Add Unison.Runtime.Resource pool naive test

Using a hard-coded acquire and release, test that acquire correctly
passes along its value.

node/runtests.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+# I always forget this flag
+cabal test --show-details=streaming

node/src/Unison/Runtime/ResourcePool.hs

@@ -0,0 +1,15 @@
+module Unison.Runtime.ResourcePool where
+
+import qualified Data.Map as M
+
+-- acquire returns the resource, and the cleanup action ("finalizer") for that resource
+data Pool p r = Pool { acquire :: p -> IO (r, IO ()) }
+
+iacquire :: (p -> IO r) -> p -> IO (r, IO ())
+iacquire a p = do
+  r <- a p
+  return (r, return ())
+
+pool :: Ord p => Int -> (p -> IO r) -> (r -> IO ()) -> IO (Pool p r)
+pool maxPoolSize a release =
+  return $ Pool { acquire = iacquire a }

node/tests/Suite.hs

@@ -0,0 +1,10 @@
+module Main where
+
+import Test.Tasty
+import qualified Unison.Test.ResourcePool as ResourcePool
+
+tests :: TestTree
+tests = testGroup "unison" [ResourcePool.tests]
+
+main :: IO ()
+main = defaultMain tests

node/tests/Unison/Test/ResourcePool.hs

@@ -0,0 +1,28 @@
+module Unison.Test.ResourcePool where
+
+import qualified Unison.Runtime.ResourcePool as RP
+import Test.Tasty
+import Test.Tasty.HUnit
+
+type Resource = String
+type Params = String
+
+fakeAcquire :: Params -> IO Resource
+fakeAcquire p = return "r1"
+
+fakeRelease :: Resource -> IO ()
+fakeRelease r = return ()
+
+correctlyReturnsTest :: Assertion
+correctlyReturnsTest = do
+  pool <- (RP.pool 3 fakeAcquire fakeRelease)
+  (r, _) <- RP.acquire pool "p1"
+  assertEqual "the correct resource is returned" "r1" r
+
+tests :: TestTree
+tests = testGroup "Doc"
+  [
+    testCase "Test" $ correctlyReturnsTest
+  ]
+
+main = defaultMain tests

node/unison-node.cabal

@@ -56,6 +56,7 @@ library
     Unison.Runtime.Pcbt
     Unison.Runtime.Unfold
     Unison.Runtime.Vector
+    Unison.Runtime.ResourcePool
 
   build-depends:
     aeson,
@@ -125,3 +126,19 @@ executable node
     vector,
     wai-middleware-static,
     wai-extra
+
+test-suite tests
+  type:           exitcode-stdio-1.0
+  main-is:        Suite.hs
+  ghc-options:    -w -threaded -rtsopts -with-rtsopts=-N -v0
+  hs-source-dirs: tests
+  other-modules:
+  build-depends:
+    base,
+    containers,
+    tasty,
+    tasty-hunit,
+    tasty-smallcheck,
+    tasty-quickcheck,
+    transformers,
+    unison-node

shared/runtests.sh

@@ -1,3 +1,4 @@
 #!/bin/sh
+# run 'stack test" to correctly configure this
 # I always forget this flag
 cabal test --show-details=streaming