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author | Ryan Scott <ryan.gl.scott@gmail.com> | 2020-06-23 17:50:15 -0400 |
---|---|---|
committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2020-06-28 09:19:46 -0400 |
commit | 42f797b0ad034a92389e7081aa50ef4ab3434d01 (patch) | |
tree | 8a198d5f6b2e51fe3578586c44445d76dbe4e96d /testsuite | |
parent | d8ba9e6f951a2f8c6e2429a8b2dcb035c392908f (diff) | |
download | haskell-42f797b0ad034a92389e7081aa50ef4ab3434d01.tar.gz |
Use NHsCoreTy to embed types into GND-generated code
`GeneralizedNewtypeDeriving` is in the unique situation where it must
produce an `LHsType GhcPs` from a Core `Type`. Historically, this was
done with the `typeToLHsType` function, which walked over the entire
`Type` and attempted to construct an `LHsType` with the same overall
structure. `typeToLHsType` is quite complicated, however, and has
been the subject of numerous bugs over the years (e.g., #14579).
Luckily, there is an easier way to accomplish the same thing: the
`XHsType` constructor of `HsType`. `XHsType` bundles an `NHsCoreTy`,
which allows embedding a Core `Type` directly into an `HsType`,
avoiding the need to laboriously convert from one to another (as
`typeToLHsType` did). Moreover, renaming and typechecking an
`XHsType` is simple, since one doesn't need to do anything to a
Core `Type`...
...well, almost. For the reasons described in
`Note [Typechecking NHsCoreTys]` in `GHC.Tc.Gen.HsType`, we must
apply a substitution that we build from the local `tcl_env` type
environment. But that's a relatively modest price to pay.
Now that `GeneralizedNewtypeDeriving` uses `NHsCoreTy`, the
`typeToLHsType` function no longer has any uses in GHC, so this patch
rips it out. Some additional tweaks to `hsTypeNeedsParens` were
necessary to make the new `-ddump-deriv` output correctly
parenthesized, but other than that, this patch is quite
straightforward.
This is a mostly internal refactoring, although it is likely that
`GeneralizedNewtypeDeriving`-generated code will now need fewer
language extensions in certain situations than it did before.
Diffstat (limited to 'testsuite')
4 files changed, 37 insertions, 49 deletions
diff --git a/testsuite/tests/deriving/should_compile/T14578.stderr b/testsuite/tests/deriving/should_compile/T14578.stderr index 58376989db..0018ebe569 100644 --- a/testsuite/tests/deriving/should_compile/T14578.stderr +++ b/testsuite/tests/deriving/should_compile/T14578.stderr @@ -9,18 +9,20 @@ Derived class instances: GHC.Base.sconcat :: GHC.Base.NonEmpty (T14578.Wat f g a) -> T14578.Wat f g a GHC.Base.stimes :: - forall (b :: TYPE 'GHC.Types.LiftedRep). - GHC.Real.Integral b => b -> T14578.Wat f g a -> T14578.Wat f g a + forall b. + GHC.Real.Integral b => + b -> T14578.Wat f g a -> T14578.Wat f g a (GHC.Base.<>) = GHC.Prim.coerce @(T14578.App (Data.Functor.Compose.Compose f g) a -> T14578.App (Data.Functor.Compose.Compose f g) a - -> T14578.App (Data.Functor.Compose.Compose f g) a) + -> T14578.App (Data.Functor.Compose.Compose f g) a) @(T14578.Wat f g a -> T14578.Wat f g a -> T14578.Wat f g a) ((GHC.Base.<>) @(T14578.App (Data.Functor.Compose.Compose f g) a)) GHC.Base.sconcat = GHC.Prim.coerce - @(GHC.Base.NonEmpty (T14578.App (Data.Functor.Compose.Compose f g) a) + @(GHC.Base.NonEmpty + (T14578.App (Data.Functor.Compose.Compose f g) a) -> T14578.App (Data.Functor.Compose.Compose f g) a) @(GHC.Base.NonEmpty (T14578.Wat f g a) -> T14578.Wat f g a) (GHC.Base.sconcat @@ -29,7 +31,7 @@ Derived class instances: = GHC.Prim.coerce @(b -> T14578.App (Data.Functor.Compose.Compose f g) a - -> T14578.App (Data.Functor.Compose.Compose f g) a) + -> T14578.App (Data.Functor.Compose.Compose f g) a) @(b -> T14578.Wat f g a -> T14578.Wat f g a) (GHC.Base.stimes @(T14578.App (Data.Functor.Compose.Compose f g) a)) @@ -37,13 +39,8 @@ Derived class instances: instance GHC.Base.Functor f => GHC.Base.Functor (T14578.App f) where GHC.Base.fmap :: - forall (a :: TYPE 'GHC.Types.LiftedRep) - (b :: TYPE 'GHC.Types.LiftedRep). - (a -> b) -> T14578.App f a -> T14578.App f b - (GHC.Base.<$) :: - forall (a :: TYPE 'GHC.Types.LiftedRep) - (b :: TYPE 'GHC.Types.LiftedRep). - a -> T14578.App f b -> T14578.App f a + forall a b. (a -> b) -> T14578.App f a -> T14578.App f b + (GHC.Base.<$) :: forall a b. a -> T14578.App f b -> T14578.App f a GHC.Base.fmap = GHC.Prim.coerce @((a -> b) -> f a -> f b) @@ -55,25 +52,17 @@ Derived class instances: instance GHC.Base.Applicative f => GHC.Base.Applicative (T14578.App f) where - GHC.Base.pure :: - forall (a :: TYPE 'GHC.Types.LiftedRep). a -> T14578.App f a + GHC.Base.pure :: forall a. a -> T14578.App f a (GHC.Base.<*>) :: - forall (a :: TYPE 'GHC.Types.LiftedRep) - (b :: TYPE 'GHC.Types.LiftedRep). + forall a b. T14578.App f (a -> b) -> T14578.App f a -> T14578.App f b GHC.Base.liftA2 :: - forall (a :: TYPE 'GHC.Types.LiftedRep) - (b :: TYPE 'GHC.Types.LiftedRep) - (c :: TYPE 'GHC.Types.LiftedRep). + forall a b c. (a -> b -> c) -> T14578.App f a -> T14578.App f b -> T14578.App f c (GHC.Base.*>) :: - forall (a :: TYPE 'GHC.Types.LiftedRep) - (b :: TYPE 'GHC.Types.LiftedRep). - T14578.App f a -> T14578.App f b -> T14578.App f b + forall a b. T14578.App f a -> T14578.App f b -> T14578.App f b (GHC.Base.<*) :: - forall (a :: TYPE 'GHC.Types.LiftedRep) - (b :: TYPE 'GHC.Types.LiftedRep). - T14578.App f a -> T14578.App f b -> T14578.App f a + forall a b. T14578.App f a -> T14578.App f b -> T14578.App f a GHC.Base.pure = GHC.Prim.coerce @(a -> f a) @(a -> T14578.App f a) (GHC.Base.pure @f) @@ -105,15 +94,13 @@ Derived type family instances: ==================== Filling in method body ==================== -GHC.Base.Semigroup [T14578.App f[ssk:1] a[ssk:1]] - GHC.Base.sconcat = GHC.Base.$dmsconcat - @(T14578.App f[ssk:1] a[ssk:1]) +GHC.Base.Semigroup [T14578.App f a] + GHC.Base.sconcat = GHC.Base.$dmsconcat @(T14578.App f a) ==================== Filling in method body ==================== -GHC.Base.Semigroup [T14578.App f[ssk:1] a[ssk:1]] - GHC.Base.stimes = GHC.Base.$dmstimes - @(T14578.App f[ssk:1] a[ssk:1]) +GHC.Base.Semigroup [T14578.App f a] + GHC.Base.stimes = GHC.Base.$dmstimes @(T14578.App f a) diff --git a/testsuite/tests/deriving/should_compile/T14579.stderr b/testsuite/tests/deriving/should_compile/T14579.stderr index 81212022ef..31545c6de7 100644 --- a/testsuite/tests/deriving/should_compile/T14579.stderr +++ b/testsuite/tests/deriving/should_compile/T14579.stderr @@ -8,34 +8,36 @@ Derived class instances: T14579.Glurp a -> T14579.Glurp a -> GHC.Types.Bool (GHC.Classes.==) = GHC.Prim.coerce - @(T14579.Wat @a ('Data.Proxy.Proxy @a) - -> T14579.Wat @a ('Data.Proxy.Proxy @a) -> GHC.Types.Bool) + @(T14579.Wat 'Data.Proxy.Proxy + -> T14579.Wat 'Data.Proxy.Proxy -> GHC.Types.Bool) @(T14579.Glurp a -> T14579.Glurp a -> GHC.Types.Bool) - ((GHC.Classes.==) @(T14579.Wat @a ('Data.Proxy.Proxy @a))) + ((GHC.Classes.==) @(T14579.Wat 'Data.Proxy.Proxy)) (GHC.Classes./=) = GHC.Prim.coerce - @(T14579.Wat @a ('Data.Proxy.Proxy @a) - -> T14579.Wat @a ('Data.Proxy.Proxy @a) -> GHC.Types.Bool) + @(T14579.Wat 'Data.Proxy.Proxy + -> T14579.Wat 'Data.Proxy.Proxy -> GHC.Types.Bool) @(T14579.Glurp a -> T14579.Glurp a -> GHC.Types.Bool) - ((GHC.Classes./=) @(T14579.Wat @a ('Data.Proxy.Proxy @a))) + ((GHC.Classes./=) @(T14579.Wat 'Data.Proxy.Proxy)) instance forall a (x :: Data.Proxy.Proxy a). GHC.Classes.Eq a => GHC.Classes.Eq (T14579.Wat x) where (GHC.Classes.==) :: - T14579.Wat @a x -> T14579.Wat @a x -> GHC.Types.Bool + T14579.Wat x[sk:1] -> T14579.Wat x[sk:1] -> GHC.Types.Bool (GHC.Classes./=) :: - T14579.Wat @a x -> T14579.Wat @a x -> GHC.Types.Bool + T14579.Wat x[sk:1] -> T14579.Wat x[sk:1] -> GHC.Types.Bool (GHC.Classes.==) = GHC.Prim.coerce - @(GHC.Maybe.Maybe a -> GHC.Maybe.Maybe a -> GHC.Types.Bool) - @(T14579.Wat @a x -> T14579.Wat @a x -> GHC.Types.Bool) - ((GHC.Classes.==) @(GHC.Maybe.Maybe a)) + @(GHC.Maybe.Maybe a[sk:1] + -> GHC.Maybe.Maybe a[sk:1] -> GHC.Types.Bool) + @(T14579.Wat x[sk:1] -> T14579.Wat x[sk:1] -> GHC.Types.Bool) + ((GHC.Classes.==) @(GHC.Maybe.Maybe a[sk:1])) (GHC.Classes./=) = GHC.Prim.coerce - @(GHC.Maybe.Maybe a -> GHC.Maybe.Maybe a -> GHC.Types.Bool) - @(T14579.Wat @a x -> T14579.Wat @a x -> GHC.Types.Bool) - ((GHC.Classes./=) @(GHC.Maybe.Maybe a)) + @(GHC.Maybe.Maybe a[sk:1] + -> GHC.Maybe.Maybe a[sk:1] -> GHC.Types.Bool) + @(T14579.Wat x[sk:1] -> T14579.Wat x[sk:1] -> GHC.Types.Bool) + ((GHC.Classes./=) @(GHC.Maybe.Maybe a[sk:1])) Derived type family instances: diff --git a/testsuite/tests/deriving/should_fail/T15073.stderr b/testsuite/tests/deriving/should_fail/T15073.stderr index 129efe496d..f39fd19bbc 100644 --- a/testsuite/tests/deriving/should_fail/T15073.stderr +++ b/testsuite/tests/deriving/should_fail/T15073.stderr @@ -2,8 +2,7 @@ T15073.hs:8:12: error: • Illegal unboxed tuple type as function argument: (# Foo a #) Perhaps you intended to use UnboxedTuples - • In the type signature: - p :: Foo a -> Solo# @'GHC.Types.LiftedRep (Foo a) + • In the type signature: p :: Foo a -> (# Foo a #) When typechecking the code for ‘p’ in a derived instance for ‘P (Foo a)’: To see the code I am typechecking, use -ddump-deriv diff --git a/testsuite/tests/deriving/should_fail/deriving-via-fail5.stderr b/testsuite/tests/deriving/should_fail/deriving-via-fail5.stderr index a0a19ab65d..497e955896 100644 --- a/testsuite/tests/deriving/should_fail/deriving-via-fail5.stderr +++ b/testsuite/tests/deriving/should_fail/deriving-via-fail5.stderr @@ -59,12 +59,12 @@ deriving-via-fail5.hs:8:1: error: at deriving-via-fail5.hs:(8,1)-(9,24) • In the expression: GHC.Prim.coerce - @([] (Identity b) -> ShowS) @([] (Foo4 a) -> ShowS) + @([Identity b] -> ShowS) @([Foo4 a] -> ShowS) (showList @(Identity b)) In an equation for ‘showList’: showList = GHC.Prim.coerce - @([] (Identity b) -> ShowS) @([] (Foo4 a) -> ShowS) + @([Identity b] -> ShowS) @([Foo4 a] -> ShowS) (showList @(Identity b)) When typechecking the code for ‘showList’ in a derived instance for ‘Show (Foo4 a)’: |