Simplify as per PR feedback.

src/PostgREST/Plan/Types.hs

@@ -1,31 +1,24 @@
 module PostgREST.Plan.Types
   ( TypedField(..)
-  , resolveField
   , resolveTableField
 
   ) where
 
 import qualified Data.HashMap.Strict.InsOrd as HMI
 
-import PostgREST.ApiRequest.Types (Field, JsonPath)
-
 import PostgREST.SchemaCache.Identifiers (FieldName)
 import PostgREST.SchemaCache.Table       (Column (..), Table (..))
 
 import Protolude
 
 -- | A TypedField is a field with sufficient information to be read from JSON with `json_to_recordset`.
 data TypedField = TypedField
-   { tfFieldName :: FieldName
-   , tfJsonPath  :: JsonPath
-   , tfIRType    :: Text
+   { tfName   :: FieldName
+   , tfIRType :: Text -- ^ The initial type of the field, before any casting.
    } deriving (Eq)
 
-resolveField :: Field -> Text -> TypedField
-resolveField (fieldName, jsonPath) = TypedField fieldName jsonPath
-
 resolveTableField :: Table -> FieldName -> Maybe TypedField
 resolveTableField table fieldName =
   case HMI.lookup fieldName (tableColumns table) of
-    Just column -> Just $ resolveField (colName column, []) (colNominalType column)
+    Just column -> Just $ TypedField (colName column) (colNominalType column)
     Nothing     -> Nothing

src/PostgREST/Query/QueryBuilder.hs

@@ -98,12 +98,12 @@ mutatePlanToQuery (Insert mainQi iCols body onConflct putConditions returnings _
         MergeDuplicates  ->
           if null iCols
              then "DO NOTHING"
-             else "DO UPDATE SET " <> BS.intercalate ", " ((pgFmtIdent . tfFieldName) <> const " = EXCLUDED." <> (pgFmtIdent . tfFieldName) <$> iCols)
+             else "DO UPDATE SET " <> BS.intercalate ", " ((pgFmtIdent . tfName) <> const " = EXCLUDED." <> (pgFmtIdent . tfName) <$> iCols)
       ) onConflct,
     returningF mainQi returnings
     ])
   where
-    cols = BS.intercalate ", " $ pgFmtIdent . tfFieldName <$> iCols
+    cols = BS.intercalate ", " $ pgFmtIdent . tfName <$> iCols
 
 -- An update without a limit is always filtered with a WHERE
 mutatePlanToQuery (Update mainQi uCols body logicForest range ordts returnings)
@@ -138,8 +138,8 @@ mutatePlanToQuery (Update mainQi uCols body logicForest range ordts returnings)
     whereLogic = if null logicForest then mempty else " WHERE " <> intercalateSnippet " AND " (pgFmtLogicTree mainQi <$> logicForest)
     mainTbl = SQL.sql (fromQi mainQi)
     emptyBodyReturnedColumns = if null returnings then "NULL" else BS.intercalate ", " (pgFmtColumn (QualifiedIdentifier mempty $ qiName mainQi) <$> returnings)
-    nonRangeCols = BS.intercalate ", " (pgFmtIdent . tfFieldName <> const " = _." <> pgFmtIdent . tfFieldName <$> uCols)
-    rangeCols = BS.intercalate ", " ((\col -> pgFmtIdent (tfFieldName col) <> " = (SELECT " <> pgFmtIdent (tfFieldName col) <> " FROM pgrst_update_body) ") <$> uCols)
+    nonRangeCols = BS.intercalate ", " (pgFmtIdent . tfName <> const " = _." <> pgFmtIdent . tfName <$> uCols)
+    rangeCols = BS.intercalate ", " ((\col -> pgFmtIdent (tfName col) <> " = (SELECT " <> pgFmtIdent (tfName col) <> " FROM pgrst_update_body) ") <$> uCols)
     (whereRangeIdF, rangeIdF) = mutRangeF mainQi (fst . otTerm <$> ordts)
 
 mutatePlanToQuery (Delete mainQi logicForest range ordts returnings)

src/PostgREST/Query/SqlFragment.hs

@@ -255,8 +255,8 @@ pgFmtSelectFromJson fields =
     else SQL.sql ("FROM json_to_recordset (" <> selectBody <> ") AS _ " <> "(" <> typedCols <> ") ")
   )
   where
-    parsedCols = SQL.sql $ BS.intercalate ", " $ pgFmtIdent . tfFieldName <$> fields
-    typedCols = BS.intercalate ", " $ pgFmtIdent . tfFieldName <> const " " <> encodeUtf8 . tfIRType <$> fields
+    parsedCols = SQL.sql $ BS.intercalate ", " $ pgFmtIdent . tfName <$> fields
+    typedCols = BS.intercalate ", " $ pgFmtIdent . tfName <> const " " <> encodeUtf8 . tfIRType <$> fields
 
 pgFmtOrderTerm :: QualifiedIdentifier -> OrderTerm -> SQL.Snippet
 pgFmtOrderTerm qi ot =