Starlark error functions to return starlark::Error

Summary: Updating some error functions in starlark to return `starlark::Error` instead of `anyhow::Error`. Helps with removing some `from_any`

Reviewed By: JakobDegen

Differential Revision: D67865727

fbshipit-source-id: 274347a40fc7799efffa21bb1e93b495dcb40dec

starlark/src/values/layout/complex.rs

@@ -70,15 +70,14 @@ where
     }
 
     /// Downcast.
-    pub fn new_err(value: Value<'v>) -> anyhow::Result<Self> {
+    pub fn new_err(value: Value<'v>) -> crate::Result<Self> {
         match Self::new(value) {
             Some(v) => Ok(v),
             None => Err(value_error!(
                 "Expected value of type `{}`, got: `{}`",
                 T::TYPE,
                 value.to_string_for_type_error()
-            )
-            .into_anyhow()),
+            )),
         }
     }
 

starlark/src/values/layout/typed.rs

@@ -184,7 +184,7 @@ impl<'v, T: StarlarkValue<'v>> ValueTyped<'v, T> {
 
     /// Downcast.
     #[inline]
-    pub fn new_err(value: Value<'v>) -> anyhow::Result<ValueTyped<'v, T>> {
+    pub fn new_err(value: Value<'v>) -> crate::Result<ValueTyped<'v, T>> {
         value.downcast_ref_err::<T>()?;
         Ok(ValueTyped(value, marker::PhantomData))
     }
@@ -258,7 +258,7 @@ impl<'v, T: StarlarkValue<'v>> FrozenValueTyped<'v, T> {
 
     /// Downcast.
     #[inline]
-    pub fn new_err(value: FrozenValue) -> anyhow::Result<FrozenValueTyped<'v, T>> {
+    pub fn new_err(value: FrozenValue) -> crate::Result<FrozenValueTyped<'v, T>> {
         value.downcast_ref_err::<T>()?;
         Ok(FrozenValueTyped(value, marker::PhantomData))
     }

starlark/src/values/layout/value.rs

@@ -1342,14 +1342,13 @@ pub trait ValueLike<'v>:
 
     /// Get a reference to underlying data or [`Err`]
     /// if contained object has different type than requested.
-    fn downcast_ref_err<T: StarlarkValue<'v>>(self) -> anyhow::Result<&'v T> {
+    fn downcast_ref_err<T: StarlarkValue<'v>>(self) -> crate::Result<&'v T> {
         match self.downcast_ref() {
             Some(v) => Ok(v),
-            None => Err(ValueValueError::WrongType(
+            None => Err(crate::Error::new_value(ValueValueError::WrongType(
                 T::TYPE,
                 self.to_value().to_string_for_type_error(),
-            )
-            .into()),
+            ))),
         }
     }
 }

starlark/src/values/types/any_complex.rs

@@ -64,7 +64,7 @@ where
     }
 
     /// Obtain the value from a `Value`, if it is a `StarlarkAnyComplex<T>`.
-    pub fn get_err(value: Value<'v>) -> anyhow::Result<&'v T> {
+    pub fn get_err(value: Value<'v>) -> crate::Result<&'v T> {
         value.downcast_ref_err::<Self>().map(|x| &x.value)
     }
 }