treewide: use whenTrue, whenFalse

Author: Anton-Latukha

.hlint.yaml

@@ -2682,11 +2682,17 @@
     note: "Use 'stub'"
     rhs: stub
 
-- warn:
-    lhs: "Data.Bool.bool True"
-    rhs: "Use `whenTrue` from HNix Prelude"
+- hint:
+    lhs: "bool mempty a b"
+    note: "Use `whenTrue`"
+    rhs: a `whenTrue` b
+
+- hint:
+    lhs: "bool a mempty b"
+    note: "Use `whenFalse`"
+    rhs: a `whenFalse` b
 
 - hint:
-    lhs: "maybe mempty"
+    lhs: "maybe mempty a b"
     note: "Use `whenJust`"
-    rhs: whenJust
+    rhs: a `whenJust` b

main/Repl.hs

@@ -248,7 +248,7 @@ exec update source = do
         (parseNixTextLoc i)
 
     toAttrSet i =
-      "{" <> i <> bool ";" mempty (Text.isSuffixOf ";" i) <> "}"
+      "{" <> i <> whenFalse ";" (Text.isSuffixOf ";" i) <> "}"
 
 cmd
   :: (MonadNix e t f m, MonadIO m)

src/Nix/Effects/Basic.hs

@@ -108,11 +108,7 @@ findEnvPathM name = do
         (toAbsolutePath @t @f $ coerce $ coerce absPath </> "default.nix")
         isDir
     exists <- doesFileExist absFile
-    pure $
-      bool
-        mempty
-        (pure absFile)
-        exists
+    pure $ pure absFile `whenTrue` exists
 
 findPathBy
   :: forall e t f m
@@ -147,10 +143,7 @@ findPathBy finder ls name = do
                   case mns of
                     Just (nsPfx :: NixString) ->
                       let pfx = stringIgnoreContext nsPfx in
-                      bool
-                        mempty
-                        (pure $ coerce $ toString pfx)
-                        (not $ Text.null pfx)
+                        pure $ coerce $ toString pfx `whenFalse` Text.null pfx
                     _ -> mempty
             )
             (M.lookup "prefix" s)

src/Nix/Expr/Shorthands.hs

@@ -124,7 +124,7 @@ mkNamedVariadicParamSet name params = mkGeneralParamSet (pure name) params True
 -- > False -> {}
 --  @since 0.15.0
 mkGeneralParamSet :: Maybe Text -> [(Text, Maybe NExpr)] -> Bool -> Params NExpr
-mkGeneralParamSet mname params variadic = ParamSet (coerce mname) (bool mempty Variadic variadic) (coerce params)
+mkGeneralParamSet mname params variadic = ParamSet (coerce mname) (Variadic `whenTrue` variadic) (coerce params)
 
 -- | > rec { .. }
 mkRecSet :: [Binding NExpr] -> NExpr
@@ -444,4 +444,4 @@ mkBinop = mkOp2
 --   * `mkVariadicSet` is for variadic;
 --   * `mkGeneralParamSet` a general constructor.
 mkParamset :: [(Text, Maybe NExpr)] -> Bool -> Params NExpr
-mkParamset params variadic = ParamSet Nothing (bool mempty Variadic variadic) (coerce params)
+mkParamset params variadic = ParamSet Nothing (Variadic `whenTrue` variadic) (coerce params)

src/Nix/Pretty.hs

@@ -136,18 +136,15 @@ prettyParams (ParamSet mname variadic pset) =
  where
   toDoc :: VarName -> Doc ann
   toDoc (coerce -> name) =
-    bool
-      mempty
-      ("@" <> pretty name)
-      (not (Text.null name))
+    ("@" <> pretty name) `whenFalse` Text.null name
 
 prettyParamSet :: Variadic -> ParamSet (NixDoc ann) -> Doc ann
 prettyParamSet variadic args =
   encloseSep
     "{ "
     (align " }")
     sep
-    (fmap prettySetArg args <> bool mempty ["..."] (variadic == Variadic))
+    (fmap prettySetArg args <> ["..."] `whenTrue` (variadic == Variadic))
  where
   prettySetArg (n, maybeDef) =
     maybe

src/Nix/Render.hs

@@ -119,14 +119,13 @@ sourceContext path (unPos -> begLine) (unPos -> _begCol) (unPos -> endLine) (unP
           | otherwise                    -> "    " <> nsp <> " |  "
       composeLine n l =
         [pretty (pad n) <> l]
-        <> bool mempty
-          [ pretty $
+        <> ([ pretty $
               Text.replicate (Text.length (pad n) - 3) " "
               <> "|"
               <> Text.replicate (_begCol + 1) " "
               <> Text.replicate (_endCol - _begCol) "^"
-          ]
-          (begLine == endLine && n == endLine)
+            ] `whenTrue` (begLine == endLine && n == endLine)
+          )
         -- XXX: Consider inserting the message here when it is small enough.
         -- ATM some messages are so huge that they take prevalence over the source listing.
         -- ++ [ indent (length $ pad n) msg | n == endLine ]

src/Nix/Render/Frame.hs

@@ -104,10 +104,7 @@ renderEvalFrame level f =
         do
           let
             scopeInfo =
-              bool
-                mempty
-                [pretty $ Text.show scope]
-                (showScopes opts)
+              [pretty $ Text.show scope] `whenTrue` showScopes opts
           fmap
             (\x -> scopeInfo <> [x])
             $ renderLocation ann =<<

src/Nix/Utils.hs

@@ -17,6 +17,7 @@ module Nix.Utils
   , stub
   , pass
   , whenTrue
+  , whenFalse
   , list
   , whenText
   , free
@@ -190,6 +191,14 @@ whenTrue =
     mempty
 {-# inline whenTrue #-}
 
+whenFalse :: (Monoid a)
+  => a  -> Bool  -> a
+whenFalse f =
+  bool
+    f
+    mempty
+{-# inline whenFalse #-}
+
 whenJust
   :: Monoid b
   => (a -> b)

src/Nix/Value.hs

@@ -729,10 +729,7 @@ valueType =
         NNull    -> TNull
     NVStrF ns  ->
       TString $
-        bool
-          mempty
-          HasContext
-          (stringHasContext ns)
+        HasContext `whenTrue` stringHasContext ns
     NVListF{}    -> TList
     NVSetF{}     -> TSet
     NVClosureF{} -> TClosure

src/Nix/XML.hs

@@ -106,10 +106,7 @@ paramsXML (ParamSet mname variadic pset) =
   [Elem $ Element (unqual "attrspat") (battr <> nattr) (paramSetXML pset) Nothing]
  where
   battr =
-    bool
-      mempty
-      [ Attr (unqual "ellipsis") "1" ]
-      (variadic == Variadic)
+    [ Attr (unqual "ellipsis") "1" ] `whenTrue` (variadic == Variadic)
   nattr =
     ((: mempty) . Attr (unqual "name") . toString) `whenJust` mname