Fix builds.

src/dynamic.rs

@@ -1,6 +1,6 @@
 //! Helper module which defines the [`Any`] trait to to allow dynamic value handling.
 
-use crate::fn_native::SendSync;
+use crate::fn_native::{shared_write_lock, SendSync};
 use crate::r#unsafe::{unsafe_cast_box, unsafe_try_cast};
 use crate::{FnPtr, ImmutableString, INT};
 #[cfg(feature = "no_std")]
@@ -283,14 +283,11 @@ enum DynamicWriteLockInner<'d, T: Clone> {
     /// A simple mutable reference to a non-shared value.
     Reference(&'d mut T),
 
-    /// A write guard to a shared [`RefCell`][std::cell::RefCell].
+    /// A write guard to a shared value.
+    ///
+    /// Not available under `no_closure`.
     #[cfg(not(feature = "no_closure"))]
-    #[cfg(not(feature = "sync"))]
-    Guard(std::cell::RefMut<'d, Dynamic>),
-    /// A write guard to a shared [`RwLock`][std::sync::RwLock].
-    #[cfg(not(feature = "no_closure"))]
-    #[cfg(feature = "sync")]
-    Guard(std::sync::RwLockWriteGuard<'d, Dynamic>),
+    Guard(crate::fn_native::LockGuard<'d, Dynamic>),
 }
 
 impl<'d, T: Any + Clone> Deref for DynamicWriteLock<'d, T> {
@@ -1593,10 +1590,7 @@ impl Dynamic {
         match self.0 {
             #[cfg(not(feature = "no_closure"))]
             Union::Shared(ref cell, _, _) => {
-                #[cfg(not(feature = "sync"))]
-                let value = cell.borrow_mut();
-                #[cfg(feature = "sync")]
-                let value = cell.write().unwrap();
+                let value = shared_write_lock(cell);
 
                 if (*value).type_id() != TypeId::of::<T>()
                     && TypeId::of::<Dynamic>() != TypeId::of::<T>()

src/engine.rs

@@ -5,16 +5,16 @@ use crate::custom_syntax::CustomSyntax;
 use crate::dynamic::{map_std_type_name, AccessMode, Union, Variant};
 use crate::fn_hash::get_hasher;
 use crate::fn_native::{
-    CallableFunction, IteratorFn, OnDebugCallback, OnParseTokenCallback, OnPrintCallback,
-    OnVarCallback,
+    shared_write_lock, CallableFunction, IteratorFn, Locked, OnDebugCallback, OnParseTokenCallback,
+    OnPrintCallback, OnVarCallback,
 };
 use crate::module::NamespaceRef;
 use crate::packages::{Package, StandardPackage};
 use crate::r#unsafe::unsafe_cast_var_name_to_lifetime;
 use crate::token::Token;
 use crate::{
-    Dynamic, EvalAltResult, Identifier, ImmutableString, Locked, Module, Position, RhaiResult,
-    Scope, Shared, StaticVec, INT,
+    Dynamic, EvalAltResult, Identifier, ImmutableString, Module, Position, RhaiResult, Scope,
+    Shared, StaticVec, INT,
 };
 #[cfg(feature = "no_std")]
 use std::prelude::v1::*;
@@ -205,12 +205,8 @@ impl Imports {
     pub(crate) fn global_constants_mut<'a>(
         &'a mut self,
     ) -> Option<impl DerefMut<Target = BTreeMap<Identifier, Dynamic>> + 'a> {
-        if let Some(ref mut global_constants) = self.global_constants {
-            #[cfg(not(feature = "sync"))]
-            return Some(global_constants.borrow_mut());
-
-            #[cfg(feature = "sync")]
-            return Some(global_constants.lock().unwrap());
+        if let Some(ref global_constants) = self.global_constants {
+            Some(shared_write_lock(global_constants))
         } else {
             None
         }
@@ -222,19 +218,12 @@ impl Imports {
             self.global_constants = Some(dict.into());
         }
 
-        #[cfg(not(feature = "sync"))]
-        self.global_constants
-            .as_mut()
-            .unwrap()
-            .borrow_mut()
-            .insert(name.into(), value);
-
-        #[cfg(feature = "sync")]
-        self.global_constants
-            .as_mut()
-            .lock()
-            .unwrap()
-            .insert(name.into(), value);
+        shared_write_lock(
+            self.global_constants
+                .as_mut()
+                .expect("`global_constants` is `Some`"),
+        )
+        .insert(name.into(), value);
     }
     /// Get the pre-calculated index getter hash.
     #[cfg(any(not(feature = "no_index"), not(feature = "no_object")))]

src/engine_api.rs

@@ -2211,8 +2211,6 @@ impl Engine {
             + SendSync
             + 'static,
     ) -> &mut Self {
-        use std::string::ParseError;
-
         self.token_mapper = Some(Box::new(callback));
         self
     }

src/fn_native.rs

@@ -39,6 +39,14 @@ pub use std::sync::Arc as Shared;
 #[cfg(not(feature = "no_closure"))]
 #[cfg(not(feature = "sync"))]
 pub use std::cell::RefCell as Locked;
+
+/// Lock guard for synchronized shared object.
+///
+/// Not available under `no_closure`.
+#[cfg(not(feature = "no_closure"))]
+#[cfg(not(feature = "sync"))]
+pub type LockGuard<'a, T> = std::cell::RefMut<'a, T>;
+
 /// Synchronized shared object.
 ///
 /// Not available under `no_closure`.
@@ -46,6 +54,13 @@ pub use std::cell::RefCell as Locked;
 #[cfg(feature = "sync")]
 pub use std::sync::RwLock as Locked;
 
+/// Lock guard for synchronized shared object.
+///
+/// Not available under `no_closure`.
+#[cfg(not(feature = "no_closure"))]
+#[cfg(feature = "sync")]
+pub type LockGuard<'a, T> = std::sync::RwLockWriteGuard<'a, T>;
+
 /// Context of a native Rust function call.
 #[derive(Debug)]
 pub struct NativeCallContext<'a> {
@@ -292,6 +307,16 @@ pub fn shared_take<T>(value: Shared<T>) -> T {
         .expect("no outstanding references")
 }
 
+#[inline(always)]
+#[must_use]
+pub fn shared_write_lock<'a, T>(value: &'a Locked<T>) -> LockGuard<'a, T> {
+    #[cfg(not(feature = "sync"))]
+    return value.borrow_mut();
+
+    #[cfg(feature = "sync")]
+    return value.write().unwrap();
+}
+
 /// A general function trail object.
 #[cfg(not(feature = "sync"))]
 pub type FnAny = dyn Fn(NativeCallContext, &mut FnCallArgs) -> RhaiResult;

src/module/resolvers/file.rs

@@ -1,4 +1,6 @@
+use crate::fn_native::shared_write_lock;
 use crate::{Engine, EvalAltResult, Identifier, Module, ModuleResolver, Position, Scope, Shared};
+
 #[cfg(feature = "no_std")]
 use std::prelude::v1::*;
 use std::{
@@ -202,19 +204,12 @@ impl FileModuleResolver {
 
         let file_path = self.get_file_path(path, source_path);
 
-        #[cfg(not(feature = "sync"))]
-        return self.cache.borrow_mut().contains_key(&file_path);
-        #[cfg(feature = "sync")]
-        return self.cache.write().unwrap().contains_key(&file_path);
+        shared_write_lock(&self.cache).contains_key(&file_path)
     }
     /// Empty the internal cache.
     #[inline]
     pub fn clear_cache(&mut self) -> &mut Self {
-        #[cfg(not(feature = "sync"))]
-        self.cache.borrow_mut().clear();
-        #[cfg(feature = "sync")]
-        self.cache.write().unwrap().clear();
-
+        shared_write_lock(&self.cache).clear();
         self
     }
     /// Remove the specified path from internal cache.
@@ -229,19 +224,9 @@ impl FileModuleResolver {
     ) -> Option<Shared<Module>> {
         let file_path = self.get_file_path(path, source_path);
 
-        #[cfg(not(feature = "sync"))]
-        return self
-            .cache
-            .borrow_mut()
+        shared_write_lock(&self.cache)
             .remove_entry(&file_path)
-            .map(|(_, v)| v);
-        #[cfg(feature = "sync")]
-        return self
-            .cache
-            .write()
-            .unwrap()
-            .remove_entry(&file_path)
-            .map(|(_, v)| v);
+            .map(|(_, v)| v)
     }
     /// Construct a full file path.
     #[must_use]
@@ -314,10 +299,7 @@ impl ModuleResolver for FileModuleResolver {
 
         // Put it into the cache
         if self.is_cache_enabled() {
-            #[cfg(not(feature = "sync"))]
-            self.cache.borrow_mut().insert(file_path, m.clone());
-            #[cfg(feature = "sync")]
-            self.cache.write().unwrap().insert(file_path, m.clone());
+            shared_write_lock(&self.cache).insert(file_path, m.clone());
         }
 
         Ok(m)