fix(pnpr): print the S3 key prefix in config check without debug formatting (#17416)

The storage summary formatted `Option<String>` with `{:?}`, so it showed
`prefix: Some("pnpr")` or `prefix: None`. It now prints the normalized
prefix the store uses for its keys, and nothing when there is none. The
custom object store line gets the same treatment.

.changeset/config-check-s3-prefix.md

@@ -0,0 +1,5 @@
+---
+"@pnpm/pnpr": patch
+---
+
+`pnpr config check` now prints the S3 key prefix as plain text, such as `prefix: pnpr/`, and leaves it out when none is set. It printed `prefix: Some("pnpr")` or `prefix: None`.

pnpr/crates/pnpr/src/config_check.rs

@@ -1,6 +1,7 @@
 use miette::IntoDiagnostic as _;
 use pnpr_config::{
     BackendConfig, Config, ConfigSource, FeatureOverrides, HostedStoreConfig, MaxUsers,
+    normalize_key_prefix,
 };
 use pnpr_package_name::Ecosystem;
 use pnpr_registry::{Registries, Registry};
@@ -142,11 +143,17 @@ fn describe_storage_backend(config: &Config) -> String {
             let display_path = config.storage.hosted_dir.display();
             format!("local filesystem ({display_path})")
         }
-        HostedStoreConfig::S3(settings) => {
-            format!("S3 (bucket: {}, prefix: {:?})", settings.bucket, settings.prefix)
-        }
+        HostedStoreConfig::S3(settings) => match settings.normalized_prefix().as_str() {
+            "" => format!("S3 (bucket: {})", settings.bucket),
+            prefix => {
+                format!("S3 (bucket: {}, prefix: {})", settings.bucket, prefix.escape_debug())
+            }
+        },
         HostedStoreConfig::ObjectStore { prefix, .. } => {
-            format!("custom object store (prefix: {prefix:?})")
+            match normalize_key_prefix(Some(prefix)).as_str() {
+                "" => "custom object store".to_string(),
+                prefix => format!("custom object store (prefix: {})", prefix.escape_debug()),
+            }
         }
     }
 }

pnpr/crates/pnpr/tests/tooling.rs

@@ -513,6 +513,43 @@ defaultRegistry:
     assert!(output.contains("Default registries: npm=local, cargo=crates"), "{output}");
 }
 
+#[test]
+fn test_config_check_reports_the_s3_key_prefix() {
+    let dir = TempDir::new().unwrap();
+    let report = |prefix: &str| {
+        let yaml = format!(
+            r"
+storage: '{}'
+cache: '{}'
+s3:
+  bucket: packages
+  region: auto
+  endpoint: https://storage.example.com
+{prefix}
+registries:
+  local:
+    type: hosted
+    packages:
+      '@acme/*':
+        publish: $authenticated
+",
+            dir.path().join("hosted").display(),
+            dir.path().join("cache").display(),
+        );
+        let config_file = dir.path().join("pnpr.yaml");
+        std::fs::write(&config_file, yaml).unwrap();
+        let report = pnpr::config_check::check_config(Some(&config_file)).unwrap();
+        pnpr::config_check::format_report(&report)
+    };
+
+    let output = report("  prefix: /pnpr");
+    assert!(output.contains("Storage: S3 (bucket: packages, prefix: pnpr/)\n"), "{output}");
+    let output = report("");
+    assert!(output.contains("Storage: S3 (bucket: packages)\n"), "{output}");
+    let output = report(r#"  prefix: "pn\npr""#);
+    assert!(output.contains(r"Storage: S3 (bucket: packages, prefix: pn\npr/)"), "{output}");
+}
+
 #[test]
 fn test_config_check_hides_an_unparsable_database_url() {
     let dir = TempDir::new().unwrap();