1 files changed, 26 insertions, 0 deletions
diff --git a/source/Test/Unit/Store.hs b/source/Test/Unit/Store.hs
index 9f25a3b..e2896c3 100644
--- a/source/Test/Unit/Store.hs
+++ b/source/Test/Unit/Store.hs
@@ -21,6 +21,7 @@ import Felix.Store qualified as Store
 import Provers qualified
 import Syntax.Interface qualified as Syntax
 
+import Control.Concurrent (threadDelay)
 import Control.Exception qualified as Exception
 import Data.ByteString qualified as ByteString
 import Data.ByteString.Char8 qualified as ByteString.Char8
@@ -33,6 +34,7 @@ import System.FilePath.Posix qualified as Posix
 import System.IO.Temp qualified as Temp
 import Test.Tasty
 import Test.Tasty.HUnit
+import UnliftIO.Async (concurrently)
 
 
 unitTests :: TestTree
@@ -40,6 +42,8 @@ unitTests =
     testGroup "SQLite store"
         [ testCase "initializes and reopens the current schema"
             initializesAndReopensCurrentSchema
+        , testCase "serializes invocation-local coordinator access"
+            serializesCoordinatorAccess
         , testCase "rejects incompatibility without configuring the store"
             rejectsIncompatibilityWithoutConfiguration
         , testCase "rejects malformed compatibility metadata"
@@ -80,6 +84,28 @@ unitTests =
             doesNotFallBackAfterFatalStartup
         ]
 
+serializesCoordinatorAccess :: Assertion
+serializesCoordinatorAccess = do
+    coordinator <- Store.newStoreCoordinator
+    active <- IORef.newIORef (0 :: Int)
+    maximumActive <- IORef.newIORef (0 :: Int)
+    let operation =
+            Store.withStoreCoordinator coordinator
+                (Exception.bracket_
+                    (IORef.atomicModifyIORef' active
+                        (\current ->
+                            let next = current + 1
+                            in (next, ())))
+                    (IORef.atomicModifyIORef' active
+                        (\current -> (current - 1, ())))
+                    (do
+                        current <- IORef.readIORef active
+                        IORef.atomicModifyIORef' maximumActive
+                            (\observed -> (max current observed, ()))
+                        threadDelay 50000))
+    void (concurrently operation operation)
+    IORef.readIORef maximumActive >>= assertEqual "maximum owner count" 1
+
 roundTripsExactParsedArtifacts :: Assertion
 roundTripsExactParsedArtifacts =
     withStoreFixture "felix-store-parsed" \path theory _fixture -> do