Allow existing GPG keys with cloned stores

crates/storage/src/mobile_key_transfer.rs

@@ -145,7 +145,7 @@ pub struct MobileKeyTransferService {
 impl MobileKeyTransferService {
     pub fn load() -> Result<Self, MobileKeyTransferError> {
         let config = Config::load(None)?;
-        let keys = KeyStore::load(config.key_material())?;
+        let keys = load_keys_or_empty(config.key_material())?;
         Ok(Self { config, keys })
     }
 
@@ -316,16 +316,24 @@ impl MobileKeyTransferImport {
         }
 
         if matches!(self.destination, MobileKeyTransferDestination::LocalSetup) {
-            if key.kind != MobileKeyTransferKind::Private || !make_default {
+            if key.kind != MobileKeyTransferKind::Private {
                 return Err(MobileKeyTransferError::PublicDefault);
             }
-            let outcome = crate::mobile_onboarding::MobileOnboardingOperation::default()
-                .setup_local_imported(
+            let operation = crate::mobile_onboarding::MobileOnboardingOperation::default();
+            let outcome = if make_default {
+                operation.setup_local_imported(
                     SecretBytes::new(armor.expose().to_vec()),
                     passphrase,
                     overwrite,
                 )
-                .map_err(MobileKeyTransferError::LocalSetup)?;
+            } else {
+                operation.stage_local_imported(
+                    SecretBytes::new(armor.expose().to_vec()),
+                    passphrase,
+                    overwrite,
+                )
+            }
+            .map_err(MobileKeyTransferError::LocalSetup)?;
             return Ok(MobileKeyTransferOutcome {
                 title: outcome.title().to_owned(),
                 detail: outcome.detail().to_owned(),
@@ -334,7 +342,7 @@ impl MobileKeyTransferImport {
         let MobileKeyTransferDestination::Configured(config) = &self.destination else {
             unreachable!("local setup returned above")
         };
-        let existing = KeyStore::load(config.key_material())?;
+        let existing = load_keys_or_empty(config.key_material())?;
         if let Some(found) = existing
             .infos()
             .find(|info| info.fingerprint().as_str() == key.fingerprint)
@@ -389,6 +397,13 @@ impl MobileKeyTransferImport {
     }
 }
 
+fn load_keys_or_empty(path: &Path) -> Result<KeyStore, CryptoError> {
+    match KeyStore::load(path) {
+        Err(CryptoError::NoKeyMaterial) => Ok(KeyStore::new()),
+        result => result,
+    }
+}
+
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub enum MobileKeyTransferError {
     Configuration,
@@ -640,7 +655,7 @@ fn set_private_permissions(_temporary: &TempFile<'_>) -> Result<(), MobileKeyTra
 mod tests {
     use super::{
         MobileKeyTransferError, MobileKeyTransferImport, MobileKeyTransferKind,
-        MobileKeyTransferService, encode_multipart,
+        MobileKeyTransferService, encode_multipart, load_keys_or_empty,
     };
     use crate::{config::Config, crypto::KeyStore, repository::SecretBytes};
     use tempfile::tempdir;
@@ -800,6 +815,36 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn cloned_store_with_empty_key_directory_can_import_its_private_key()
+    -> Result<(), Box<dyn std::error::Error>> {
+        let fixture = configured_key("placeholder", b"")?;
+        std::fs::remove_file(fixture.key_path.join("placeholder"))?;
+        let service = MobileKeyTransferService {
+            keys: load_keys_or_empty(&fixture.key_path)?,
+            config: fixture.config.clone(),
+        };
+        assert!(service.keys().is_empty());
+
+        let mut importer = service.importer();
+        importer.add_frame(SecretBytes::new(ALICE_SECRET.to_vec()))?;
+        importer.import(
+            Some(SecretBytes::new(b"fixture-alice-passphrase".to_vec())),
+            true,
+            false,
+        )?;
+
+        let keys = KeyStore::load(&fixture.key_path)?;
+        assert!(keys.resolve(ALICE_FINGERPRINT).is_ok());
+        assert_eq!(
+            Config::load(Some(fixture.config.source()))?
+                .default_key()
+                .as_str(),
+            ALICE_FINGERPRINT
+        );
+        Ok(())
+    }
+
     struct Fixture {
         _root: tempfile::TempDir,
         config: Config,