Collect records on lists instead of maybe

This way we don't need to switch back and forward between the two,
and we can also return more than one match from inside a HsExpanded

Author: joyfulmantis

plugins/hls-overloaded-record-dot-plugin/src/Ide/Plugin/OverloadedRecordDot.hs

@@ -186,27 +186,27 @@ convertRecSel se re =
 -- It's important that we use everthingBut here, because if we used everything we would
 -- get duplicates for every case that occures inside a HsExpanded expression.
 collectRecordSelectors :: GenericQ [RecordSelectorExpr]
-collectRecordSelectors = everythingBut (<>) (first maybeToList. ((Nothing, False) `mkQ` getRecSels))
+collectRecordSelectors = everythingBut (<>) (([], False) `mkQ` getRecSels)
 
-getRecSels :: LHsExpr (GhcPass 'Renamed) -> (Maybe RecordSelectorExpr, Bool)
+getRecSels :: LHsExpr (GhcPass 'Renamed) -> ([RecordSelectorExpr], Bool)
 -- When we stumble upon an occurance of HsExpanded, we only want to follow one branch
--- we do this here, by explicitly returning an occurance from traversing the original branch,
+-- we do this here, by explicitly returning occurances from traversing the original branch,
 -- and returning True, which keeps syb from implicitly continuing to traverse.
-getRecSels (unLoc -> XExpr (HsExpanded a _)) = (listToMaybe $ collectRecordSelectors a, True)
+getRecSels (unLoc -> XExpr (HsExpanded a _)) = (collectRecordSelectors a, True)
 #if __GLASGOW_HASKELL__ >= 903
 -- applied record selection: "field record" or "field (record)" or "field field.record"
 getRecSels e@(unLoc -> HsApp _ se@(unLoc -> HsRecSel _ _) re) =
-  (listToMaybe [ RecordSelectorExpr (realSrcSpanToRange realSpan') se re | RealSrcSpan realSpan' _ <- [ getLoc e ]], False)
+  ( [ RecordSelectorExpr (realSrcSpanToRange realSpan') se re | RealSrcSpan realSpan' _ <- [ getLoc e ]], False)
 -- Record selection where the field is being applied with the "$" operator: "field $ record"
 getRecSels e@(unLoc -> OpApp _ se@(unLoc -> HsRecSel _ _) (unLoc -> HsVar _ (unLoc -> d)) re)
-    | d == dollarName = (listToMaybe [ RecordSelectorExpr (realSrcSpanToRange realSpan')  se re | RealSrcSpan realSpan' _ <- [ getLoc e ]], False)
+    | d == dollarName = ( [ RecordSelectorExpr (realSrcSpanToRange realSpan')  se re | RealSrcSpan realSpan' _ <- [ getLoc e ]], False)
 #else
 getRecSels e@(unLoc -> HsApp _ se@(unLoc -> HsRecFld _ _) re) =
-  (listToMaybe [ RecordSelectorExpr (realSrcSpanToRange realSpan') se re | RealSrcSpan realSpan' _ <- [ getLoc e ]], False)
+  ( [ RecordSelectorExpr (realSrcSpanToRange realSpan') se re | RealSrcSpan realSpan' _ <- [ getLoc e ]], False)
 getRecSels e@(unLoc -> OpApp _ se@(unLoc -> HsRecFld _ _) (unLoc -> HsVar _ (unLoc -> d)) re)
-    | d == dollarName = (listToMaybe [ RecordSelectorExpr (realSrcSpanToRange realSpan')  se re | RealSrcSpan realSpan' _ <- [ getLoc e ]], False)
+    | d == dollarName = ( [ RecordSelectorExpr (realSrcSpanToRange realSpan')  se re | RealSrcSpan realSpan' _ <- [ getLoc e ]], False)
 #endif
-getRecSels _ = (Nothing, False)
+getRecSels _ = ([], False)
 
 collectRecSelResult :: MonadIO m => IdeState -> NormalizedFilePath -> ExceptT String m CollectRecordSelectorsResult
 collectRecSelResult ideState =