Add more closure tests.

src/parser.rs

@@ -1639,7 +1639,8 @@ fn parse_primary(
         // Function call
         Token::Identifier(s) if *next_token == Token::LeftParen || *next_token == Token::Bang => {
             // Once the identifier consumed we must enable next variables capturing
-            #[cfg(not(feature = "no_closure"))] {
+            #[cfg(not(feature = "no_closure"))]
+            {
                 state.allow_capture = true;
             }
             Expr::Variable(Box::new(((s, settings.pos), None, 0, None)))

tests/closures.rs

@@ -89,6 +89,36 @@ fn test_closures() -> Result<(), Box<EvalAltResult>> {
         42
     );
 
+    assert_eq!(
+        engine.eval::<INT>(
+            r#"
+                let a = 40;
+                let f = |x| {
+                    let f = |x| {
+                        let f = |x| plus_one(a) + x;
+                        f.call(x)
+                    };
+                    f.call(x)
+                };
+                f.call(1)
+            "#
+        )?,
+        42
+    );
+
+    assert_eq!(
+        engine.eval::<INT>(
+            r#"
+                let a = 21;
+                let f = |x| a += x;
+                f.call(a);
+                a
+            "#
+        )?,
+        42
+    );
+
+    #[allow(deprecated)]
     engine.register_raw_fn(
         "custom_call",
         &[TypeId::of::<INT>(), TypeId::of::<FnPtr>()],