Fix bug on chaining function calls returning shared values.

CHANGELOG.md

@@ -12,6 +12,7 @@ Bug fixes
 * Parsing of index expressions is relaxed and many cases no longer result in an index-type error to allow for custom indexers.
 * Merging or combining a self-contained `AST` into another `AST` now works properly.
 * Plugin modules/functions no longer generate errors under `#![deny(missing_docs)]`.
+* Calling a property on a function call that returns a shared value no longer causes an error.
 
 Deprecated API's
 ----------------

src/eval/chaining.rs

@@ -652,7 +652,9 @@ impl Engine {
             _ if is_assignment => unreachable!("cannot assign to an expression"),
             // {expr}.??? or {expr}[???]
             expr => {
-                let value = self.eval_expr(scope, global, caches, lib, this_ptr, expr, level)?;
+                let value = self
+                    .eval_expr(scope, global, caches, lib, this_ptr, expr, level)?
+                    .flatten();
                 let obj_ptr = &mut value.into();
                 let root = ("", expr.start_position());
                 self.eval_dot_index_chain_helper(
@@ -1043,6 +1045,11 @@ impl Engine {
                 })
             }
 
+            #[cfg(not(feature = "no_closure"))]
+            Dynamic(Union::Shared(..)) => {
+                unreachable!("`get_indexed_mut` cannot handle shared values")
+            }
+
             _ if use_indexers => self
                 .call_indexer_get(global, caches, lib, target, &mut idx, level)
                 .map(Into::into),

tests/closures.rs

@@ -1,5 +1,5 @@
 #![cfg(not(feature = "no_function"))]
-use rhai::{Engine, EvalAltResult, FnPtr, ParseErrorType, Scope, INT};
+use rhai::{Dynamic, Engine, EvalAltResult, FnPtr, ParseErrorType, Scope, INT};
 use std::any::TypeId;
 use std::cell::RefCell;
 use std::mem::take;
@@ -217,6 +217,34 @@ fn test_closures_sharing() -> Result<(), Box<EvalAltResult>> {
         6
     );
 
+    #[cfg(not(feature = "no_object"))]
+    {
+        let mut m = Map::new();
+        m.insert("hello".into(), "world".into());
+        let m = Dynamic::from(m).into_shared();
+
+        engine.register_fn("baz", move || m.clone());
+
+        assert!(!engine.eval::<bool>(
+            "
+                let m = baz();
+                m.is_shared()
+            "
+        )?);
+
+        assert_eq!(
+            engine.eval::<String>(
+                "
+                let m = baz();
+                m.hello
+            "
+            )?,
+            "world"
+        );
+
+        assert_eq!(engine.eval::<String>("baz().hello")?, "world");
+    }
+
     Ok(())
 }