refactor(users/Profpatsch/whatcd-resolver): move AppT & Html out r/7708

These functions are just general setup and html helpers, the main file
is getting a bit long otherwise.

Change-Id: I194e9f7f4caa4ce204d510c885dcf5af63d0e76e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11165
Autosubmit: Profpatsch <mail@profpatsch.de>
Reviewed-by: Profpatsch <mail@profpatsch.de>
Tested-by: BuildkiteCI

5 files changed, 212 insertions, 172 deletions

diff --git a/users/Profpatsch/whatcd-resolver/default.nix b/users/Profpatsch/whatcd-resolver/default.nix
index 17b6505c87..d209d65876 100644
--- a/users/Profpatsch/whatcd-resolver/default.nix
+++ b/users/Profpatsch/whatcd-resolver/default.nix
@@ -11,6 +11,8 @@ let
       ./whatcd-resolver.cabal
       ./Main.hs
       ./src/WhatcdResolver.hs
+      ./src/AppT.hs
+      ./src/Html.hs
     ];
 
     libraryHaskellDepends = [
diff --git a/users/Profpatsch/whatcd-resolver/src/AppT.hs b/users/Profpatsch/whatcd-resolver/src/AppT.hs
new file mode 100644
index 0000000000..bc94fc4ed5
--- /dev/null
+++ b/users/Profpatsch/whatcd-resolver/src/AppT.hs
@@ -0,0 +1,120 @@
+{-# LANGUAGE DeriveAnyClass #-}
+
+module AppT where
+
+import Control.Monad.Logger qualified as Logger
+import Control.Monad.Logger.CallStack
+import Control.Monad.Reader
+import Data.Error.Tree
+import Data.HashMap.Strict qualified as HashMap
+import Data.Pool (Pool)
+import Data.Text qualified as Text
+import Database.PostgreSQL.Simple qualified as Postgres
+import GHC.Stack qualified
+import Label
+import OpenTelemetry.Trace qualified as Otel hiding (getTracer, inSpan, inSpan')
+import OpenTelemetry.Trace.Core qualified as Otel hiding (inSpan, inSpan')
+import OpenTelemetry.Trace.Monad qualified as Otel
+import PossehlAnalyticsPrelude
+import Postgres.MonadPostgres
+import System.IO qualified as IO
+import Tool (Tool)
+import UnliftIO
+import Prelude hiding (span)
+
+data Context = Context
+  { config :: Label "logDatabaseQueries" DebugLogDatabaseQueries,
+    tracer :: Otel.Tracer,
+    pgFormat :: Tool,
+    pgConnPool :: Pool Postgres.Connection,
+    transmissionSessionId :: MVar ByteString
+  }
+
+newtype AppT m a = AppT {unAppT :: ReaderT Context m a}
+  deriving newtype (Functor, Applicative, Monad, MonadIO, MonadUnliftIO, MonadThrow)
+
+data AppException = AppException Text
+  deriving stock (Show)
+  deriving anyclass (Exception)
+
+-- *  Logging & Opentelemetry
+
+instance (MonadIO m) => MonadLogger (AppT m) where
+  monadLoggerLog loc src lvl msg = liftIO $ Logger.defaultOutput IO.stderr loc src lvl (Logger.toLogStr msg)
+
+instance (Monad m) => Otel.MonadTracer (AppT m) where
+  getTracer = AppT $ asks (.tracer)
+
+inSpan :: (MonadUnliftIO m, Otel.MonadTracer m) => Text -> m a -> m a
+inSpan name = Otel.inSpan name Otel.defaultSpanArguments
+
+inSpan' :: (MonadUnliftIO m, Otel.MonadTracer m) => Text -> (Otel.Span -> m a) -> m a
+inSpan' name = Otel.inSpan' name Otel.defaultSpanArguments
+
+appThrowTree :: (MonadThrow m, MonadIO m) => Otel.Span -> ErrorTree -> m a
+appThrowTree span exc = do
+  let msg = prettyErrorTree exc
+  recordException
+    span
+    ( T2
+        (label @"type_" "AppException")
+        (label @"message" msg)
+    )
+  throwM $ AppException msg
+
+orAppThrowTree :: (MonadThrow m, MonadIO m) => Otel.Span -> Either ErrorTree a -> m a
+orAppThrowTree span = \case
+  Left err -> appThrowTree span err
+  Right a -> pure a
+
+assertM :: (MonadThrow f, MonadIO f) => Otel.Span -> (t -> Either ErrorTree a) -> t -> f a
+assertM span f v = case f v of
+  Right a -> pure a
+  Left err -> appThrowTree span err
+
+-- | A specialized variant of @addEvent@ that records attributes conforming to
+-- the OpenTelemetry specification's
+-- <https://github.com/open-telemetry/opentelemetry-specification/blob/49c2f56f3c0468ceb2b69518bcadadd96e0a5a8b/specification/trace/semantic_conventions/exceptions.md semantic conventions>
+--
+-- @since 0.0.1.0
+recordException ::
+  ( MonadIO m,
+    HasField "message" r Text,
+    HasField "type_" r Text
+  ) =>
+  Otel.Span ->
+  r ->
+  m ()
+recordException span dat = liftIO $ do
+  callStack <- GHC.Stack.whoCreated dat.message
+  newEventTimestamp <- Just <$> Otel.getTimestamp
+  Otel.addEvent span $
+    Otel.NewEvent
+      { newEventName = "exception",
+        newEventAttributes =
+          HashMap.fromList
+            [ ("exception.type", Otel.toAttribute @Text dat.type_),
+              ("exception.message", Otel.toAttribute @Text dat.message),
+              ("exception.stacktrace", Otel.toAttribute @Text $ Text.unlines $ map stringToText callStack)
+            ],
+        ..
+      }
+
+-- * Postgres
+
+instance (MonadThrow m, MonadUnliftIO m) => MonadPostgres (AppT m) where
+  execute = executeImpl (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
+  execute_ = executeImpl_ (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
+  executeMany = executeManyImpl (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
+  executeManyReturningWith = executeManyReturningWithImpl (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
+  queryWith = queryWithImpl (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
+  queryWith_ = queryWithImpl_ (AppT ask)
+  foldRows = foldRowsImpl (AppT ask)
+  runTransaction = runPGTransaction
+
+runPGTransaction :: (MonadUnliftIO m) => Transaction (AppT m) a -> AppT m a
+runPGTransaction (Transaction transaction) = do
+  pool <- AppT ask <&> (.pgConnPool)
+  withRunInIO $ \unliftIO ->
+    withPGTransaction pool $ \conn -> do
+      unliftIO $ runReaderT transaction conn
diff --git a/users/Profpatsch/whatcd-resolver/src/Html.hs b/users/Profpatsch/whatcd-resolver/src/Html.hs
new file mode 100644
index 0000000000..49b87b23dc
--- /dev/null
+++ b/users/Profpatsch/whatcd-resolver/src/Html.hs
@@ -0,0 +1,69 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Html where
+
+import Data.Aeson qualified as Json
+import Data.Aeson.KeyMap qualified as KeyMap
+import Data.List.NonEmpty qualified as NonEmpty
+import Data.Map.Strict qualified as Map
+import IHP.HSX.QQ (hsx)
+import PossehlAnalyticsPrelude
+import Text.Blaze.Html (Html)
+import Text.Blaze.Html5 qualified as Html
+import Prelude hiding (span)
+
+-- | Render an arbitrary json value to HTML in a more-or-less reasonable fashion.
+mkVal :: Json.Value -> Html
+mkVal = \case
+  Json.Number n -> Html.toHtml @Text $ showToText n
+  Json.String s -> Html.toHtml @Text s
+  Json.Bool True -> [hsx|<em>true</em>|]
+  Json.Bool False -> [hsx|<em>false</em>|]
+  Json.Null -> [hsx|<em>null</em>|]
+  Json.Array arr -> toOrderedList mkVal arr
+  Json.Object obj ->
+    obj
+      & KeyMap.toMapText
+      & toDefinitionList (Html.toHtml @Text) mkVal
+
+toOrderedList :: (Foldable t1) => (t2 -> Html) -> t1 t2 -> Html
+toOrderedList mkValFn arr =
+  arr
+    & foldMap (\el -> Html.li $ mkValFn el)
+    & Html.ol
+
+toUnorderedList :: (Foldable t1) => (t2 -> Html) -> t1 t2 -> Html
+toUnorderedList mkValFn arr =
+  arr
+    & foldMap (\el -> Html.li $ mkValFn el)
+    & Html.ul
+
+-- | Render a definition list from a Map
+toDefinitionList :: (Text -> Html) -> (t -> Html) -> Map Text t -> Html
+toDefinitionList mkKeyFn mkValFn obj =
+  obj
+    & Map.toList
+    & foldMap (\(k, v) -> Html.dt (mkKeyFn k) <> Html.dd (mkValFn v))
+    & Html.dl
+
+-- | Render a table-like structure of json values as an HTML table.
+toTable :: [[(Text, Json.Value)]] -> Html
+toTable xs =
+  case xs & nonEmpty of
+    Nothing ->
+      [hsx|<p>No results.</p>|]
+    Just xs' -> do
+      let headers = xs' & NonEmpty.head <&> fst <&> (\h -> [hsx|<th>{h}</th>|]) & mconcat
+      let vals = xs' & foldMap (Html.tr . foldMap (Html.td . mkVal . snd))
+      [hsx|
+              <table class="table">
+                <thead>
+                  <tr>
+                  {headers}
+                  </tr>
+                </thead>
+                <tbody>
+                  {vals}
+                </tbody>
+              </table>
+          |]
diff --git a/users/Profpatsch/whatcd-resolver/src/WhatcdResolver.hs b/users/Profpatsch/whatcd-resolver/src/WhatcdResolver.hs
index 6866d387cb..e5d6ba5f80 100644
--- a/users/Profpatsch/whatcd-resolver/src/WhatcdResolver.hs
+++ b/users/Profpatsch/whatcd-resolver/src/WhatcdResolver.hs
@@ -1,13 +1,10 @@
-{-# LANGUAGE DeriveAnyClass #-}
-{-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE QuasiQuotes #-}
-{-# LANGUAGE ScopedTypeVariables #-}
 
 module WhatcdResolver where
 
+import AppT
 import Control.Category qualified as Cat
 import Control.Monad.Catch.Pure (runCatch)
-import Control.Monad.Logger qualified as Logger
 import Control.Monad.Logger.CallStack
 import Control.Monad.Reader
 import Data.Aeson qualified as Json
@@ -19,7 +16,6 @@ import Data.HashMap.Strict qualified as HashMap
 import Data.List qualified as List
 import Data.List.NonEmpty qualified as NonEmpty
 import Data.Map.Strict qualified as Map
-import Data.Pool (Pool)
 import Data.Pool qualified as Pool
 import Data.Set (Set)
 import Data.Set qualified as Set
@@ -32,7 +28,7 @@ import Database.Postgres.Temp qualified as TmpPg
 import FieldParser (FieldParser, FieldParser' (..))
 import FieldParser qualified as Field
 import GHC.Records (HasField (..))
-import GHC.Stack qualified
+import Html qualified
 import IHP.HSX.QQ (hsx)
 import Json qualified
 import Json.Enc (Enc)
@@ -49,7 +45,6 @@ import Network.Wai qualified as Wai
 import Network.Wai.Handler.Warp qualified as Warp
 import Network.Wai.Parse qualified as Wai
 import OpenTelemetry.Trace qualified as Otel hiding (getTracer, inSpan, inSpan')
-import OpenTelemetry.Trace.Core qualified as Otel hiding (inSpan, inSpan')
 import OpenTelemetry.Trace.Monad qualified as Otel
 import Parse (Parse)
 import Parse qualified
@@ -62,12 +57,11 @@ import System.Directory qualified as Dir
 import System.Directory qualified as Xdg
 import System.Environment qualified as Env
 import System.FilePath ((</>))
-import System.IO qualified as IO
 import Text.Blaze.Html (Html)
 import Text.Blaze.Html.Renderer.Pretty qualified as Html.Pretty
 import Text.Blaze.Html.Renderer.Utf8 qualified as Html
 import Text.Blaze.Html5 qualified as Html
-import Tool (Tool, readTool, readTools)
+import Tool (readTool, readTools)
 import UnliftIO
 import Prelude hiding (span)
 
@@ -144,7 +138,7 @@ htmlUi = do
             snipsRedactedSearch dat
         "snips/redacted/torrentDataJson" -> h "/snips/redacted/torrentDataJson" $ \span -> do
           dat <- torrentIdMp span
-          mkVal <$> (runTransaction $ getTorrentById dat)
+          Html.mkVal <$> (runTransaction $ getTorrentById dat)
         "snips/redacted/getTorrentFile" -> h "/snips/redacted/getTorrentFile" $ \span -> do
           dat <- torrentIdMp span
           runTransaction $ do
@@ -449,7 +443,7 @@ renderJsonld = \case
       <dd><a href={obj.id_}>{obj.id_}</a></dd>
       <dt>Fields</dt>
       <dd>
-        {obj.previewFields & toDefinitionList schemaType renderJsonld}
+        {obj.previewFields & Html.toDefinitionList schemaType renderJsonld}
         <div>
           <button
             hx-get={snippetHref obj.id_}
@@ -474,8 +468,8 @@ renderJsonld = \case
       schemaType t =
         let href :: Text = [fmt|https://schema.org/{t}|] in [hsx|<a href={href} target="_blank">{t}</a>|]
   JsonldArray arr ->
-    toOrderedList renderJsonld arr
-  JsonldField f -> mkVal f
+    Html.toOrderedList renderJsonld arr
+  JsonldField f -> Html.mkVal f
 
 -- | A value between (inclusive) 0% and (inclusive) 100%. Precise to 1% steps.
 newtype Percentage = Percentage {unPercentage :: Int}
@@ -546,7 +540,7 @@ getTransmissionTorrentsTable = do
         Json.asObject <&> KeyMap.toMapText
     )
     <&> \resp ->
-      toTable
+      Html.toTable
         ( resp
             & List.sortOn (\m -> m & Map.lookup "percentDone" & fromMaybe (Json.Number 0))
             <&> Map.toList
@@ -554,62 +548,6 @@ getTransmissionTorrentsTable = do
             & List.take 100
         )
 
--- | Render an arbitrary json value to HTML in a more-or-less reasonable fashion.
-mkVal :: Json.Value -> Html
-mkVal = \case
-  Json.Number n -> Html.toHtml @Text $ showToText n
-  Json.String s -> Html.toHtml @Text s
-  Json.Bool True -> [hsx|<em>true</em>|]
-  Json.Bool False -> [hsx|<em>false</em>|]
-  Json.Null -> [hsx|<em>null</em>|]
-  Json.Array arr -> toOrderedList mkVal arr
-  Json.Object obj ->
-    obj
-      & KeyMap.toMapText
-      & toDefinitionList (Html.toHtml @Text) mkVal
-
-toOrderedList :: (Foldable t1) => (t2 -> Html) -> t1 t2 -> Html
-toOrderedList mkValFn arr =
-  arr
-    & foldMap (\el -> Html.li $ mkValFn el)
-    & Html.ol
-
-toUnorderedList :: (Foldable t1) => (t2 -> Html) -> t1 t2 -> Html
-toUnorderedList mkValFn arr =
-  arr
-    & foldMap (\el -> Html.li $ mkValFn el)
-    & Html.ul
-
--- | Render a definition list from a Map
-toDefinitionList :: (Text -> Html) -> (t -> Html) -> Map Text t -> Html
-toDefinitionList mkKeyFn mkValFn obj =
-  obj
-    & Map.toList
-    & foldMap (\(k, v) -> Html.dt (mkKeyFn k) <> Html.dd (mkValFn v))
-    & Html.dl
-
--- | Render a table-like structure of json values as an HTML table.
-toTable :: [[(Text, Json.Value)]] -> Html
-toTable xs =
-  case xs & nonEmpty of
-    Nothing ->
-      [hsx|<p>No results.</p>|]
-    Just xs' -> do
-      let headers = xs' & NonEmpty.head <&> fst <&> (\h -> [hsx|<th>{h}</th>|]) & mconcat
-      let vals = xs' & foldMap (Html.tr . foldMap (Html.td . mkVal . snd))
-      [hsx|
-              <table class="table">
-                <thead>
-                  <tr>
-                  {headers}
-                  </tr>
-                </thead>
-                <tbody>
-                  {vals}
-                </tbody>
-              </table>
-          |]
-
 data TransmissionRequest = TransmissionRequest
   { method :: Text,
     arguments :: Map Text Enc,
@@ -831,10 +769,10 @@ redactedGetTorrentFile dat = inSpan' "Redacted Get Torrent File" $ \span -> do
           (label @"action" "download")
           ( label @"actionArgs"
               [ ("id", Just (dat.torrentId & showToText @Int & textToBytesUtf8))
-                -- try using tokens as long as we have them (TODO: what if there’s no tokens left?
-                -- ANSWER: it breaks:
-                -- responseBody = "{\"status\":\"failure\",\"error\":\"You do not have any freeleech tokens left. Please use the regular DL link.\"}",
-                -- ("usetoken", Just "1")
+              -- try using tokens as long as we have them (TODO: what if there’s no tokens left?
+              -- ANSWER: it breaks:
+              -- responseBody = "{\"status\":\"failure\",\"error\":\"You do not have any freeleech tokens left. Please use the regular DL link.\"}",
+              -- ("usetoken", Just "1")
               ]
           )
       )
@@ -1262,16 +1200,6 @@ getBestTorrents = do
             }
     )
 
-inSpan :: (MonadUnliftIO m, Otel.MonadTracer m) => Text -> m a -> m a
-inSpan name = Otel.inSpan name Otel.defaultSpanArguments
-
-inSpan' :: (MonadUnliftIO m, Otel.MonadTracer m) => Text -> (Otel.Span -> m a) -> m a
-inSpan' name = Otel.inSpan' name Otel.defaultSpanArguments
-
-hush :: Either a1 a2 -> Maybe a2
-hush (Left _) = Nothing
-hush (Right a) = Just a
-
 -- | Do a request to the redacted API. If you know what that is, you know how to find the API docs.
 mkRedactedApiRequest ::
   ( MonadThrow m,
@@ -1404,11 +1332,6 @@ redactedApiRequestJson span dat parser =
     mkRedactedApiRequest dat
     >>= httpJson defaults span parser
 
-assertM :: (MonadThrow f, MonadIO f) => Otel.Span -> (t -> Either ErrorTree a) -> t -> f a
-assertM span f v = case f v of
-  Right a -> pure a
-  Left err -> appThrowTree span err
-
 runAppWith :: AppT IO a -> IO (Either TmpPg.StartError a)
 runAppWith appT = withTracer $ \tracer -> withDb $ \db -> do
   pgFormat <- readTools (label @"toolsEnvVar" "WHATCD_RESOLVER_TOOLS") (readTool "pg_format")
@@ -1469,71 +1392,6 @@ withDb act = do
     -- print [fmt|conn string: {db & TmpPg.toConnectionString}|]
     act db
 
-data Context = Context
-  { config :: Label "logDatabaseQueries" DebugLogDatabaseQueries,
-    tracer :: Otel.Tracer,
-    pgFormat :: Tool,
-    pgConnPool :: Pool Postgres.Connection,
-    transmissionSessionId :: MVar ByteString
-  }
-
-newtype AppT m a = AppT {unAppT :: ReaderT Context m a}
-  deriving newtype (Functor, Applicative, Monad, MonadIO, MonadUnliftIO, MonadThrow)
-
-data AppException = AppException Text
-  deriving stock (Show)
-  deriving anyclass (Exception)
-
--- | A specialized variant of @addEvent@ that records attributes conforming to
--- the OpenTelemetry specification's
--- <https://github.com/open-telemetry/opentelemetry-specification/blob/49c2f56f3c0468ceb2b69518bcadadd96e0a5a8b/specification/trace/semantic_conventions/exceptions.md semantic conventions>
---
--- @since 0.0.1.0
-recordException ::
-  ( MonadIO m,
-    HasField "message" r Text,
-    HasField "type_" r Text
-  ) =>
-  Otel.Span ->
-  r ->
-  m ()
-recordException span dat = liftIO $ do
-  callStack <- GHC.Stack.whoCreated dat.message
-  newEventTimestamp <- Just <$> Otel.getTimestamp
-  Otel.addEvent span $
-    Otel.NewEvent
-      { newEventName = "exception",
-        newEventAttributes =
-          HashMap.fromList
-            [ ("exception.type", Otel.toAttribute @Text dat.type_),
-              ("exception.message", Otel.toAttribute @Text dat.message),
-              ("exception.stacktrace", Otel.toAttribute @Text $ Text.unlines $ map stringToText callStack)
-            ],
-        ..
-      }
-
-appThrowTree :: (MonadThrow m, MonadIO m) => Otel.Span -> ErrorTree -> m a
-appThrowTree span exc = do
-  let msg = prettyErrorTree exc
-  recordException
-    span
-    ( T2
-        (label @"type_" "AppException")
-        (label @"message" msg)
-    )
-  throwM $ AppException msg
-
-orAppThrowTree :: (MonadThrow m, MonadIO m) => Otel.Span -> Either ErrorTree a -> m a
-orAppThrowTree span = \case
-  Left err -> appThrowTree span err
-  Right a -> pure a
-
-instance (MonadIO m) => MonadLogger (AppT m) where
-  monadLoggerLog loc src lvl msg = liftIO $ Logger.defaultOutput IO.stderr loc src lvl (Logger.toLogStr msg)
-
-instance (Monad m) => Otel.MonadTracer (AppT m) where
-  getTracer = AppT $ asks (.tracer)
-
 class MonadTransmission m where
   getTransmissionId :: m (Maybe ByteString)
   setTransmissionId :: ByteString -> m ()
@@ -1543,20 +1401,3 @@ instance (MonadIO m) => MonadTransmission (AppT m) where
   setTransmissionId t = do
     var <- AppT $ asks (.transmissionSessionId)
     putMVar var t
-
-instance (MonadThrow m, MonadUnliftIO m) => MonadPostgres (AppT m) where
-  execute = executeImpl (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
-  execute_ = executeImpl_ (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
-  executeMany = executeManyImpl (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
-  executeManyReturningWith = executeManyReturningWithImpl (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
-  queryWith = queryWithImpl (AppT ask) (AppT $ asks (.config.logDatabaseQueries))
-  queryWith_ = queryWithImpl_ (AppT ask)
-  foldRows = foldRowsImpl (AppT ask)
-  runTransaction = runPGTransaction
-
-runPGTransaction :: (MonadUnliftIO m) => Transaction (AppT m) a -> AppT m a
-runPGTransaction (Transaction transaction) = do
-  pool <- AppT ask <&> (.pgConnPool)
-  withRunInIO $ \unliftIO ->
-    withPGTransaction pool $ \conn -> do
-      unliftIO $ runReaderT transaction conn
diff --git a/users/Profpatsch/whatcd-resolver/whatcd-resolver.cabal b/users/Profpatsch/whatcd-resolver/whatcd-resolver.cabal
index cca3712a65..614772db24 100644
--- a/users/Profpatsch/whatcd-resolver/whatcd-resolver.cabal
+++ b/users/Profpatsch/whatcd-resolver/whatcd-resolver.cabal
@@ -35,6 +35,10 @@ common common-options
     -- does not export record fields as functions, use OverloadedRecordDot to access instead
     NoFieldSelectors
 
+    -- Allow the same record field name to be declared twice per module.
+    -- This works, because we use `OverloadedRecordDot` everywhere (enforced by `NoFieldSelectors`).
+    DuplicateRecordFields
+
     -- Record punning
     RecordWildCards
 
@@ -48,8 +52,10 @@ common common-options
     -- to enable the `type` keyword in import lists (ormolu uses this automatically)
     ExplicitNamespaces
 
-  default-language: GHC2021
+    -- allows defining pattern synonyms, but also the `import Foo (pattern FooPattern)` import syntax
+    PatternSynonyms
 
+  default-language: GHC2021
 
 library
     import: common-options
@@ -58,6 +64,8 @@ library
 
     exposed-modules:
        WhatcdResolver
+       AppT
+       Html
 
     build-depends:
         base >=4.15 && <5,