@ -165,24 +165,22 @@ export async function getCoveragePathForJest(
 ) {
   const { jestConfig } = options;
 
-  const { coverageDirectory, coverageReporters } =
-    options.coverageDirectory && options.coverageReporters
-      ? options // skip import if both overrides available
-      : {
-          ...(await importEsmModule<JestCoverageConfig>({
-            filepath: jestConfig,
-            format: 'cjs',
-          })),
-          ...options,
-        };
+  const testConfig = await importEsmModule<JestCoverageConfig>({
+    filepath: jestConfig,
+    format: 'cjs',
+  });
+  const { coverageDirectory, coverageReporters } = {
+    ...testConfig,
+    ...options,
+  };
 
   if (coverageDirectory == null) {
     throw new Error(
       `Jest coverage configuration at ${jestConfig} does not include coverage path for target ${target} in ${project.name}. Add the path under coverageDirectory.`,
     );
   }
 
-  if (!coverageReporters?.includes('lcov')) {
+  if (!coverageReporters?.includes('lcov') && !('preset' in testConfig)) {
     throw new Error(
       `Jest coverage configuration at ${jestConfig} does not include LCOV report format for target ${target} in ${project.name}. Add 'lcov' format under coverageReporters.`,
     );

packages/plugin-coverage/src/lib/nx/coverage-paths.unit.test.ts

@@ -51,6 +51,11 @@ vi.mock('bundle-require', () => ({
       coverageDirectory: 'coverage',
     };
 
+    const JEST_PRESET: JestCoverageConfig & { preset?: string } = {
+      preset: '../../jest.preset.ts',
+      coverageDirectory: 'coverage',
+    };
+
     const wrapReturnValue = (
       value: VitestCoverageConfig | JestCoverageConfig,
     ) => ({ mod: { default: value } });
@@ -69,6 +74,8 @@ vi.mock('bundle-require', () => ({
         return wrapReturnValue(JEST_NO_LCOV);
       case 'jest-no-dir':
         return wrapReturnValue(JEST_NO_DIR);
+      case 'jest-preset':
+        return wrapReturnValue(JEST_PRESET);
       default:
         return wrapReturnValue({});
     }
@@ -327,6 +334,29 @@ describe('getCoveragePathForJest', () => {
     ).rejects.toThrow(/configuration .* does not include LCOV report format/);
   });
 
+  it('should not throw if lcov reporter in both project.json and jest config', async () => {
+    await expect(
+      getCoveragePathForJest(
+        {
+          jestConfig: 'jest-valid.config.integration.ts',
+          coverageReporters: ['lcov'],
+        },
+        { name: 'core', root: join('packages', 'core') },
+        'integration-test',
+      ),
+    ).resolves.toBeTypeOf('string');
+  });
+
+  it('should not throw regarding missing lcov reporter if jest config uses preset', async () => {
+    await expect(
+      getCoveragePathForJest(
+        { jestConfig: 'jest-preset.config.ts' },
+        { name: 'core', root: join('packages', 'core') },
+        'test',
+      ),
+    ).resolves.toBeTypeOf('string');
+  });
+
   it('should handle absolute path in coverageDirectory', async () => {
     await expect(
       getCoveragePathForJest(