add new testing page

Author: devalog

fern/docs.yml

@@ -196,6 +196,9 @@ redirects:
   - source: /learn/sdks/capabilities/idempotency-headers
     destination: /learn/sdks/deep-dives/idempotency
     permanent: true
+  - source: /learn/sdks/capabilities/integration-tests
+    destination: /learn/sdks/deep-dives/testing
+    permanent: true
 
   # SDK Package Managers redirects
   - source: /learn/sdks/package-managers/:slug*

fern/products/sdks/capabilities.mdx

@@ -60,8 +60,8 @@ layout: overview
   <Card title="Server-Sent Events" icon="fa-duotone fa-broadcast-tower">
     Stream JSON data from your server to your client (i.e. chat completions)
   </Card>
-  <Card title="Integration Tests" icon="fa-duotone fa-flask">
-    Test your SDK against a mock server
+  <Card title="Testing" icon="fa-duotone fa-flask" href="/sdks/deep-dives/testing">
+    Auto-generated and handwritten tests to ensure your SDK works in production
   </Card>
   <Card title="Code Snippets" icon="fa-duotone fa-brackets-curly">
     No longer depend on manually written code snippets

fern/products/sdks/guides/testing.mdx

@@ -0,0 +1,33 @@
+---
+title: Testing
+description: Fern automatically generates unit tests and mock server tests for SDKs to ensure quality before release
+---
+
+Fern provides comprehensive testing for your SDKs through generated and handwritten tests.
+
+## Generated tests
+
+<Markdown src="/snippets/pro-plan.mdx"/>
+
+Fern auto-generates tests that must pass before SDK release. Fern generates a GitHub workflow in each SDK repository that runs unit and mock server tests on every pull request, commit, and release.
+
+
+### Unit tests
+
+Fern generates unit tests for all SDK languages. They verify individual methods in isolation without making network calls.
+
+### Mock server tests
+
+Mock server (wire) tests run your SDK against a mock server generated from your API definition. They validate serialization, endpoints, headers, and status code handling. 
+
+Mock server tests are available for TypeScript, Go, and Java. 
+
+## Integration tests
+
+<Markdown src="/snippets/enterprise-plan.mdx"/>
+
+Handwritten integration tests run against your real API server to test end-to-end functionality with live data.
+
+## Adding additional tests
+
+You can add custom tests directly to your SDK repositories. Include test files in your `.fernignore` file to prevent overwrites during regeneration.

fern/products/sdks/sdks.yml

@@ -234,6 +234,8 @@ navigation:
       - page: Self-hosted SDKs
         path: ./guides/self-hosted.mdx
         slug: self-hosted
+      - page: Testing
+        path: ./guides/testing.mdx
   - section: Reference
     contents: 
       - page: generators.yml