fix(ci-visibility): complete cypress instrumentation coverage

- Resolve default config file when no --config-file is passed, enabling
  plain-object configs (without defineConfig) in the standard cypress run flow
- Skip .ts config files — Cypress transpiles them internally, ESM wrapper can't
  import .ts directly
- Hook both lib/exec/{run,open}.js (Cypress 10-14) and dist/exec/{run,open}.js
  (Cypress 15+) so the CLI wrapper fires across all supported versions
- Respect configFile: false — don't override with a resolved default
- Add comments to programmatic test scripts clarifying that instrumentation
  works via the default config file, not inline configs
- Add TypeScript config regression test
- Add plain-object default config (no --config-file) regression test
- Fix ESM config imports to include .js extension for dd-trace/ci/cypress/plugin

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: juan-fernandez

.github/CODEOWNERS

@@ -125,6 +125,7 @@
 /integration-tests/cypress-plain-object-manual.config.mjs @DataDog/ci-app-libraries
 /integration-tests/cypress-return-config.config.js @DataDog/ci-app-libraries
 /integration-tests/cypress-return-config.config.mjs @DataDog/ci-app-libraries
+/integration-tests/cypress-typescript.config.ts @DataDog/ci-app-libraries
 /integration-tests/cypress.config.js @DataDog/ci-app-libraries
 /integration-tests/my-nyc.config.js @DataDog/ci-app-libraries
 /integration-tests/playwright.config.js @DataDog/ci-app-libraries

integration-tests/cypress-double-run.js

@@ -1,5 +1,9 @@
 'use strict'
 
+// Tests that cypress.run() works twice in the same process (resetRunState).
+// Instrumentation works via the default cypress.config.js in the project
+// (which uses defineConfig), NOT via the inline config below — Cypress
+// does not call setupNodeEvents from inline config objects.
 const cypress = require('cypress')
 
 const runOptions = {

integration-tests/cypress-double-run.mjs

@@ -1,3 +1,7 @@
+// Tests that cypress.run() works twice in the same process (resetRunState).
+// Instrumentation works via the default cypress.config.js in the project
+// (which uses defineConfig), NOT via the inline config below — Cypress
+// does not call setupNodeEvents from inline config objects.
 import cypress from 'cypress'
 
 const runOptions = {

integration-tests/cypress-esm-config.mjs

@@ -1,3 +1,7 @@
+// Programmatic ESM entry point for the 'esm' module type tests.
+// Instrumentation works via the default cypress.config.js in the project
+// (which uses defineConfig), NOT via the inline setupNodeEvents below —
+// Cypress does not call setupNodeEvents from inline config objects.
 import cypress from 'cypress'
 
 async function runCypress () {

integration-tests/cypress-typescript.config.ts

@@ -0,0 +1,11 @@
+import { defineConfig } from 'cypress'
+
+export default defineConfig({
+  defaultCommandTimeout: 1000,
+  e2e: {
+    specPattern: process.env.SPEC_PATTERN || 'cypress/e2e/**/*.cy.js',
+    supportFile: 'cypress/support/e2e.js',
+  },
+  video: false,
+  screenshotOnRunFailure: false,
+})

integration-tests/cypress/cypress.spec.js

@@ -404,7 +404,7 @@ moduleTypes.forEach(({
       assert.strictEqual(exitCode, 0, `cypress process should exit successfully\n${testOutput}`)
     })
 
-    over10It('reports tests when cypress.run is called twice in the same process', async () => {
+    over10It('reports tests when cypress.run is called twice (multi-run state reset)', async () => {
       const receiverPromise = receiver
         .gatherPayloadsMaxTimeout(({ url }) => url.endsWith('/api/v2/citestcycle'), (payloads) => {
           const passedTests = payloads
@@ -543,6 +543,101 @@ moduleTypes.forEach(({
       }
     )
 
+    over10It(
+      'auto-instruments a plain-object default config (no --config-file)',
+      async () => {
+        const originalConfig = path.join(cwd, 'cypress.config.js')
+        const backupConfig = path.join(cwd, 'cypress.config.js.bak')
+        const plainObjectConfig = path.join(cwd, 'cypress-plain-object-auto.config.js')
+
+        // Replace default cypress.config.js with the plain-object config
+        fs.renameSync(originalConfig, backupConfig)
+        fs.copyFileSync(plainObjectConfig, originalConfig)
+
+        try {
+          const receiverPromise = receiver
+            .gatherPayloadsMaxTimeout(({ url }) => url.endsWith('/api/v2/citestcycle'), (payloads) => {
+              const events = payloads
+                .flatMap(({ payload }) => payload.events)
+                .filter(event => event.type === 'test')
+              const passedTest = events.find(event =>
+                event.content.resource === 'cypress/e2e/basic-pass.js.basic pass suite can pass'
+              )
+
+              assertObjectContains(passedTest?.content, {
+                meta: {
+                  [TEST_STATUS]: 'pass',
+                  [TEST_FRAMEWORK]: 'cypress',
+                },
+              })
+            }, 20000)
+
+          const envVars = getCiVisAgentlessConfig(receiver.port)
+
+          childProcess = exec(
+            './node_modules/.bin/cypress run',
+            {
+              cwd,
+              env: {
+                ...envVars,
+                CYPRESS_BASE_URL: `http://localhost:${webAppPort}`,
+                SPEC_PATTERN: 'cypress/e2e/basic-pass.js',
+              },
+            }
+          )
+
+          const [[exitCode]] = await Promise.all([
+            once(childProcess, 'exit'),
+            receiverPromise,
+          ])
+
+          assert.strictEqual(exitCode, 0, 'cypress process should exit successfully')
+        } finally {
+          fs.renameSync(backupConfig, originalConfig)
+        }
+      }
+    )
+
+    over10It('reports tests with a TypeScript config file', async () => {
+      const receiverPromise = receiver
+        .gatherPayloadsMaxTimeout(({ url }) => url.endsWith('/api/v2/citestcycle'), (payloads) => {
+          const events = payloads
+            .flatMap(({ payload }) => payload.events)
+            .filter(event => event.type === 'test')
+          const passedTest = events.find(event =>
+            event.content.resource === 'cypress/e2e/basic-pass.js.basic pass suite can pass'
+          )
+
+          assertObjectContains(passedTest?.content, {
+            meta: {
+              [TEST_STATUS]: 'pass',
+              [TEST_FRAMEWORK]: 'cypress',
+            },
+          })
+        }, 20000)
+
+      const envVars = getCiVisAgentlessConfig(receiver.port)
+
+      childProcess = exec(
+        './node_modules/.bin/cypress run --config-file cypress-typescript.config.ts',
+        {
+          cwd,
+          env: {
+            ...envVars,
+            CYPRESS_BASE_URL: `http://localhost:${webAppPort}`,
+            SPEC_PATTERN: 'cypress/e2e/basic-pass.js',
+          },
+        }
+      )
+
+      const [[exitCode]] = await Promise.all([
+        once(childProcess, 'exit'),
+        receiverPromise,
+      ])
+
+      assert.strictEqual(exitCode, 0, 'cypress process should exit successfully')
+    })
+
     over10It('does not modify the user support file and cleans up the injected wrapper', async () => {
       const supportFilePath = path.join(cwd, 'cypress/support/e2e.js')
       const originalSupportContent = fs.readFileSync(supportFilePath, 'utf8')

packages/datadog-instrumentations/src/cypress-config.js

@@ -270,14 +270,33 @@ function createConfigWrapper (originalConfigFile) {
 function wrapCliConfigFileOptions (options) {
   const noop = { options, cleanup: () => {} }
 
-  if (!options || typeof options.configFile !== 'string') return noop
+  if (!options) return noop
 
   const projectRoot = typeof options.project === 'string' ? options.project : process.cwd()
-  const configFilePath = path.isAbsolute(options.configFile)
-    ? options.configFile
-    : path.resolve(projectRoot, options.configFile)
+  let configFilePath
+
+  if (options.configFile === false) {
+    // configFile: false means "no config file" — respect Cypress's semantics
+    return noop
+  } else if (typeof options.configFile === 'string') {
+    configFilePath = path.isAbsolute(options.configFile)
+      ? options.configFile
+      : path.resolve(projectRoot, options.configFile)
+  } else {
+    // No explicit --config-file: resolve the default cypress.config.{js,ts,cjs,mjs}
+    for (const ext of ['.js', '.ts', '.cjs', '.mjs']) {
+      const candidate = path.join(projectRoot, `cypress.config${ext}`)
+      if (fs.existsSync(candidate)) {
+        configFilePath = candidate
+        break
+      }
+    }
+  }
 
-  if (!fs.existsSync(configFilePath)) return noop
+  // Skip .ts files — Cypress transpiles them internally via its own loader.
+  // The ESM wrapper can't import .ts directly. The defineConfig shimmer
+  // handles .ts configs since they're transpiled to CJS by Cypress.
+  if (!configFilePath || !fs.existsSync(configFilePath) || path.extname(configFilePath) === '.ts') return noop
 
   const wrapperFile = createConfigWrapper(configFilePath)