From 508263f5bd7094e335a460993c0a93baae732775 Mon Sep 17 00:00:00 2001
From: Tobias Koppers <tobias.koppers@googlemail.com>
Date: Fri, 6 Dec 2024 14:50:52 +0100
Subject: [PATCH] [Turbopack] add telemetry for persistent caching usage
 (#73554)

### What?

Report persistent caching as feature
---
 crates/next-api/src/project.rs                       |  4 ++++
 crates/next-core/src/next_config.rs                  | 12 ++++++++++++
 .../basic/__snapshots__/next-rs-api.test.ts.snap     |  7 +++++++
 3 files changed, 23 insertions(+)

diff --git a/crates/next-api/src/project.rs b/crates/next-api/src/project.rs
index 987bfc84bb9be3..edc1cebdfb7375 100644
--- a/crates/next-api/src/project.rs
+++ b/crates/next-api/src/project.rs
@@ -823,6 +823,10 @@ impl Project {
             "skipTrailingSlashRedirect",
             *config.skip_trailing_slash_redirect().await?,
         );
+        emit_event(
+            "persistentCaching",
+            *config.persistent_caching_enabled().await?,
+        );
 
         let config = &config.await?;
 
diff --git a/crates/next-core/src/next_config.rs b/crates/next-core/src/next_config.rs
index 951b164d9e8275..11975bc4db3526 100644
--- a/crates/next-core/src/next_config.rs
+++ b/crates/next-core/src/next_config.rs
@@ -413,6 +413,7 @@ pub struct ExperimentalTurboConfig {
     pub tree_shaking: Option<bool>,
     pub module_id_strategy: Option<ModuleIdStrategy>,
     pub minify: Option<bool>,
+    pub unstable_persistent_caching: Option<bool>,
 }
 
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, TraceRawVcs)]
@@ -1041,6 +1042,17 @@ impl NextConfig {
         Vc::cell(Some(ResolvedVc::cell(rules)))
     }
 
+    #[turbo_tasks::function]
+    pub fn persistent_caching_enabled(&self) -> Result<Vc<bool>> {
+        Ok(Vc::cell(
+            self.experimental
+                .turbo
+                .as_ref()
+                .and_then(|t| t.unstable_persistent_caching)
+                .unwrap_or_default(),
+        ))
+    }
+
     #[turbo_tasks::function]
     pub fn resolve_alias_options(&self) -> Result<Vc<ResolveAliasMap>> {
         let Some(resolve_alias) = self
diff --git a/test/development/basic/__snapshots__/next-rs-api.test.ts.snap b/test/development/basic/__snapshots__/next-rs-api.test.ts.snap
index 938bfbf52a1396..acd72d979b6ff2 100644
--- a/test/development/basic/__snapshots__/next-rs-api.test.ts.snap
+++ b/test/development/basic/__snapshots__/next-rs-api.test.ts.snap
@@ -65,6 +65,13 @@ exports[`next.rs api should detect the correct routes: diagnostics 1`] = `
       "modularizeImports": "true",
     },
   },
+  {
+    "category": "NextFeatureTelemetry_category_tbd",
+    "name": "EVENT_BUILD_FEATURE_USAGE",
+    "payload": {
+      "persistentCaching": "false",
+    },
+  },
   {
     "category": "NextFeatureTelemetry_category_tbd",
     "name": "EVENT_BUILD_FEATURE_USAGE",