Re-index imported modules if they are not yet indexed.

RELEASES.md

@@ -4,6 +4,14 @@ Rhai Release Notes
 Version 0.19.5
 ==============
 
+This version fixes a bug that prevents compilation with the `internals` feature.
+It also speeds up importing modules.
+
+Bug fixes
+---------
+
+* Fixes compilation error when using the `internals` feature.  Bug introduced in `0.19.4`.
+
 Breaking changes
 ----------------
 

doc/src/rust/modules/imp-resolver.md

@@ -15,6 +15,10 @@ of the _module path_ (i.e. the path specified in the [`import`] statement).
 
 * Upon success, it should return an [`Rc<Module>`][module] (or `Arc<Module>` under [`sync`]).
   
+  The module should call `Module::build_index` on the target module before returning.
+  This method flattens the entire module tree and _indexes_ it for fast function name resolution.
+  If the module is already indexed, calling this method has no effect.
+
 * If the path does not resolve to a valid module, return `EvalAltResult::ErrorModuleNotFound`.
 
 * If the module failed to load, return `EvalAltResult::ErrorInModule`.
@@ -40,12 +44,14 @@ impl ModuleResolver for MyModuleResolver {
     ) -> Result<Rc<Module>, Box<EvalAltResult>> {
         // Check module path.
         if is_valid_module_path(path) {
-            load_secret_module(path)    // load the custom module
+            let mut my_module =
-                .map(Rc::new)           // share it
+                load_secret_module(path)        // load the custom module
-                .map_err(|err|
+                    .map_err(|err|
-                    // Return EvalAltResult::ErrorInModule upon loading error
+                        // Return EvalAltResult::ErrorInModule upon loading error
-                    EvalAltResult::ErrorInModule(err.to_string(), pos).into()
+                        EvalAltResult::ErrorInModule(path.into(), Box::new(err), pos).into()
-                )
+                    )?;
+            my_module.build_index();  // index it
+            Rc::new(my_module)                  // make it shared
         } else {
             // Return EvalAltResult::ErrorModuleNotFound if the path is invalid
             Err(EvalAltResult::ErrorModuleNotFound(path.into(), pos).into())

src/engine.rs

@@ -3,7 +3,7 @@
 use crate::ast::{BinaryExpr, Expr, FnCallInfo, Ident, IdentX, ReturnType, Stmt};
 use crate::dynamic::{map_std_type_name, Dynamic, Union, Variant};
 use crate::fn_call::run_builtin_op_assignment;
-use crate::fn_native::{Callback, FnPtr, OnVarCallback, Shared};
+use crate::fn_native::{shared_try_take, Callback, FnPtr, OnVarCallback, Shared};
 use crate::module::{Module, ModuleRef};
 use crate::optimize::OptimizationLevel;
 use crate::packages::{Package, PackagesCollection, StandardPackage};
@@ -2132,7 +2132,15 @@ impl Engine {
                         let module = resolver.resolve(self, &path, expr.position())?;
 
                         if let Some(name_def) = alias {
-                            mods.push(name_def.name.clone(), module);
+                            if !module.is_indexed() {
+                                // Index the module (making a clone copy if necessary) if it is not indexed
+                                let mut module =
+                                    shared_try_take(module).unwrap_or_else(|m| m.as_ref().clone());
+                                module.build_index();
+                                mods.push(name_def.name.clone(), module);
+                            } else {
+                                mods.push(name_def.name.clone(), module);
+                            }
                         }
 
                         state.modules += 1;

src/module/mod.rs

@@ -60,23 +60,17 @@ pub struct FuncInfo {
 pub struct Module {
     /// Sub-modules.
     modules: HashMap<String, Module>,
-
     /// Module variables.
     variables: HashMap<String, Dynamic>,
-
     /// Flattened collection of all module variables, including those in sub-modules.
     all_variables: HashMap<u64, Dynamic, StraightHasherBuilder>,
-
     /// External Rust functions.
     functions: HashMap<u64, FuncInfo, StraightHasherBuilder>,
-
     /// Iterator functions, keyed by the type producing the iterator.
     type_iterators: HashMap<TypeId, IteratorFn>,
-
     /// Flattened collection of all external Rust functions, native or scripted,
     /// including those in sub-modules.
     all_functions: HashMap<u64, CallableFunction, StraightHasherBuilder>,
-
     /// Is the module indexed?
     indexed: bool,
 }
@@ -181,6 +175,23 @@ impl Module {
             && self.type_iterators.is_empty()
     }
 
+    /// Is the module indexed?
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use rhai::Module;
+    ///
+    /// let mut module = Module::new();
+    /// assert!(!module.is_indexed());
+    ///
+    /// module.build_index();
+    /// assert!(module.is_indexed());
+    /// ```
+    pub fn is_indexed(&self) -> bool {
+        self.indexed
+    }
+
     /// Clone the module, optionally skipping the index.
     #[inline(always)]
     fn do_clone(&self, clone_index: bool) -> Self {
@@ -1120,7 +1131,7 @@ impl Module {
     /// Name and Position in `EvalAltResult` are None and must be set afterwards.
     ///
     /// The `u64` hash is calculated by the function `crate::calc_native_fn_hash` and must match
-    /// the hash calculated by `index_all_sub_modules`.
+    /// the hash calculated by `build_index`.
     #[inline(always)]
     pub(crate) fn get_qualified_fn(&self, hash_qualified_fn: u64) -> Option<&CallableFunction> {
         self.all_functions.get(&hash_qualified_fn)
@@ -1396,10 +1407,12 @@ impl Module {
         Ok(module)
     }
 
-    /// Scan through all the sub-modules in the module build an index of all
+    /// Scan through all the sub-modules in the module and build a hash index of all
-    /// variables and external Rust functions via hashing.
+    /// variables and functions as one flattened namespace.
+    ///
+    /// If the module is already indexed, this method has no effect.
     #[cfg(not(feature = "no_module"))]
-    pub(crate) fn index_all_sub_modules(&mut self) {
+    pub fn build_index(&mut self) {
         // Collect a particular module.
         fn index_module<'a>(
             module: &'a Module,

src/module/resolvers/file.rs

@@ -155,7 +155,7 @@ impl ModuleResolver for FileModuleResolver {
                     Box::new(EvalAltResult::ErrorInModule(path.to_string(), err, pos))
                 })?;
 
-                m.index_all_sub_modules();
+                m.build_index();
 
                 let m: Shared<Module> = m.into();
                 module = Some(m.clone());

src/module/resolvers/stat.rs

@@ -50,7 +50,7 @@ impl StaticModuleResolver {
     /// Add a module keyed by its path.
     #[inline(always)]
     pub fn insert(&mut self, path: impl Into<String>, mut module: Module) {
-        module.index_all_sub_modules();
+        module.build_index();
         self.0.insert(path.into(), module.into());
     }
     /// Remove a module given its path.